Proceedings of 4th edition Symposium on Space Educational Activities : April 27th, 28th, 29th 2022, Barcelona, Spain : inspiring through space

April 27th, 28th, 29th 2 022 Barcelona, Spain S Y M P O S I U M O N S P A C E E D U C A T I O N A L A C T I V I T I E S 4th Edition P R O C E E D I N G S O F Inspiring through space First edition : julio de 2022 © The Authors , 2022 © Iniciativa Digital Politècnica, 2022 Oficina de Publicacions Acadèmiques Digitals de la UPC Jordi Girona 31, Edifici Torre Girona, Plant 1, 08034 Barcelona Tel.: 934 015 885 www.upc.edu/idp E-mail: [email protected] ISBN: 978-84-19184-40-5 Any form of reproduction, distribution, public communication or transformation of these works, beyond activities that are directly authorised by law, require the permission of the owners The Editors : Miquel Sureda Anfres Daniel Garcia-Almiñana Gisela Detrell Alberto Garc i a-Rigo Ramón M. García Alarcia Guillem Megías Homar David González Díez 4 th Symposium on Space Educ ationa l Acti viti es Barcelon a, Apr il 2 022 III Preface The 4th Symposium on Space Educati onal Activit ies (4 th SSEA) was hosted at t he Universi tat Politècni ca de Catalunya (UPC) · Barcel onaTech in Barcelon a, Spain, from 27th – 29th April 2022. It was co - organized by the European Space Agency (ESA) and the UPC. The event represented the 4 th editio n of a successful Space Edu cation symposi um that bega n at the Uni versity o f Padova, It aly, in 2015, followed by the 2 nd Symposium hosted by the Budapest University of Technology and Economi cs, Hungary, i n 2018, a nd the 3 rd Symposium host ed by the Universit y of Lei cester, UK , i n 2019. This long - awaited edition exceeded al l expectations and gathered more t han 500 attendees i n Barcelona. The 4 th SSEA Organiz ing Committee develope d a comp elli ng outreach campaign that reached to more than 2000 departments and universities. It ra ised support from more than 10 private companies, and it had wide support f rom the local, regional and country - level institution s. During the three days of the event in UPC’s venue Edifici V èrtex, the attendees engaged in fruitful research discussions, established connections among the European sect or and learned from the lat est projects in space educatio n and student - led projects. The transformati on of the space secto r, as a result of new tech nology, busine ss and policy trend s, creates new chal lenges for the education system, which must adapt to new secto r needs . NewSpace, artificial intell igence, machine learning, additive manufactur ing … A ll these advance s create new needs for a more interdisciplinary education. This i s the real meani ng of an event like the Symposium on Space Educational Activi ties . Here we pre sent the symposium procee dings that summarize all the presentations held during t he event. We al so i ntrod uce a summ ary of t he sy mposi um or ganiz ati on, e vents and awar ds. 4 th Symposium on Space Educ ationa l Acti viti es Barcelon a, Apr il 2 022 IV 4 th SSEA22 group pict ure Keynote Speaker Jordi Puig Suari at the Venue Gala Di nner a t the Fabra Observat ory 4 th Symposium on Space Educ ationa l Acti viti es Barcelon a, Apr il 2 022 V Organizi ng Inst ituti ons The 4 th Symposium on Space Educat ional Acti vities ( SSEA) was organised by the European Space Agency (ESA), through the ESA Academy programme of the ESA Educati on Office ; a nd the Universita t Politècni ca de Catal unya · Bar celonaTech ( UPC). It was organised in partn ership with the IEEC, ICCUB and i2cat research centres, as wel l as with the institutional sponsorship of the Generalitat de Catalunya. The ESA Academy, part of the ESA Educatio n Office , is ESA's over archi ng programme for Universi ty student s from ESA member stat es, Canada, Latvi a, Lithuani a, and Sloveni a . The ESA Academy provide s students wi th access to both Hands - on Projects and a Training and Learning Programme, as well as supporting, through organisation and funding, the Symposium on Spa ce Educatio nal Activ ities. The Universitat Politècnica de Catalunya · BarcelonaTech (UPC) is a public inst ituti on of research and higher education in the fields of engineering, architecture, sciences and technology, and one of the leading technical universities in Europe. UPC’s schools devoted to research and education on the aerospace field are: ESEIAAT , EETAC , and ETSETB . 4 th Symposium on Space Educ ationa l Acti viti es Barcelon a, Apr il 2 022 VII Organizing C ommittee The 4 th SSEA was a realit y thanks to the wo rk of a diver se team of committ ed and hard - work ing members. Fo llowi ng the mott o of “a Sympos iu m made fo r student s – by students”, t he Organisi ng Team was balanced mi x of professors and students and incl uded member s from different backgrounds and institution s . The core Organisi ng Committee was com posed by: • Dr. Miquel Sureda Anfres ( UPC · Barc elonaTech ) – General Chair • Mr. Ramón M. García Alarcia (ISAE – SUPAERO ) – Vice -ch air • Mr. Guille m Megías Homar ( Stanford University ) – Vice -c hair • Dr. David González Díez ( UPC · BarcelonaTech ) – Vice -c hair • Dr. Daniel Garcia Almiñana ( UPC · BarcelonaTech ) – Vice -c hair • Dr. Gisela Detrell ( University of Stuttgart ) – Co -c hair of technical a nd educational activities • Ms. Magda Escorsa ( UPC · BarcelonaTech ) – Co -c hair of technical a nd educational activities • Dr. Anna Ferré -M ateu ( Instituto de Astrofísica de Canarias ) – Co -c hair of technical and educational activities • Dr. Alberto Garc i a -R igo ( Institut d’Estudis Espacials de Catalunya ) – Co -c hair of technical and educational activities • Mr. Alexander Kinnaird ( ESA Academy ) – Co -c hair of technical a nd educational activities • Ms . Laia L ópez ( International Space University ) – Co -c hair of technical a nd educational activities • Ms. Anna Ruiz Ayala ( INECO ) – Co -c hair of tec hnical and educational activities • Dr. Núria Salán ( UPC · BarcelonaTech ) – Chair of Gender equality, Diversity and Sustainability Board • Dr. Adriano Camps ( UPC · BarcelonaTech ) – Chair of Scientific and Technical Activities Board • Ms. Carme Fenoll ( UPC · BarcelonaTech ) – Chair of Logistics Board For better preparati on and organ isation o f the eve nt, the Organising Commit tee creat ed and supervised several autonomous boards tackl ing diff erent aspects such as communications ; logistics ; scientific and techni cal activities; sponsors ; sustainability , equity and diversi ty; etc. The Communicatio ns Board , in charge of social med ia, newsletter s , and the even t’s commun ications and image in gener al , was composed of: 4 th Symposium on Space Educ ationa l Acti viti es Barcelon a, Apr il 2 022 VIII • Ms. Laia López Llobet, Chair • Ms. Àurea Cors • Ms. Blan ca Pavón • Ms. Lídia Fuentes • Ms. Mar ina Can te • Mr. José Ángel Gómez • Ms. Gemma Domènech • Mr. Arna u Amorós The Logisti cs Board , in charge of the event logistics and suppliers , timetable , and social events, was composed of: • Ms. Anna Ruiz Ayala, Chair • Mr. Ju an Fran cisco Lopera Zafra • Mr. Dan iel S ors • Ms. Lau ra Gonz ález • Mr. Ser gio T abasco • Ms. Núr ia Esc ursel l • Ms. Ari adna A nguita The Scienti fic and Technical Board , in charge of the Call for Abstracts, paper select ion, an d preparation of Proceedi ngs, was composed of: • Prof. Adr iano Camps ( UPC · Barcel onaTech ), Chair • Dr. Daniel Garcia Almiñana ( UPC · Bar celonaTech ) , Executive Cha ir • Dr. Gisel a Detrel l ( Uni versity of Stut tgart ) • Dr. Sil via Rodri guez - Donaire ( UPC · Ba rcelonaTech ) • Dr. Joan Montaña Puig ( UPC · BarcelonaTe ch ) • Dr. Manel Soria ( UPC · BarcelonaTe ch ) • Dr. Pil ar Gil Pons ( UPC · Barcelon aTech ) • Dr. Jordi Gutiér rez Cabell o ( UPC · Barcelon aTech ) • Mr. Pi ero Ga leone (E SA Re tiree, form er Head of ESA Academy ) • Dr. Nigel P. Banni ster ( Universi ty of L eicester ) • Dr. Laszl o Bacsardi ( Budapest Universi ty of Te chnology and Economics ) • Dr. Lorenz o Olivi eri ( Center of Studies a nd Activi ties f or Space “ G. Colombo” ) • Dr. Alber to Garci a - Rigo ( Institut d’Estudis Espacials d e Catalunya ) • Dr. Anna Fe rré - Mateu ( Instituto de Astrofísica d e Canarias ) • Ms. Lai a Lópe z ( International Space Unive rsity ) • Dr. Georg Herdrich ( Univer sity of Stuttgar t ) 4 th Symposium on Space Educ ationa l Acti viti es Barcelon a, Apr il 2 022 IX • Ms. Mar iona Ba denas Ag ustí ( Mass achus etts Institute of Technology ) • Dr. Maria de Soria ( Jet Propulsion Laboratory ) • Ms. Beat riz Jilet e ( GMV ) • Ms. Arme lle Frenea - Schmi dt ( Swedis h Space Corpor ation ) • Mr. Bor ja Lá zaro To rall es ( Ma nufact uring Technol ogy Ce nter ) • Mr. Jo nathan Becedas ( Elecno r Deimos ) • Mr. Jo rdi Es cofet Miró ( INS Terrassa ) • Mr. Domi ngo Es cutia Muñoz ( ESERO Spain ) • Dr. Ed Ches ter ( Goonhil ly Ear th Sta tion Ltd ) • Dr. Nicol as Nolhi er ( Uni versity Paul Sabat ier of Toulouse ) • Ms. Cl ara Cr uz Nigg ebrugge ( ESA Aca demy ) • Mr. Jo sep Vi rgili Llop ( Space X ) • Mr. Al exander Kinnai rd ( ESA Academy ) • Ms. Ari an e Dedeban ( ESA Ac ademy ) The Sustaina bility, Equity and Div ersity Board , in charge of ensuring the meeting of the event’s social goals and assigning schol arships, was compo sed of: • Dr. Núri a Salán, Cha ir • Dr. Anna Fe rré - Mateu The Sponsor s Boar d , in charge of secur ing fundi ng through sponsors, taking care of their needs, and maintai ning exter nal relations, was composed of: • Mr. Gui llem Megias Homar, Chair • Dr. David González • Ms. Magd a Escor sa 4 th Symposium on Space Educ ationa l Acti viti es Barcelon a, Apr il 2 022 XVII Awards 1 - Best Oral Pr esentation Title: Dev elopment of a Low - Cost Ground Segment Capable o f Receivi ng Data f rom Nanosate llites : a Partnershi p between Br azil and Portugal Authors: J úlio Sant os, Jeremy Silva, J oí£o Braga, André Tei xeira, Mar cos Kakit ani and Hen rique Alves 2 - Highly Commended Oral Presentat ion 1 Title: The effect of previou s spacefli ght on ot olith - mediate d ocul ar cou nter - roll in cosmon auts after long dur ation spa ceflight Authors: Ca tho Schoenmaeker s, Flori s Wuyts and Steven Ji llings 3 - Highly Commended Oral Present ation 2 Title: ASCen SIon Innovat ive Trai ning Networ k: mid - term overview and les sons learned Authors: Al essia Gl oder, Mart in Tajmar and Chris tian Bach 4 - Best Poster Title: Ana lysis of Impulsiv e and Low - Thrust Transfer Orbits for ESA's LIS A Mis sion under Third - Body Perturbati ons Authors: J uan Palomares , Oriol Lizandre and Blanca Tejedor 5 - Highly Commended Poster Title: An Augmented Real ity App teaches vol cano monito ring fr om Space in Schools wi th Sentin el - 1 data Authors: Cl audia Li nd ner, Christi an Nadolsky, Carsten Juergens, Karl - Heinz Ott o and Andrea s Rienow 4 th Symposium on Space Educ ationa l Acti viti es Barcelon a, Apr il 2 022 XIX Table of Cont ents PAPERS Antoni Per ez - Poch et. al .: Challenge - Based Learning and the Ba rcelona Zer oG Challeng e: A Space Educat ion Case St udy .............................................................................................................. 3 Alba Badia Rifà et . al.: Final test ing, pre - launch activities , launch and pos t - launch a nalysis o f a soun ding rock et mad e by students in Spain ................................................................................................................................... 9 Davide Bel licoso: A student perspective into ESA Academy Space Systems Engi neering Training Course ................... 15 Elke D'Huys et. al .: Come fly wi th us: services provide d by the Space Weather EducationCe ntre ..................................... 18 Guill em Oliv ella, Marcel Mari n: Design and implemen tation o f space e ducation al activities to mot ivate you ng stud ents in C atalonia . 23 Iván Serma noukian Mo lina et. al.: Missio n anal ysis of nan osatel lite const ellat ions with Op enSatKi t ......................................................... 28 Josep Sit jar Suñer e t. al.: Design and methodology for a Remot e Sensing course ...................................................................... 34 David Herna ndo - Diaz: CANSAT Competiti on 2020: Best techn ical dev elopment by OrbiSat team ........................................ 38 Knight Tri stan et. al.: TOLOSAT project: Gravimet ry and Communic ation ............................................................................ 43 Adrià Rovi ra - Garcia et. al.: gLAB hands - on education on satell ite navigation ................................................................................ 48 Teresa Peña: Analysis o f planet ary spacecra ft images with SPICE .......................................................................... 54 Melina Koukou et. al.: SDR Helix An tenna Deplo yment Experi ment (SHADE) o n board BEXUS .......................................... 60 Hugues Sana, Clio Gie len: The advanced Mast er of Spa ce Studies at KU Leuven and Ghent Uni versity: Trends and t endencies i n the prog ram demographics ......................................................................... 66 Jordi Grau Rifà, ESEIAAT UPCSP Spain: Design and optimizat ion of a rocket structu re foll owing the requiremen ts for the European Rocketry Challenge (EUROC) to be fabrica ted using additi ve manufact uring .................................................... 72 Pablo Salga do Sánchez: The “Effect of Marangon i convecti on on heat transfer in Phase Cha nge Material s” experiment , from a student project to the International Space Station ............................................................................... 78 4 th Symposium on Space Educ ationa l Acti viti es Barcelon a, Apr il 2 022 XX Mark Wyl ie, Leonardo Bari laro: An investi gation i nto cold weld adhes ion fo r spacecraft repair after a space debris impact u sing space education based sub - orbital sounding rocket plat form ........................................................................ 84 Georgie Crewdso n et. al. : Supporting an ISS expe riment as PhD students : a case study of the PARTICLE VIBRATION pr oject ........................................................................................................... 90 Dr. Paul ILIFFE: The Sat - Comms Game: t eaching a complex sub ject fo r inter discipl inary au diences . ......................... 96 C. J alba et. al. : DEAR project : Lunar Dust Surfac e inter actions, Risk and Removal i nvestigat ions ........................... 101 Rosa Olive lla et. al.: Monitor ing n atural phenome na fro m the classr oom wit h Edus at. Pr oposal for a teac hing g uide ( and support materi al) ................................................................................................................................ 107 Radu - Andrei Ci oaca et. al.: Testing campai gn for ECRIDA: the UV res in 3D prin ter flyi ng on REXUS ......................................... 113 Will iam C roft s et . al .: Developing a 3U CubeSat Engineeri ng Model - FlatSat & Chassis Desi gn ....................................... 118 Sara Dall edonne et. al.: Space Educati on in Eur ope: Statu s and Prospe cts) .......................................................................... 124 Joseph Mangan et. al.: Experiences in Firmwar e Development for a CubeSat Inst rument Payl oad ...................................... 130 Federico Di Giacomo, Maura Sandri : Educational activi ties wit h Arduino to lear n about a stronomy ............................................................ 136 Angel Porr as - Hermoso et. al .: Design and calibra tion proc ess of s olar sen sors for small s atelli te missi ons ................................ ..... 141 Stefan Lobas et. al .: Cosmic Call Tech – A hands - on space radio workshop for st udents in secondary educati on ............ 147 Jack Reilly et. al. : EIRFLAT - 1: A FlatSat pl atform for the deve lopment and testing of the 2 U CubeSat EIRSAT -1 ........... 152 Jennifer Hoffmann et. al. : Development of a Concur rent Engi neering T ut orial as part of t he “ESA_Lab@” initiative ...................... 158 Anita Alf ano et. al.: Spazio all o Spazio ............................................................................................................................. 164 Marcel Stefk o et. al.: SAR - An Augmented - Realit y App for Explorat ion of Principl es of Sy nthetic Aperture Ra dar ............. 170 Úrsula Mar tínez et . al.: ATTITUDE CONTROL RESEARCH WITH EDUCATI ONAL NANOSATELLITES ............................ 174 Ernest Tort osa et. al.: Progress of the Devel opment of a Two - Sta ge Supersonic Rocket within a Student’s Associati on ......................................................................................................................... 180 Marcel Liegi bel et . al .: Meteor observ ation with the SOURCE CubeSat – Develop ing a si mulation to test on - board meteor detection algori thms ........................................................................................................................... 186 4 th Symposium on Space Educ ationa l Acti viti es Barcelon a, Apr il 2 022 XXI Daniel Sch loms et. al.: A Flexibl e CubeSat Edu cation Pl atform Combi ning Soft ware Develo pment and Har dware Engineerin g ........................................................................................................................................ 192 Javier Cubas et. al.: An example of Space Engi neering Edu cation i n Spain: a master i n space bas ed on Proj ect - Based Learning (PBL) ................................................................................................................................... 198 Özlem Baş man Bari laro, Dr Ma rio C ardona Potential applica tion of a measurement tool f or quali ty assuranc e of E - Learning conten t to a new MSc in Aerospa ce Engi neeri ng ................................ .......................................................................... 204 Elena Álvar ez Castro et. al.: Moon Rove r Chal lenge. An edu catio nal sp ace ro botics reso urce t o teac h prog ramming and pr omote space careers at secondary educati on levels .................................................................................... 210 Johanna Mehringer et. al.: Suborbital Autorot ation Landi ng Demonstr ator on REXUS 29 .......................................................... 216 Juan Bermejo - Ballesteros et. al.: Mubody, an ast rodynami cs op en - source Python libr ary focused on librati on points .......................... 222 Adrián Mart ínez et. al .: Further evi dence of t he long - term thermosph eric density varia tion using 1U C ubeSats ................... 228 Michael Halv orson et. al.: A Model - Based Syst ems Engineeri ng Approach to Space Mi ssion Educa tion of a Geographi cally Disperse Student Work force .............................................................................................................. 234 Jonas Jelonek et. al.: BEXUS30 – ELFI: Measuri ng Schumann r esonances in the atmosp here ......................................... 24 0 Marcela Salaz ar et. al .: Hypergravi ty induc es changes in physi ology, gene expres sion and e pigenetic s in ze brafish ........... 246 C.C. Lin et. al. : Challenge of teachi ng complex, end - to - end space system design and development process: Eart h Observat ion Sa telli te Sys tem Desi gn tr ainin g cour se ........................................................................ 252 Clémence Duboi s et. al .: Blended - Learning Educati onal Concept for Eart h Observation at Univer sity Leve l ........................... 258 Kevin Waizene gger et. al .: Development and Testi ng of the 3U+ Cube Sat PCDU for SOURCE ................................................ 264 V. Eschelmül ler et. al .: Development of a CubeSat CLIMBing t o the Van - Allen belt .............................................................. 270 Maximil ian v on Arni m et. al.: Improved S ensor Fusion for Flying Lapto p Based on a Multiplicative E KF ........................................ 276 Anton Atanaso v, Viktor Danchev: Space Communicat ion System for Educati on .................................................................................... 282 Joost Vanreusel et. al. : ESA Academy’s Or bit Your Thesis! Pr ogramme ............................................................................... 288 Maeve Doy le et. al .: Update on t he status of the Educational Iris h Research Satelli te (EIRSAT - 1) .................................. 294 4 th Symposium on Space Educ ationa l Acti viti es Barcelon a, Apr il 2 022 XXII Chantal Capp elletti et. al.: Establishi ng Thriv ing Univer sity - Level Space Educati on ................................ ................................... 300 Natacha Cal lens et. al .: The Student Aerospace Chal lenge: a Eu ropean multi discipli nary contest and tert iary educa tional programme ......................................................................................................................................... 306 A. Camps: UPC NanoSat - Lab - Past, Present and Future Act iviti es ................................................................... 312 Alejandro García et . al.: Deployable Fresn el Zone Plate a ntenna for CubeSat s ............................................................. 318 Lana Laskey : Space Games: Evalu ating Game - Based Vi rtual Reality in Higher Education .................................... 324 Dr. Sara Langston : Space Educati on: Chall enges and St rategies in Teachi ng Space Pol icy to Techni cal Univers ity Students ............................................................................................................................................. 330 Arias Hel ena et. al.: Hypatia I : a mult i - generational and multi - disciplinar y crew of female analog astr onauts dedicated to space research, scientific outreach, and promotion of female rol e models in space careers ............ 336 Alexis Leo n Delgado et . al.: A multi - project student space associati on .......................................................................................... 342 Ota Mic halek et. al.: Findings f rom the ESA Edu cation Fly a Rocket Campai gn – Sensor Experiments Te am .................. 3 48 Tony Erdmann, Mar a Krachten: Lessons - learned from Te aching Satellite O perations in a No vel Hands - on Student Project Utilizing In - Orbit Sp acecraf t Duri ng th e COVID - 19 Pandemic ......................................................................... 354 Alexander Ki nnaird et. al .: A selecti on of l essons lear ned from ph ase C/D of CubeSat pro jects of the Fly Your Satellit e! Programme ........................................................................................................................................ 360 Markus Grass et . al.: The Space Stat ion Design Wo rksho p goe s di git al - opport unities and chall enges during pandemic - times ................................................................................................................................................... 366 Frenea - Schmidt Ar melle et. al.: From education al programmes t o professi onal proj ects: fi nding fl ight opportunities ......................... 372 Alexander Ki nnaird et. al.: ESA Academy Acti vities during COVID - 19 ........................................................................................ 378 Claudia Guer ra et. al.: Fly a Rocket ! ESA's hands - on programme for undergraduate st udents ............................................ 384 Laszlo Bacsardi, Laszlo Csurgai - Horvath: Establishmen t of th e Spa ce Engineering Program in Hungary .......................................................... 390 Sahba El - Shawa et. al.: JSRI Space Design Competitions: Education and Outreach for Emerging Space Countries ............ 395 Rovin Perez , Slavey a Abadzhieva : Design Chal lenges, a nd Outcomes o f Building a Satelli te t he Size o f a Soda Can ........................... 401 4 th Symposium on Space Educ ationa l Acti viti es Barcelon a, Apr il 2 022 XXIII Apoorva Joshi et. al.: AMORE - Mission concep t over view for a progr essive ly i ndepende nt and self - sustainable lunar hábitat ....................................................................................................................................... 407 Lara Fernandez Dep loyment m echanism for an L - Band Helix an tenna on - board the 3Cat -4 1U CubeSat ................. 413 Lorenzo Frezza et. al. : Lessons learned during t he development of LEDSAT from the students of the S5Lab ..................... 418 Fe derico Toson et. al.: O- ZONE: affordable strat ospheric air dynamic sampling device ....................................................... 424 Katarzyna Mal inowska, Michał Szwaj ewski : The role of the key educational paths f or ESA new member states as a risk re duction i ndex for the newcom ers. .................................................................................................................................. 430 Maur a Zara, Si fat Kaur Alag : What T hey Want a nd Wha t Th ey Ne ed: T he Ne w Rol e of the Juri st in As sis ting the Young Spac e Companies ................................................................................................ ......................................... 436 A. Perez - Portero et. al.: RITA: A 1U multi - sensor Earth observation payload for t he AlainSa t-1 ............................................. 442 Charles Mwang i, Malki a Kelelu e : Implementa tion of Space C l ubs in Kenya ................................................................ .......................... 446 Joseph Thompson et. al.: Thermal Charact erization Testing of a Robust and Reliabl e Thermal Kni fe HDRM (Hold Down and Release Mec hanism) for CubeSat Deploy ables ................................................................................. 452 Gisela Detrel l et. al.: From Soyuz - docking manoeuvres to mi croalgae cultivat ion: hands - on training for Master's students ............................................................................................. 458 Alessandro Bortotto et. al.: ERMES: Design a nd preliminary simulat ions for an autono mous dock ing manoeu vre ..................... 464 Maria Alexand ra Nit a et. al.: A story ab out how th e novel ROSPIN Academy progr amme is bri nging space education to the Romanian yout h in th e pandemic c ontext ......................................................................................... .470 Francesco De Ceci o et. al.: TEASPOON: a once i n a lif etime opport unity to Sedna ..................................................................... 476 Federico Basan a et. al.: Development of a mult i - payload 2U CubeSat: t he Alba Project ........................................................ 482 Paolo Marzi oli et. al.: From BEXUS to HEMERA: T he appl ication of l essons learned on the devel opment and manufact uring of st ratos pheric payl oads at S5Lab ............................................................................ 488 Alondra Sol á Molina et. al.: Asociación Aeroespacial Cosmos: edu cational impact and returns of a three - year - old student aerospace association ....................................................................................................................... 494 Francesco Bian chi et. al. : Collaborat ive Space Design pr oject: A student’ s experi ence ............................................................ 500 Chien Lin Soh et. al.: Domi Inter Astra ( DIA) Moon Bas e: an i nterdisc iplinar y approach for c ooperation t o build a near - future Moonb ase and how to use it as an educational too l .................................................... 506 4 th Symposium on Space Educ ationa l Acti viti es Barcelon a, Apr il 2 022 XXIV Laia Casamiquela et. al .: Finestres a l cel .................................................................................................................................. .512 Léa Rouverand et. al.: Experiment collabora tion prog ram during a Marti an analogue mission to introduce youn g students to human sp ace exploratio n ............................................................................................................... 518 Arnau Torre nt et. al. : Student perspective and l essons learned from par ticipating i n the European Rover Chall enge 2021 ................................................................................................................................................... 524 M. Badi a et. al .: Montsec Ground Stati on .................................................................................................................... 529 Anastasios - Faid on Retselis et. al.: Adaptation of the AcubeSAT nanosatel lite project into re mote working during the COVID - 19 era ........... 533 Fernando Amador Pla et. al.: A multi - perspective comparison of ESA Academy’s Traini ng and Learni ng Programme experiences before and throughout COVID - 19 pandemic through the eyes of 6 students ............................................. 539 Luis Cormier et. al .: FlatSat Worksh ops Teaching F undamental Electronics Skil ls for CubeSat Buil ding ................................ . 545 Augustin Gal lois et. al.: Lotus: Testing Origami - Inspired Structures in Micro gravity ............................................................... 551 Luis García Mozos et. al .: Artery in Microgravity (AIM): Assembly, Integration, and Testing fo r a Student Payload for the ISS ......... 5 5 7 Oriel Marshal l et. al .: Demonstrati ng Cosmologi cal and Doppler Reds hift i n the Cl assroom ........................................................ 563 Ana Gebejes et . al.: Six - year evolution of a space - inspired collab orative p roblem - so lving study program in Finl and ............... 569 Albert Mor ea et. al.: 3 Cat - 4 Mission, 1 - Unit CubeSat for Earth Observ ation: Evaluation on the q ualific ation and producti on during Phase D .................................................................. 575 Andy Chia et. al.: Development of a Pro of - of - Conc ept Space Propulsio n System fo r Nanosatel lite appl ications using Additive Manufacturi ng .................................................................................................................................. 581 Mario Andre Z uegner : Ice Moon R esearch – A phenomenon cal led plume ..................................................................................... 587 Hendrik Kuh m et. al.: Design and Development of the Re - Entry Sensor System for the CubeSat Mi ssion SOURCE ................ 593 Roger Macías et. al.: 3D printed telescopes: an interesting tool for teachi ng Astronomy, Sci ence and Te chnology .................. 599 Ferran Salaza r et. al.: Simulatin g Atmospheric Turbulence : Code Devel opment and Ed ucational Applicat ions .......................... 605 Edwar , Shi ndi Marl ina Oktavi ani et. al. : Development of Commercia l - Off - The - Shelf Imaging Payloa d for Cl oud Coverage Monitori ng ................. 611 Júlio Santos et. al. : How to Manage a Rocket ry studen t projec t in f ull quar antine ..................................................................... 617 4 th Symposium on Space Educ ationa l Acti viti es Barcelon a, Apr il 2 022 XXV Wan Fa ris Aiza t Wan Aasi m et. al.: The Structur al Analysi s of Alai nSat - 1: An Earth Observation 3U CubeSat ................................................ 623 Joseph E. G. Middleton et. al .: Developing low - cost, reusable solar observation pla tforms to advan ce sustainable heliophysics research ................................................................................................ ............... 629 Zaria Serfo ntein et. al .: LEOniDAS Drag Sail Experiment on the 2021 ESA Fly Your Thesis! Parabolic Flight Campaign ....................................................................................................................... 635 Andreas Wolni evik et. al.: Lessons Learned when Developing a Hi gh Performance Attitude Cont rolled Platform to Achiev e Microgr avit y for Low - Cost Ex periments ..................................................................................................... 6 41 Mark Ang elo C. Puri o et. al.: On - boar d Image Classificati on Payload for a 3U CubeSat using Machine Learning for On - Orbit Cloud Detection ........................................................................................................................................................ 6 47 Slaveya Abadzh ieva et. al.: Universi ty of Not tingham St udent Space Activit ies to Enrich t he Traditional Cu rriculum ........................... 653 Stefanie Steinbach e t. al.: Earth obser vation ed ucation f or Zero Hun ger: A Massive Open Online Cou rse towards achievin g SDG #2 usi ng EO ............................................. 659 Esmée Menting et. al. : Lessons learnt during the REXUS program on how to manage a st udent Project .................................... 665 Mateusz Zalas iewicz et. al.: Flight Hard ware and Soft ware Operati ons Performance Review for BAMMsat - on - BEXUS – a BioCubeSat Prototype Flown on BEXUS30 ....................................................................................................................... 671 Muhammad Sh adab Kha n et. al.: Development and Fligh t Results of Tal Tech Univer sity Cu beSat Missi on ................................................... 677 Júlio Santos et. al .: Development of a Low - Cost Ground Segment Capable of Receiv ing Data from Nano satellites: a Partnershi p between Br azil and Portugal ..................................................................................................... 683 Thibault Gat eau et. al.: Nanospace and Open - source Tools for CubeSat Preliminary Design: Review and Pedagogical Use - case .............................................................................................................. 689 Riccardo Restivo Al essi et . al.: D esigning Greenhouse Subsystems for a Lunar Mi ssion: Th e LOOPS - M Project .................................. 695 Robert Jef frey et. al .: Teaching comput ational t hinking t o space sci ence student s ....................................................................... 701 Catho Schoenmaek ers et. al.: The effect of spacef light on the otolith - mediated ocu lar c ounter - roll ........................................................... 707 Alejandro Sans Monguil ó et. al .: Assessment of a machine - vision - assisted t est bed for spacecraf t ma gnetic clean lines s análisi s ............. 713 André Teixei ra et. al.: Competitio n, Researc h and Ext ension: The three app roaches to the Popularization of Small Sat ellite s in the Alt o Parao peba re gion in B razil. ......................................................................................................... 719 4 th Sympo si um o n Space Edu cational A ctiv ities Barcelona, April 20 22 Page 2 of 6 Acro nyms/ A bbreviations CNES Cent re Nat ional d ’Études Spatia les EASA Eur ope a n Aviat ion Safety Agenc y ESA Europ ean S pace Age ncy HEI Higher Educ ation Ins titute IAF Interna tio na l Ast ro nautic al Feder ation ISU Interna tiona l S pace U niver s ity SSP Summer Space Pro gram SEMA Spa nish Soc iety of Aer ospa c e Medic ine SGAC Space G ener at ion Advisor y Counc il ST EAM Scienc e, Tec hno logy, Engin eerin g, Arts and Mathemat ics UPC Univ er sit a t P olitèc n ica d e Catal unya VFR Vis ua l F lig ht R eg ula tio n s 1. Introduc tion Parabol ic f lights h ave be en conduc ted f or a long tim e as a wa y of perf orm ing shor t - tim e dur atio n experim ents and t ec hnic al dem ons tratio ns [1 , 2]. Airc raf t parabo lic f light s provide up t o 25 seconds of reduced gr avi t y . T h e y are used f or conduct ing shor t invest igat ions in Ph ysica l and Life Sci ences , both f or s enior res earc hers a n d for intern ationa l stu den t ex perim entat ion a nd m otivation, and pub lic outre ac h. W e repor t on educat ional ex per im ents conduct ed in the Barcel o na parab olic flight platfor m (Sabad ell Airport , Barc elon a, Spa in) with s ingle - e ngi ne aer obat i c airc raf t suc h as the CAP1 0B ( Figur e 1), ac hieving u p to 8.5 seconds of m icr ogravity in its cock pit. T he flight prof ile res ults co m ing from a s teady flight prof ile an introd uc tor y pull - up m aneuv er is perf orm ed at inc reas ed ac c elerat ion ( rou ghl y 3 - 3.5g for these airc raf t), pilo t r educes thrust and, with thr ott le or i dle e ngi nes the airpla ne f ollo ws the par abol ic tr ajec tor y of a f ree - f lying bo dy. As a conseq ue nce, af ter a shor t p hase of transiti on, m ic rograv ity is obta ine d for 5 - 8 seconds . After the reco ver y mane uver a t incr eas ed acceler ation ( 2.5 - 3g) , th e airplan e f lies agai n horizont all y to the gro un d lev el for s om e m inutes bef ore in troduc ing the next p arabo la. Durin g one f light m ission t ypi ca ll y 10 - 15 parab olas are per form ed. Lar ger airc raf t provide be twee n 2 0- 25 s econds of m icrogravit y thank s to a m ore powerf ul eng ine. T he European Space Ag enc y ( ESA ) h as used since 1 98 4 six t ypes of airc raf t to c onduc t its parab olic f light cam paigns [3]: the KC - 135, the Carav elle f rom C NES, the Russ ian Il yush in Il - 76 MDK, th e Ces sna Cit ation II, t he A irbus A - 300/A - 31 0 ' zero - g' f rom Nov es pace , a ll of them with 2 or 4 engin es. An im portant num ber of physic al an d lif e s ciences ex perim ent s ha ve been co nducte d sho wing the suc ces s of this k ind of ac ces s to m icr ogravit y. Our appr oac h is diff erent f rom the s ucc essf ull y previous l y r epor ted par ab olic flights as we propose the us e of a sm all single - engine aerob atic pl ane. T his k ind of airc raf t (Figur e 1) is cer tifie d t o co nduct th is m anoe uvr e a nd c ould also be us ed f or pr of ess ional experim ents, testin g tech no log y and educ atio na l an d outreach c am paig ns as wel l. H ypogr avit y is exper ie nced with in the c ock pit for about 8 seconds with a flight prof ile sig nificant l y diff erent f rom that of larger airc raf t [4] . Figure 1 . Mudry CAP10B aerobatic aircraft u sed for educat ional p arabo lic fli ght campaign s. (Credit : Bar celona - Sab a dell A viation Club) Parabol ic f lights ha ve been us ed ver y succ essf ully b y the space agenc ies to cond uct student c am paigns with the aim to m otivate the youth to tak e part i n a ero naut ical and spac e resear ch. T his projec t is inspir ed b y the ES A Aca dem y hands - on e ducat iona l pr ojec ts and , in particu lar, b y the very succe ssf ul ESA F l y Yo ur T hesis Pr ogram [5 ]. 2. Object i ves T he objec tives of par ab olic f lights wit h a n aerob atic si ngle - en gin e air c raf t are as f ollo ws [4, 6 ]: 2.1. Sc ientific & Res ear ch - T o stud y differ ent proc es ses in whic h abr upt changes of gra vit y work load are app lied. In particu lar h y p er ( 3 – 3. 5g) to h ypograv it y (0.05g), and h ypo to h y p er grav ity per iods. 4 DOI: 10.5821/conference-9788419184405.001 4 th Sympo si um o n Space Edu cational A ctiv ities Barcelona, April 20 22 Page 3 of 6 - T o analyse trans ien t phenom ena that m a y occur af ter shor t periods of h y p er an d hy pogr avity . - T o allow exp erim ents for testing t he e quipm ent in a real para bo lic f light, with t he op portun it y to m anuall y int eract w ith the equ ipm ent and provide a proof - of - c oncept bef or e acces sin g other m ic rogravi ty r esearc h platf orm s. - If the ex perim ent can be r un in less than 8 seconds of expos ure to hypo grav it y, and t he residua l acc elerat ion of 0.05 g is accept abl e, then qua nti tativ e and q ua litati ve m easur em ents can b e m ade, t hus prov idi ng m eani ngful dat a. T he parabo lic fl ight can prov ide u p to 20 para b olas in a s ingle f light , and weather perm itting t he pr ocedur e c an be r epeat ed i n a single d a y. - In regards to h um an ph ysiolog y or ph y s ical experim ents in which a nd the h ypo and hypergr avit y en viro nm ent pla ys a role, t he fac ilit y enables dif fer ent experim e nts to be tested ins ide th e coc k pit, o ne b y on e on board (Figure 2) . More i nform ation can be f ound at our laborator y website ( C Sm icrogLab.u pc.edu ) Figure 2 . Human re producti on studies conduct ed in t his platfor m [7 ]. (Credit: Institut Dexeu s, UPC & Ba rcelona - Sabadel l Av . Club) 2.2. T ec hnologic al - Asses sm ent of technolo gica l equipm ent behav iour in a hyper and h ypogr avit y environm ent with abrupt c hanges in a tin y environm ent. - Safet y ass essm ent of exper im ents and techno logic al dem ons tratio ns w ithin a par abol ic flight aircr aft cock pit. - T raining of wann abe or f uture astr onauts f or for eseen pri vat e or p ublic s pace m iss ions. 2.3. Educ ati o n & Outreac h - Allow ing st udents to conduc t han ds - on experim ents in a re al weight less ness experie nce. - Increas ing the ir int eres t for stud ying Sc ienc e, T echnolog y, Eng ineeri ng , Arts and Mathem atics (ST E A M) s yll abus, in par ticu lar in the aer ospac e fie ld. - Provid ing s tu dents fr om diff erent ba c k grounds and natio na lities with the oppor tun it y of work ing as a te am with a c omm on goal, while i nteract in g with sp ace pr ofes sion als. - Raisin g pub lic i nterest in s pac e resear ch. - Creat ing th e oppor tun it y for stud ents to wr ite and pr esen t t heir s pace r es earch in rele vant journals and c ongress es, and also to f urth er appl y to the s pace ag encies e duc ation al program s building up the ir cur riculum . 3. Chall enge- B ased L earnin g Challe nge - Based Lear ining (CBL) is a ST EAM Educat ion m et hodolog y that has been r ecent l y introduc ed as a c o llabor a tive an d hands - on appro ach to enc our age s tuden ts to put t he ir k nowledge in pr act ice b y address ing r eal - lif e problem s. In 2008, the c o ncept C BL was f irs t nam ed b y the techn ol og y ent erpris e A pp le® as a m ethodo log y to m e et the XX Ist C ent ur y dem ands [8 ] . Higher Educ ation Ins titutio ns (HEIs) have s een in the re c ent years ho w their role had to ad apt i tself to th e arisin g chang es in our societ y and in pa rtic u lar, ST EA M Univers ities [9]. O ur c olle ges ar e becom ing fac ilitators f or the st uden ts’ train ing, incl uding in their s yllabus c om petenc ies (s uch as team work, creativ it y or inn ovati on sk ills) to be ac quir ed, which ar e requ ired in n o wada ys’ sci entif ic endeav ours . Spac e Edu cation is a fie ld particu larl y suited t o ap pl y CBL, w ith han ds - on res ear ch pr ojec ts req uiri ng s tud ents t o work with te am m ates , ment ors and exper ts. T he y ar e expect ed to tak e ac tions an d c omm unicate their eff orts in a m ulticultural, i nter nation al s cenar io in order to pr oduc e an optim al response a specif ic goa l. W e her ein prese nt a succ ess f ul CBL Cas e Stud y which invo lves des igning, im plem enting, and ac tual ly f l ying a m icr ogravit y exper im ent in parab olic f light . 4. T he Barcel on a Z eroG C ha llenge T he Barcelon a ZeroG C hallen ge is an internat ion al c om petitio n ad dres sed t o Uni ve r sit y stude nts worldwide (F igur e 3) . It requires the st udents to b uil d a te am with a m entor, pr opose, d esig n, build and fl y th eir experim ent in m icr ogravit y and fina ll y anal y ze the resu lts an d c omm unicate their find ings. 5 DOI: 10.5821/conference-9788419184405.001 4 th Sympo si um o n Space Edu cational A ctiv ities Barcelona, April 20 22 Page 4 of 6 Figure 3 . Barcel ona ZeroG Challenge announceme nt. (Cre dit : S GAC ) T he experim ent has to m eet t he r equ irem ents of a par tic ular platf orm of micrograv it y rese arch availab le in Barc elona f or educ a tion al and resear ch pur pos es [10 ] . More t han f if ty stud ents h ave a lread y f lo wn t heir experim ents on bo ard an aero bat ic C AP10 B aircr aft in Barcel ona in p revious e ducat iona l cam paigns; havi ng pub lis hed t heir r esul ts in relevant s y m posi um s and sc ientif ic j ournals [4] . T hese cam paigns, insp ired b y the wel l - k nown ESA Stude nt’s P arabo l ic Fligh t cam paigns , have at trac ted m edia attent ion and h ave prom oted pub lic a warenes s on ST EAM st udies as wel l. Four pr ev ious e diti ons of the B arcelon a ZeroG Challe ng e have t ak en plac e sinc e 201 0 , with a si gnif icant num ber of the Inter nat iona l S pace U n iv ers it y (I SU ) st u dents b ei ng in volved [11 , 12 , 13 , 14, 15 ]. T hree work shops had b een held in th e Summ er Space Progr am and in th e Master S pace Progr am of ISU. A new ed it ion of this contes t is und er way [10 ], with the winner s ex pect ed to f l y their ex per im ent in 2022. T his editio n is organi zed by U niv er sit at P olit èc nic a de C a talun ya (U PC), t he Barcel ona - Sabade ll Aviation C lub and SG AC, t he Space Gen erat io n Advisor y Counc il well - k nown stud ents assoc iation. Mu lti disci plin ar , d iver se an d m inor it y team s of students were enc o urag ed to appl y. An i ndep en dent panel of experts fr om the European S pace Agenc y (E SA) Aca dem y conduct ed the fin al se lec tion of the winner team . In the c urrent ed iti on, the s electe d students ’ t eam r eceives a 2500 eur os gr ant to devel op its exper im ent, as we ll as the opport unit y to fly it in parab olic flig ht. A n unprece dent num ber of 15 pr oposa ls ha ve been receiv ed. St ude nts f rom 2 3 dif f erent countr ies subm itted th eir prop os als ( 60% lif e sc iences experim ents; 40% ph ysic al s cie nces) . Am ong the partic ipa nts 6 3.3% c ame f rom Europe, 14.3% fr om Am erica and 1 3.4% f rom As ia. T he winner team c onsists of four fem ale student s fr om the U nivers ity of Antioq uia: Lu isa Fernand a Me ndoza (s pok es person) , Paul ina Quint ero, Or ian a Mejía and Mar ía d el P ilar Monsa lve. T he team is called ‘Vera G rav itas’, which in La tin m eans ‘true gravit y ’ , a nd it a ls o ref ers as well to Dr. Ver a Ru bin, a f am ous astronom er who m ade im portant c ont ributi ons to sc ience [16] . T he y ar e par t of the Co lom bia n Assoc iation of W o m en in Aerospace , which aim s to ar i se wom en' s inte rest in th is s cience. T he team also has a m ent or, Prof es sor Lil iana Marcela Bust am ante G oe z, from the Departm ent of Mecha nica l Engin eering at th e Univers it y of Antioqu ia (F igure 4 ). T heir propose d ex per im ent is en titled "De posit io n of tin d r ople ts on elec tro nic com ponents i n the absence of grav ity." Figure 4 . ‘ Vera G ravitas ’ Team, w inners of the Barcelona Z eroG Chall enge 2021. T he experim ent seeks to stud y how sol deri ng electron ic c om ponents is aff ected b y m icrogravi ty, a res earc h t opic th at m a y have m an y app lic ations in the near f uture. Cur rent l y, this te am is work ing with t he advic e of resear cher s f rom UPC and experie nced pi lots fr om the Bar celon a - Sabad ell Aerocl ub in order to devel op their exper im ent, ada pt it to the cock pit of the p lane a nd f l y it th is year 20 22 at Sabade ll A irport. T he t eam is also en gaged i n an outr each proj ect to d iff use the ir find in gs [1 7 ]. Further m ore, s tudents f r om our o wn Un iver sit y, have also the opp ortun it y of des igning and testi ng t he ir exp er im ents durin g t heir s tu dies with a s ingu lar han ds - on tr aini ng and a n i ntroduc tion to s pac e res e arch [4, 11]. Mas ter and Doc tora l T hesis are good f ram eworks to include s tud ents’ a dvanc es and contr ibute to their gr adu ation wit h a si ngular ex p er ie nce. 5. Discus si on W e first reported a su c ces sful ser ies of parab olas perf orm ed wi th a lig ht sin gle - engine aerob atic plane with a l ife s cienc es ex per im ent on boar d. Between 5 to 8.5 s econds of m icrogravi ty wer e achiev ed with a lim ited operat ional cos t. T he opt im ization of the m anual piloting has m ade possib le to pro vide a qua lit y of g b et ween 0.05g an d 0. 005g with a g j itter reductio n depend ing on t he st ren gth of win d 6 DOI: 10.5821/conference-9788419184405.001 4 th Sympo si um o n Space Edu cational A ctiv ities Barcelona, April 20 22 Page 5 of 6 gusts . Ver y lim ited tim e is ne ede d to pr epare and pe rf orm the exp erim ent so this appr oach is specif icall y su ited for t hos e k ind of r apid protot yping techn olog y tes ts, or sim ple experim ents that do not need hug e or sophist icated e quipm ents. T hese par abo lic flights ar e not des igned to com pete with those f r om space agenc ies requ iring larg er airc raf t, instea d, the y r ather ext end t he ra nge of possibi lities a vail able to the r ese arc hers and students inter es ted in m icrogravit y rese arch. Am ong the lim itations of sm all aerob atic a irc raf t are: lim ited cock pit s ize, red uc ed hypo grav it y tim e, no electr icit y p lugs availab le, onl y one experim enter at a s ingle f light, higher g j itter sensiti vit y and a m or e aggr ess ive f light prof ile. Howe ver, f r om the po int of vie w of pr ovid ing a hands - o n exper ienc e to stu dents it h as pr oven very s ucc essf ul at a reas o nabl e cos t. Educat iona l acti vities ha ve been f rom the beginn ing an ess ent ial par t of our m otivation, and ha ve pro vide d m eani ngful r esul ts and a num ber of f light oppor tu nit ies f or st udents ’ experim ents, as well as tutori als af ter d at a colle ct ion . Only t wo m ild episodes of motio n sic k ness have been r eport ed in m ore than 10 years of educti onal ac tiv ities. The vis ual f light conf igurat ion of th is p latf orm allows th e partici pant an y inconven ien ce durin g the f light , and foll owing t he pre - es t abli shed prot oc ol, he or she woul d be safel y held on ground i n less than 15 m inutes with s peci ali zed m edical car e availab le on site. Mand ator y safet y brief ings are conduct ed pr e and post - f ligh t. Students ’ as soc iations s u ch as the Spac e Generat ion Adv isor y Co uncil ( SG AC), are curr entl y invol ved in this e ndea vour. Som e of the pr ior p artici pant s h ave dec lared the ir excitem ent for hav ing t he o pportu nit y of ac tua ll y m aking s pace r ese arch in m ic rogravit y, provid ing outr each t o th e pub lic, and l ater pub lish ing th e res ults in s elected c onfer ences and ind exed j our nals. T hree ke y factor s to s ucc ess have bee n ide ntif ie d f r om our years of experienc e: 1 - A s trong inv olvem ent of stude nts ' ass ociati ons, 2 - Interna tiona l cooper atio n and 3 - Q ua lit y o f students ' m entor ing. Space stu den ts as soc iatio ns are one of the m ost valuab le as sets in th e astr onautic al f ield t o prom ote m otivation, m entori ng and a m eaningf ul career for their m em bers . The y spread th e word of the opport uni ties t hat eventu all y arise, and pr ovide an im po r tant contac ts net work which ar e ess ential to bu ild up a divers e team such as that req uested in th is singu lar cha lleng e. Int ern ationa l coop erat ion involves m aking us e of t he prof ess ional societi es s uch as IAF to r eac h the nec ess ar y stak eholders f or star ting and m antaining an educat ional en dea vour. Last bu t no t leas t, in t he cas es that a high l y involve d m entor was engag ed with thei r students pr ojec t, ther e was a un ique bo os t to the qual it y of their res ea rch pr oduct. S om e m entors even att end ed all briefings , supervise d the experim ent in a particul ar fiel d in which the y were rec ogn ized ex perts a nd resear chers , an d contribu ted subs tant iall y t o the suc ces s of t heir students . 6. Conclu sions W e have reporte d on th e educat io nal an d outreach ac tiv ities of an inn ova tive m ic rograv it y platfor m based on s ingl e - engine aer obatic planes in Barce lon a ( Spai n) which is o ngo ing, m aking a s ignif icant im pact a nd insp iring students ar ound th e world t o get an int eres t on space m edicine and r ese arc h. T heref ore, we plan to c onti nue these activ ities an d ex pan d them in t he near f utur e. Am ong the les sons learned, t he s tuden ts ’ in volvem ent a nd internat ion al co operat ion h ave been th e m os t im portant f act ors that ha ve le d t his p latfor m succ essf ul. Goo d m entor ing is a k e y factor f or th e succ ess of stude nts i nvol ved in com plex Challe nge - Based Lear ning act ivities . Ackno w ledgements Man y peopl e have contr ibut ed over t he y e ars to these B arcelo na para bo lic flights w ith sing le - engine aero bat ic aircr af t. In par ticu lar, we w ish to thank our colleag ues f rom the Barcelo na - Sabade ll A viati on Clu b and thos e flig ht surgeons f rom the Spanish Soc i e t y of Aerospac e M edic ine ( S EMA ) w ho have volunt eere d contr ibut ing to the s af ety of operat ions . W e are lik ewise gratef u l to al l th e students and f light part ic ipants a nd the ir m entors for their s upport a nd contr ibut ion, a nd also to SG AC and E SA Academ y for their curr ent inv olvem ent and supp ort. Pr evi ous partici pat ion of som e of the a uthor s in ES A hands - o n educ at ional acti vities ha ve bee n a great sour ce of inspir ation. 7 DOI: 10.5821/conference-9788419184405.001 4 th Sympo si um o n Space Edu cational A ctiv ities Barcelona, April 20 22 Page 6 of 6 Referen ces [1] V. Pletser , J . W inter, T . Bret - Di bat, U. Friedric h, J. C ler vo y , T. G harib, F. G ai, O . Minster a nd P. Sundb la d, “T he Fir st J oint European P artia l - G P ar abolic F lig ht Cam paign at Moon a nd Mars G ravi t y Leve ls f or Sc ienc e and Explor ati on” , Micrograv ity Sc ienc e and Tec hnology , 24 (6), 3 83 - 3 95 (20 12). [2] V. Pletser , S. Rouquett e, U. Fr iedr ich , J . Clervo y, T . Ghar ib, F. G ai and C. Mor a, “Europe an par abolic f ligh t cam paigns with Airbus zero - g: Look in g back at the A300 a nd look ing f orwar d to th e A310.” Advances in Space Resear ch , 56 ( 2015 ) 1003 - 1013. [3] V. Pletser, “ Short dur ation m ic rogravit y experim ents in ph y s ica l an d lif e sc iences during par abo lic f lights : th e f irs t 30 ESA cam paigns”, Acta Astr onau tic a , 55 (1 0), 829 - 854 ( 2004) . [4] A.Pe re z - Poch, D.V . Gon z ález and D . López, “H ypogra vit y re searc h an d educat ional para bo l ic fl ight act ivit ies in Barcel ona: a n e w hub of innov ation in Europe” , Mic r ogr av ity Scienc e an d Technol ogy . ( 2016) do i: 10. 1007 /s122 17 - 016 - 9516 - 7 . [5] N. Calle ns, L. Ha and P. Gal eone . “ Benefits of ESA G ra vit y -R elated H ands - on P rogr am m es f or U nivers ity St udents ’ Careers .” Microgr avity Scienc e a n d Technol ogy , 28, 5 19 - 527 (201 6) doi: 10.1007/s 1 2217 - 01 6 - 950 5 - x [6 ] M. Brigos, A. Pere z - Poc h, F . Alpist e, J . T orner, “ Parabolic flights with s ingl e - engine a eroba tic airc raf t: f light prof ile an d a com puter s im ulator f or its optimi zation”, Microgr avi ty Scienc e and T ec hno logy , 26 (4) 229 - 2 39, (2 014). [7] M. Boada , A. Pere z - Poch , M. Ball ester , S. Garc ía - Mo nclús, D .V. Gon zález , S. Garc ía , P.N. Barri , A. Ve iga , “ Microgr avit y eff ects on f ro zen hum an sperm samples . ”, Journa l of Assis ted Reprod uctio n and Ge netic s , 37, 2249 - 2257 ( 2020) . [8] M. Nic hols , and K. C ator , “ Chall enge - Based Lear ning ” W hite paper . A pp le, Inc . (2008). [9] UNESCO . Re th ink ing E du cation . ISB N 978 - 92 -3 - 100088 - 1 (20 15) . [1 0] The Bar celo na Zer oG C hall enge 2 021, http:// windo w2th eun ivers e.or g ( las t acces sed 3 - 202 2 ). [11 ] M. Azem à, “ Stud y of the fus ed deposi tion m odeling beh avior u nder m icr ogravit y condit ions ”, Master Thes is , Univers it at Politècn ica de C ata lun ya (2 014). [12 ] H. Allawa y, A. Melynsh yn, A. Kindrat, J. Muller, A. Pere z - Poc h, D.V. Go nz ález, R. T hirsk and G. Clém ent, “Per cept ion of am biguous im ages on weightle ssness” . Proceed ings of t he ELG RA Symp osiu m , Antwer p (20 11). [13 ] G. Clém ent, H. Alla wa y, M. Dem el, A. Golem is , A. Ki ndr at, A. M elin y sh yn, T . Merali an d R. T hirsk , “Long dur atio n spacef light incre ases dept h am biguity of reversib le per spec tive figur es ”, P los On e 10(7): e01 323 17 (2 015), doi: 10.1371/jour nal.pone.0132317. [14 ] J.R. O sbor ne, M.A. Alo nsopére z, D . Ferr er, N. G os wam i, D.V. Gon zález, M. Moser, V. Gr ot e, G. G arc ía - Cuadr ad o and A. Pe re z - Poch, “Eff ec t of Menta l Arithm etic on he art rate res ponses duri ng Parabol ic F lights: t he Barc elona Zero - G Challe nge”. Microgr av ity Science an d Technol ogy , 26 (1), 11 - 16 ( 2014). [1 5 ] A. Schuster , V. Bocc ia, A . Perez - Poch and , D. V. G onzá lez, “E st im ation of relativ e dista nce bet wee n two obj ects i n m icrogravi ty c onditi ons d ur ing par abo lic flig ht” , Proceed ings of the Elgr a Sympos ium . Corf ú, Gr eece (2015) . E lgr a News 31, p.1 65 (2 015). [1 6 ] Vera Gra vitas T eam ( in Spanish) https:// www . youtube. com /watch? v= yoP0 9O3gs58 (last ac ces sed: 3 - 2022). [17 ] Vera C ooper Ru bin. Sm iths onian Nationa l Air and Spac e Muse um . https://a iran dspac e.s i.ed u/ex plore - an d - learn/t opic s/ wom en - in - aviat ion/ru bin.c fm (la st accessed : 3- 2 022). 8 DOI: 10.5821/conference-9788419184405.001 4 th Symposium on Space Educational Activities Barcelona, April 2022 Final testing, pre-launch activities, launch and post-launch analysis of a sounding rocket made by students in Spain Alba Badia Rifà , Daniel Cantos Gálvez , Adam El Ghaib Bougrine 2 , Javier Hidalgo Marí 2 , 1 2 Marc Martí Arasa 2 , Arnau Pena Sapena 2 ________________________________________________________________________ Abstract This paper summarizes the final launch preparation tests, the operations before, during, and after the launch, and the results of the launch of a supersonic sounding rocket developed by university students in Spain with the collaboration of INT A (National Institute of Aerospace T echnology). The students are part of the Cosmic Research association, based at the Polytechnic University of Catalonia ESEIAA T , and the rocket is called Bondar . INT A is a Public Research Organization under the Spanish Ministry of Defense dedicated to scientific research and development of systems and prototypes in the fields of aeronautics, space, hydrodynamics, security , and defense. The staff of the El Arenosillo Experimentation Center (CEDEA) collaborated in the Bondar mission with their knowledge and launch capabilities. The launch of the rocket took place on the 30 th of November of 2021. T wo students from BiSky , a rocketry team from the University of the Basque Country , also participated in this project, specifically in the development of the on-board and ground-based avionics subsystems. The paper presents information on the mission systems, the operations before, during, and after the countdown to the launch, the documentation required by INT A-CEDEA for the launch, and the results of said launch. In short, the systems developed by Cosmic Research for the launch are: the rocket, the launch pad, the rocket transport box, the flight simulator , and the ground-based rocket tracking station. The documentation required by INT A includes: a detailed description of the systems, a ground risk assessment, a flight risk assessment, structural analysis, aerodynamic analysis, and a list of countdown operations. Launch post-analysis activities evaluate the performance of systems and operations during the most critical phase of the mission. The Bondar Mission, due to its technical and operational complexity , was the most ambitious project ever developed by students in Spain in the field of rocketry . After a successful launch, Bondar became the highest-flying Spanish student-made rocket, with its apogee around 8 km AGL (Above Ground Level). Keywords INT A, launch operations, sounding rocket, Spain, students. ______________________________________________________________________ 2 Cosmic Research, Spain 1 Cosmic Research, Spain, [email protected] Page 1 of 6 9 DOI: 10.5821/conference-9788419184405.002 4 th Symposium on Space Educational Activities Barcelona, April 2022 Acronyms/Abbreviations CEDEA Centro de Experimentación De El Arenosillo CR Cosmic Research ESEIAA T Escola Superior d’Enginyeria Industrial, Aeronàutica i Audiovisual de T errassa INT A Instituto Nacional de Técnica Aeroespacial 1. Introduction CR (Cosmic Research) is a student association founded in 2016 with the mission of launching suborbital rockets for the benefit of society . Since its foundation, the CR’s team has launched 37 rockets and more than 100 CanSats. With the launch of Resnik in 2017, the association set the Spanish altitude record at student level, achieving an apogee of 2 km. Following its trail, the Bondar mission was started in 2020, whose goal was to develop all the technologies necessary to launch a stratospheric rocket. This paper aims to give an overview of the steps followed up to the end of the launch campaign. 2. Mission Systems 2.1. Rocket Bondar is a 2.6 m long, passively stabilized, supersonic, aluminum rocket. It is fitted with custom avionics for apogee detection and separation, and data downlink. It is a sounding rocket with payload capabilities up to 0.5 kg. Figure 1. Bondar rocket 2.2. Launchpad Horizontally-stabilized structure with variable elevation angle. It is formed by a six meters tall tower and rail to provide mechanical guidance for the rocket during lift of f. Figure 2. Launchpad 2.3. Rocket transport box A 2895 x 580 x 690 mm wooden box filled with custom antistatic and antivibration foams fitting the rocket shape that prevents it from sliding to ensure safe transportation during operations. Figure 3. Rocket transport box 2.4. Flight Simulator CR’ s own simulator is a 6-Degrees of Freedom stochastic simulator based on MA TLAB, which uses semi-empirical aerodynamic models to predict the rocket trajectory . 2.5. Ground-based rocket tracking station T wo antennas were installed on CEDEA ’s optronic systems to process the in-flight telemetry data by a custom made ground tracking station and send this information to the control center . 3. Operations In this section, the operations before, during, and after the countdown will be presented. These operations start with the review after transport of all the systems of the mission and end once the team arrives at the headquarters after the launch. 3.1. Pre-launch operations This group is the most extensive. It comprises activities before arriving at CEDEA and also operations in the spaceport. First of all, there is a review of all the mission systems. When all the systems are checked, the launch campaign officially starts. This is followed by the sorting and packing of all the components. Then the team proceeds to the transportation. Once in the spaceport, there is the assembly of all the systems, with the exception of the motor , the electronics bay and the recovery bay of the rocket, which are reserved for the launch operations. During this phase, 3 tests were conducted. The verification of the data reception regarding the avionics and the ground stations, the data injection verification and a launch operations Page 2 of 6 10 DOI: 10.5821/conference-9788419184405.002 4 th Symposium on Space Educational Activities Barcelona, April 2022 simulation. When all the tests were passed, the last step was the flight trajectory simulations. 3.2. Launch operations The launch operations start with the motor assembly and end when the motor is ignited. The most critical operations are reserved for this period. In short, these activities are, in chronological order: the assembly of the motor , the final assembly of the recovery bay and electronic bay with the rocket structure, the introduction of the motor inside the rocket, the transportation and placement of the rocket in the launchpad, the final avionics tests and simulations, the introduction of the ignitor , the final security checks regarding the drop area security footprint of the spaceport, and the ignition of the motor . Since this group includes the most critical operations, it was necessary to detail also the holding operations, the GO/NO-GO criteria and the emergency procedures. The holding operations comprise all the procedures that solve a possible problem during the countdown. Their importance derives from the necessity of knowing in each moment how to solve a problem, given the tension of the countdown period. Also, it is extremely important to know how much time it can take to solve a problem in order to decide whether the launch operations should be postponed until the next launch window or not. The GO/NO-GO criteria includes all the conditions that must be met in order to authorize the start of the launch operations. Some examples are: to not surpass the wind limits defined by the simulations, to have favorable weather conditions, to have all the systems ready and all the flight permissions. The emergency procedures include the instructions to follow if one or more of the potential risks of the launch operations occur . All the team members must be familiarized with these protocols and must have a copy with them. 3.3. Post-launch operations These operations start once the motor is ignited and finish when the team arrives at the headquarters. They are divided into two groups: the post-launch operations at the spaceport and the post-launch operations outside of it. The post-launch operations at the spaceport start with the lift of f of the rocket. It leaves the launchpad at an approximate velocity of 40 m/s. The powered flight lasts 6 seconds, in which the motor burns all its propellant. Then, the motor runs out of propellant and it continues its ascent for approximately 30 seconds. Once the rocket reaches the apogee, the avionics command the separation of the recovery bay from the avionics bay and the drogue parachute is released. At the same time, the motor bay and the recovery bay are discarded into the sea. The upper stage descends at an approximate velocity of 17 m/s for 8 minutes and then it is recovered from the sea. Figure 4. Post-launch operations Once the avionics bay is recovered, the electronics team proceeds to recover all the electronic components and the SD card. They return to the spaceport and the team starts sorting and packing all the systems. Finally , the team proceeds to the transportation of all the material to the headquarters. 4. Documentation The safety requirements set by the launch site demanded the production of various documents to ensure system integrity and operational safety before, during and after the launch. 4.1. System description T o better understand the Bondar rocket and serve as reference, a detailed description of all the components of each system was provided, including dimensions, materials, and other complementary information. 4.2. Ground Risk Assessment For security reasons all risks that might interfere with the mission were identified, assessed, and classified. The risks were evaluated taking into account severity and Page 3 of 6 11 DOI: 10.5821/conference-9788419184405.002 4 th Symposium on Space Educational Activities Barcelona, April 2022 frequency , following a method proposed by INT A [1][2], to ascertain their criticality . These values were used to determine if mitigation strategies were necessary to reduce their criticality to an acceptable level. The estimations were based on CR’ s previous work and other reliable documents. T o ensure quality the document was reviewed by both INT A and ASPY , a risk prevention company . 4.3. Flight Risk Assessment Following the same line of work as the ground risk assessment, this document compiles all the risks associated with the flight of the rocket. It includes, but is not limited to: motor explosion, premature separation of recovery devices, structural failure (specially the fins and their supports), pitch-roll coupling, high roll rates, and aeroelastic phenomena. CR’ s simulator was used to study some of these risks and propose adequate mitigation measures, but literature was also consulted for certain cases. 4.4. Structural Analysis For both the rocket and the launchpad a FMEA (Failure Mode and Ef fect Analysis) study was carried out, identifying the most critical failure modes and how to prevent them. For those failure modes related to mechanical overload, a FEA (Finite Element Analysis) was performed. The position and magnitude of the loads experienced in-flight for specific structural parts were determined with simulator data, and CAD models for those parts were designed. With these models, the NX Nastran Design solver was used, alongside Siemens NX software, to obtain the strain and stress profiles for all parts. These results were compared with the maximum yield values of the material, thus providing a theoretical Safety Factor , ensuring that the systems could withstand their expected loads. Other studied failure modes, making use of the Hyperworks suite, included: vibrational modes, local and global buckling, and fin and ogive overheating. 4.5. Aerodynamic Analysis The aerodynamic analysis of the rocket comprised many aspects. First, it offered a detailed description of the flight simulator , followed by the input parameters. The stability of the rocket was verified under nominal flight conditions, and the expectable values of certain parameters were studied throughout the flight, to serve as inputs for the structural analysis. Risks associated with aerodynamic phenomena were also studied. Finally , the trajectory of the rocket under variable weather conditions was studied for both nominal and adverse conditions (motor explosion, loss of fins, premature separation), to ensure the spaceport footprint was respected. 5. Results and discussion The data used to perform the analysis of the flight comes from three dif ferent sources: a. CR’s simulator: used during launch operations to predict the rocket trajectory and ensure safety . b. On-board avionics: developed by BiSky T eam, transmitted data every 0.3 s to the ground stations. c. INT A ’s tracking devices: of fer trajectory data at a 50 Hz rate, starting at 1.16 s into the flight due to a tracking error during lift-of f. 5.1. Acceleration Figure 5. Acceleration during ascent flight Figure 5 shows the absolute value of the acceleration during ascent flight. The acceleration phase lasts approximately 6 s, and the rest is deceleration. The readings obtained from the avionics and INT A are almost identical, except from the noise present in the latter due to the higher sampling rate. The divergence at the end is not significant and is attributed to the distance between the rocket and the tracking device. The simulator predicted a higher acceleration rate during the powered flight, which might not have been achieved due to subpar motor performance and higher drag forces. Page 4 of 6 12 DOI: 10.5821/conference-9788419184405.002 4 th Symposium on Space Educational Activities Barcelona, April 2022 The latter can be also observed in the deceleration phase. A higher peak after motor burnout indicates a higher supersonic drag, which quickly decelerates the rocket to the subsonic region (around 12 s after lift-of f). The simulator predicted a longer supersonic phase, lasting until around 15 s. Acceleration rates in the subsonic region are almost identical, which leads to the conclusion that drag discrepancies must be associated with supersonic drag (associated mostly to shock waves). The numerous bolts and rivets in the fuselage, as well as the voluminous fin supports are believed to be the origin of this increased drag. Ef forts in the simulator have to be made to adequately characterize the rocket drag (updating current models based on [3]), and constructive improvements are needed for future rockets. 5.2. V elocity Figure 6. V elocity during ascent flight. Raw data Figure 6 presents the velocity readings from the two ground stations. Station 1 did not receive consistent data at any point, while station 3 is not accurate during the majority of the flight, since it of fers a velocity profile characteristic of a two-staged rocket. The root of the problem has not been identified, and can be associated either with data reading, transmission or reception. Since acceleration readings are correct, the velocity will be obtained through integration (using an explicit scheme), taking into account the Euler angles (which define the orientation of the rocket). After manipulating the avionics data, the results in figure 7 show a better correlation with reality . The slight dif ference can arise from the acceleration discrepancies, inaccuracy of the Euler angles measured, or due to the numerical integration scheme. Figure 7. V elocity during ascent flight. Manipulated data The ef fects of increased supersonic drag can be seen also in this figure, since the change in slope becomes significant after around 300 m/s (in the transonic region). This strengthens the hypothesis presented from the acceleration data. The deceleration rates after going below Mach 1 are similar and the model for predicting subsonic drag (also extracted from [3]) is assumed to be accurate. 5.3. T rajectory Figure 8. Rocket trajectory Figure 8 shows the trajectory of the rocket according to the three sources. Once again, the level of accuracy of the avionics, as received by ground station 3, is high. However , Global Positioning System (GPS) data is not completely accurate during the higher speed segment of the flight. This causes the divergence towards the west during the ascent. If the time is taken into account, it could also be observed that the GPS information is lagging behind during this part, Page 5 of 6 13 DOI: 10.5821/conference-9788419184405.002 4 th Symposium on Space Educational Activities Barcelona, April 2022 were called "space weather operators", and the logo for the SWIC originates from there (Figure 1). Figure 1. SWIC Logo The Koninklijk Nederlands Meteorologisch Instituut (KNMI) joined in the development of the course shortly after . Now also the duty of ficers of the PECASUS [7] service follow the S W I C . PE C A S U S p r o v i d e s a d v i s o r i e s o n en h a n c e d s p a c e we at h e r ac t iv i t y fo r c i v i l aviation. The STCE supports this service in the fo rm of th e S WI C, whic h i s o pe n t o a ll PECASUS partners. The first SWIC took place in May 2017, with the fourteenth edition in March 2022. No courses took place in 2020 due to the outbreak of the COVID pandemic. In total, already more than 100 trainees took part in this course. The course is intended as an entry course on spac e we ath er . It pr ovi des a n el eme nta ry overview of the relevant aspects of space weather without invoking complicated background physics. The course is intended for meteorologists and space staf f that will be providing space weather information to military and civilian end users. Aside from individual participation, it is also possible for an institute to request a SWIC to be organized for their employees. Depending on the ir aca demic level, th e ins titute can choose to refresh certain physical and mathematical basics to allow the trainees an ea sie r u nd er st an di ng of th e S WIC 's main portion. This is called the pre-SWIC and is g i v e n b y t h e r e q u e s t i n g i n s t i t u t e i t s e l f . S i m i l a r l y , th i s in s t i t u t e ma y al s o el e c t to educate the trainees on the space weather ef fects on the specific equipment they handle (e.g. the military). This so-called post-SWIC takes place after the main SWIC and is again the responsibility of the requesting institute. For obvious reasons, the pre- and post-SWIC are not a systematic part of the main SWIC. The introductory course can be extended with topical modules or tailored to the specific needs, background level and interests of the participants. An end user from the aviation or telecommunication sector , for example, has other needs than a space weather forecaster in a solar research centre. The programme focuses on gaining knowledge by fact-learning and training skills through easily accessible methods like repetition and games. The on-site editions include a visit to the beating heart of our service centre and a ‘Meet & Greet’ with scientists and forecasters. SWIC has the tools to evaluate the participants and can provide an examination certificate. T h e S W I C i s t a u g h t b y q u a l i f i e d a n d experienced staf f with extensive expertise in relevant domains such as scientific research, so la r phy si c s, spa c e w ea t he r , f or e ca st i ng , engineering, communication and outreach, and teaching. Due to the COVID pandemic, the courses planned in 2020 were canceled as participants were unable to travel to the STCE. From 2021 onwa rds , we restar ted with a fully o nli ne version of the course. The encounters with S T C E s ci e n t i s t s w e r e r e p l a c e d b y g u e s t lectures and the exercises were reinvented using existing, easily-accessible online tools. The added benefit of having a fully online version of the course is that it allows us to reach an audience that cannot easily travel to Belgium. W e organized for example a tailored course for members of the United States Air Force for whom travelling to Belgium for a 3- day course is to o time-co nsuming. Online participation is also advantageous for environmental and climate reasons and to avoid extra financial costs. We plan to continue organizing the SWIC alternating between online and on-site editions. 3.1. Course Contents The content focuses on space weather and the ef fects on man-made infrastructure and its functionality . W e discuss solar eruptions of very high-energy matter and electromagnetic radiation, which in j ec t m a ss i ve amo u nt s of e ne r gy in t h e Earth's magnetosphere and ionosphere leading to pronounced impact on navigation, communication and energy transport. The basic concepts and drivers of space weather are described first, with an added overview of the different sensors used to monitor the activity . From the Sun, we move to the magnetosphere, thermosphere and Page of 3 5 20 DOI: 10.5821/conference-9788419184405.004 4 th Symposium on Space Educational Activities Barcelona, April 2022 i o n o s p h e r e a n d d i s c u s s h o w t h e y a r e impacted. The impacts on aviation specifically , in particular in the framework of PECASUS, is described in much detail on the last day of the course. B y t h e e n d o f t h e c o u r s e , t h e t r a i n e e s understand the basics of space weather and know about the potential impact on technology . The students are also able to understand and i n t e r p r e t t h e s p a c e w e a t h e r i n f o r m a t i o n p r o v i d e d b y t h e s p a c e w e a t h e r f o r e c a s t centers. 3.2. Didactic Methods The SWIC caters to a very diverse public, which are not always trained extensively in ma t h e m a ti c s an d p h y s i c s . W h i l e w e on l y expect a medium secondary school knowledge of mathem atics and physics, most of the p a r t i c i p a n t s h a v e w o r k i n g e x p e r i e n c e i n weather forecasting or engineering, and have an interest in natural and technical sciences. From time to time we have participants that are working as civil servants in risk assessment. Their knowledge of physics is usually limited, and then we adapt the course accordingly by e x p a n d i n g m o r e o n t h e b a s i c p r i n c i p l e s . Everyone is required to have a good working knowledge of English since that is the teaching language. In th e co u r s e we fo c u s o n th e ph y s i c a l principles of space weather without working out the details mathematically . There are little to no equations shown in the course notes. All principles and concepts are explained verbally and with graphics and movies, making use of co mp ar is on s t o k no wn conc ep ts whe re ve r possible. We intentionally keep the number of participants low (up to 8 trainees per SWIC in the more recent editions) such that we can monitor their understanding and progress closely . The on-sit e course comprises three d ays, while the online course is spread out over four days. There is a huge amount of material for the students to absorb. W e found that when teaching online it is harder for the students to concentrate for an extended period of time, also because we cannot do site visits in this case, which tend to make the day somewhat lighter . Therefore, we spread the online course over more days. For the on-site course the trainees have to travel to the STCE and so it is best to comprise it into fewer days to reduce the total time spent on the course. Starting 2022, the concluding online evaluation of the course was moved to the week after , so that there is more teaching time left and the trainees have more time to study the course material before being tested. Throughout this week the teaching staff is available to answer any remaining questions. In the course of a lecture day , we alternate between didactical methods and tools. The basic principles of space weather are mostly explained through direct teaching, aided by presentations. The three experienced teachers that are responsible for the bulk of the course c o l l a b o r a t e c l o s e l y t o h a r m o n i s e t h e i r presentations. They also make sure to involve the audience through questioning and interactive slides, and encourage questions from the trainees. The program alternates these teaching periods with exercises, games and recapitulation moments. The main c o n c e p t s a n d p r i n c i p l e s a r e r e p e a t e d constantly such that the students can absorb the theory simply by attending the course. The trainees also have their own job to attend to and will have little free moments to spend on studying outside of the course time. We anticipate this by including the repetition in the course program. T h e e x e r c i s e s i n c l u d e h a n d s - o n m a t e r i a l where the students work with real-life space weather data and learn to interpret them. The g a m e s s u ch as pi c t i o n a r y , t a b o o , ri n g i n g su n s p o t s [ 8 ] an d b i n g o a r e me an t as a moment to relax and bond, but also serve as an opportunity for questions, recapitulation and repet ition . Duri ng the se exe rcise s we c an c o r r e c t a n y m i s i n t e r p r e t a t i o n s a s w e l l . Additionally , each course day starts with a recapitulation of the previous day and a Q&A session. For the online version of the exercises, we use G o o g l e J a m b o a r d s [ 9 ] , w h i c h a r e f r e e interactive whiteboards on which the students can work together . The courses are taught using the Zoom teleconference software [10] and we use many of the interactive features there such as the annotation option to make explanatory drawings, the breakout rooms to allow students to work on the exercises in small groups and the poll feature for quick tests. The final evaluation of the trainees takes place online through the STCE website. The slides of the presentations are provided to the students and serve as course notes. They are accompanied by explanatory text, of which the content is much broader than what was discussed during the course itself and which includes useful links. The slides serve as a Page of 4 5 21 DOI: 10.5821/conference-9788419184405.004 4 th Symposium on Space Educational Activities Barcelona, April 2022 reference for the trainees when executing their future job interpreting space weather forecasts. 4. Discussion, feedback and reflections Throughout the SWIC, much attention is spent on feedback from the students. At the end of each day and at the end of the course, we ask the trainees for their reflections, comments and suggestions. For the students that prefer to share their opinion in private, we invite them to do so once more when we deliver them the course certificate. The teaching staf f can easily be contacted by the trainees and actively encourage the students to reach out with questions and feedback. Throughout the years, this open attitude has allowed us to improve the course, for example in refining the order in which the dif ferent subjects are tackled and adding extra course time at the start to introduce basic concepts that are needed throughout the course. Also, when transitioning to the online version, t h e fe e d ba c k o f th e s t u d e n ts wa s m u c h needed, for example on which online tools were easy to use and accessible to them. Note that some work in restricted environments where the installation of new software is not allowed. After each edition, the teaching staff holds a meeting to critically evaluate the SWIC and to plan the next one. In these meetings exercises and course material are fine-tuned. One of the decisions that came out of them is to decrease the number of participants in the more recent editions, allowing for a closer monitoring of the students as well as more interaction between them. 5. Conclusions and Outlook The SWIC has been a major success for the STCE, allowing us to reach a new public of meteorologists and aviation staf f. The STCE a l r e a d y h a d a s t r o n g p o s i t i o n i n p u b l i c outreach and communication towards the solar scientific community , yet it is very hard to cross the borders to other disciplines. Space weather is by definition an interdisciplinary science with a broad range of impacts. Through the SWIC, we can raise the awareness of other research institutes, companies and nations to space weather threats. The continued interest in the course shows there is a real need for this t r a i n i n g . T o o u r k n o w l e d g e , t h e r e i s n o equivalent to it in Europe, even worldwide. In the future we plan to diverge to tailored courses. In 2021 we organized a custom SWIC for the United States Air Force, focusing in a limited time span on the topics that were of most use to them. We plan to continue on this route by providing, in addition to the regular SWIC that is now on point, one-day topical SWICs focussing on ionosphere, aviation or high-frequency communication. A one-day , specialized course may also attract interested trainees that are unable to free up multiple days in their busy work schedule. Acknowledgements T h i s w o r k w a s s u p p o r t e d b y t h e S o l a r - T errestrial Centre of Excellence. We thank our partners of the Royal Netherlands Air Force (RNLAF) and the KNMI, for their help in setting up and continuously improving this course. The S W I C h a s b e n e f i t e d g r e a t l y f r o m t h e contributions of its guest speakers and the guides of the site visits, but also from the generous feedback of all participants up to now . References [1] SWEC: https://www .stce.be/SWEC , last visited: 15th March 2022. [2] P . V anlommel et al.,, Exploitation, dissemination, education and outreach in the frame of the COST action ES0803 "developing s p a c e w e a t h e r p r o d u c t s a n d s e r v i c e s i n Europe", Journal of Space Weather and Space Climate, V ol 4 (8pp), 2014. [3] PROBA2: https://proba2.sidc.be/ index.php , last visited: 15th March 2022. [4] S T C E N e w s l e t t e r : https:// www .stce.be/newsletter/ , last visited: 15th March 2022. [5] S T C E S h o p : https://www .stce.be/ shop/ , last visited: 15th March 2022. [6] JSWSC: https://www .swsc- journal.org/ , last visited: 15th March 2022. [7] K. Kauristie et al., Space W eather Services for Civil Aviation—Challenges and Solutions, Remote Sensing, 13 (18pp), 2021. [8] Ringing Sunspots: https://stce.be/ esww2019/ringingsunspots.php , last visited: 15th March 2022. [9] Google Jamboard: https:// support.google.com/jamboard/answer/ 7424836?hl=en , last visited: 15th March 2022. [10] Zoom: https://zoom.us/ , last visited: 15th March 2022. Page of 5 5 22 DOI: 10.5821/conference-9788419184405.004 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 1 of 5 D e s i g n a n d i m p l e m e n t a t i o n o f s p a c e e d u c a t i o n a l a c t i v i t i e s t o m o t i v a t e y o u n g s t u d e n t s i n C a t a l o n i a Guillem Olivel la 1 , Marcel Marin 2 __________________________________________________________________________ Abstract STEM education is a new interdisciplina ry concept t hat fuses the l earni ng ob jectives of sciences, technology, engineerin g and mathematics. A f ter concl uding t hat many under graduate students are not interested in STE M disciplines and taking into account t he admiration for space, a series of educational acti vities have been develope d to increase t heir engagement in this field. The propose d project-based workshops are diverse: desi gning and launchi ng High Altitude Balloo ns; buildi ng water rockets; protecting an egg from the impac t with the ground afte r being dropped from a drone; designing and buildi ng paper glide r s ; 3 D printing cus tomzied quad copters, etc. One of the most impress ive activities consisted o f desi gning, manufac turing and launching a low-cost high-altitude balloo n to take photog raphs of the s t ratosphe re. To do so, a kit was developed and vali dated: t his con tains a GPS t racker, a camera , an EPS b ox, a parachu te and a hel ium bal loon. The sel ection of the componen ts was done trying to mini mize the operational cost and maximizing the reliabili t y of the desi gn; the final High Altitude ba lloon weights 350g and has reached altitudes around 27.000 - 30 . 000 m. The educational act ivity is a 3 to 4 days workshop in which t he students go through t he process of buildi ng their own HAB, launching it and eventual ly recove ring i t to obtain t he photographs. The activiti es ha ve been implemented in multipl e schools and high school s in Cataloni a, and all of them have shown excellent results. After eval uating t he reasons why the workshops were well -received, it was conclud ed that s tudents were more implicated than in st andard lecture s because they went from a passive to an active mindse t. Moreover , the workshops were de signed to make them become curious and incr ease thei r eagerness to learn, while f orcing them to think and to tak e important decisions that ultimately in fluence the f inal result, rather than observing and admi ring somebody else’ s work. Keywords STEM , Space , Worksho p, HAB __________________________________________________________________________ 1 GoSTEM, Spa in, gostems pace@gma il.com 2 GoSTEM, Spa in 23 DOI: 10.5821/conference-9788419184405.005 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 2 of 5 Acronyms/Abbr eviations HAB High Altitude B alloon STEM Sciences, Tech nology, Eng ineering , and Math ematics UA V Unmanned A erial Veh icle 1. Introduction STEM education is a new interd isciplinary concept that fuses the learning objec tives of sciences, techno logy, engineering an d mathematics. It is a new way of learnin g, usu ally related to the project- based meth odology, which sti mulates interest and c reativity among students. ST EM careers ar e gro wing more a nd more as a demand of high- techno logical fut ure societies ( IoT, Smart Cit ies, 5G …) [1] . Th e problem lies in the f act that STEM studi es are usually not the priority among undergr aduate students and t his cou ld r esult in a decr ease in the l ife quality o f future societies [2] . Moreover, there is an important gend er gap when dea ling with STEM d isciplines: The maj ority of bachelor’s degrees are obtained by w omen; however, STEM subjects are no t attr active t o them [3 ] [4] . I ncreasin g th is i nterest in early phases of ed ucation such as high sc hool can reduce the gend er and soci al class gap [5 ]. On the other hand, in many c ountries, it is v ery common to divide the disciplines int o mathematics, technology, eng ineering an d sciences when k illing the c reativity among students and mak ing the learner lose generality whilst being close-minde d [6] . This can b e improved by apply ing a projec t-based methodology - to increase c reativity and interest - with a STEM framework. As can be seen, n ew ways of teac hing ne ed to be put on t he table in this new era : the l earning procedures need t o adapt to the new world. Most of th e progra ms an d activities that use space to motivate young stude nts to increase their interest in STEM disciplines use an admiration-b ased m ethodol ogy: They cons ist of showing examp les of bi g achievem ents of difficult cha llenges (outreach strategies of Rosetta mission a nd Ap ollo program) [7] . Usually, in this kin d of outreach strate g ies , the student does not have the opport unity to create anything. This is a logic al appro ach si nce access to sp ace is, in the ma j or ity o f c ases, expensive and technologica lly difficu lt. By doing so, most of the potential of s pace and its attractiveness to motivate h igh- school students to start STEM car eers is lost because t hey adopt a passive attitude rather than an active one. In order to so lve this short coming, a non -prof it or ganization call ed G oSTEM was creat ed. This is a project born in the I nternatio nal Space University t o motivate students from all over the world to pursue ST EM care ers. The go al of the organization i s to find an educational project for each interested schoo l, associat ion, or group of students co nsidering their needs and the ir desire to enter th e worl d of space and ST EM. 2. Workshops and activities Currently, sev eral work shops and proj ect -b ased activities are bei ng prop osed by GoSTEM . These are: 1. “High-Altitude B alloon: photographs from the stratosp here”. 2. “Saturn V: Fragi le launch” . 3. “Opportunity: Landin g in a n unknown planet”. 4. “Wright Brothers’ ch allenge ”. 5. “ 3D -printing y our own dro ne ”. All work shops are co mposed of the stag es depicted in F igure 1. Figure 1 . Workshops and activities architecture Follows a s mal l des cription of the ac tivities and workshops. Not e t hat all t he workshops h ave been designed to be done w ith several stud ents working s imultaneous ly. I n some cas es, the motivation and capabilities among them vary and th is m a y c ause difficu lties when tr ying to maintain a uniform flow when doing an activity . T o solve this pr ob lem, all the workshops described hereunder have different layers of complexity and guidance . This allows th e students to ad apt to dif ferent rhy thms an d to fee l comfortable wit hin the educ ational activ ity. 2.1. High- Altitude Balloo n: photograp hs from the stratosphere. This is, without any doubt, the most impressive activity do ne by GoSTEM. The educationa l workshop consists of a 3- 4 days project, whose ultimate goal is to take a ph otograph of the 24 DOI: 10.5821/conference-9788419184405.005 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 3 of 5 Earth, from the stratospher e as the one shown in Figure 2. Figure 2 . Photograph of the Earth at 36.000m altitude (Taken by GoSTEM). To do so, the students receive a kit designed by GoSTEM con taining the following it ems: A sports camera , tw o indep endent GP S Tracker s , all requ ired com ponents to do the platform f or the H igh-Altitu de B alloon, the p arachute , and the weather ba lloon with h elium [8]. Figure 3 . GoSTEM High Altitude Balloon kit 2.1.1. Camera To s elect the most appropriate camera for th e HAB, fi ve different properties were considered: weight, cost, image quality, temperatur e resistance, and battery duration. The final selection was a n Apeman A8 0, which h as an image resolution of 20 MP, a maximu m v isual angle of 170º, a minimu m self-timer shooting mode of 2s, and a ba tt ery that has proved a duration of 120m in @ -1 8ºC [9]. For th is com ponent, t he students have to do a trade-off between the batt ery duration in low temperatures, imag e quality , and the rate at which the photogra phs are taken. 2.1.2. GPS Trac ker For the trac king s ystem, 2 redu ndant devices are includ ed i n each kit. B oth trackers are GPS- based but differ on the way of tr ansmitting the ir position to the ground sta tion: A SPOT Trace is used to transmit the positi on of the HAB via satellite (Irid ium- based) [ 10]. A n Invox ia GPS does the same f unction but t ransmits i ts position via the SigFox network [11] . 2.1.3. Platform The Platform is co mposed of thre e d ifferent components: an EPS Box (internal dimensions 160 mm x 95 mm x 35 mm), cross - linked polyethylene f or the interior of the box , an d methyl methacrylate to cover the hole for the camera. The s tudents are in charg e of cutti ng, g lu ing , and prepar ing the platform to accommod ate al l other compo nents. 2.1.4. Parachu te The parachute is built from s cratch using ny lo n fabric. Th is is one of t h e most interest ing designs th at the students h ave to d evelop. Fro m a ba sic equation that represents the static equilibrium be tween wei ght an d drag, th e students h ave to derive the parachute diam eter from a give n H AB mass and drag coefficient. Moreover, they have to do a tr ade-off to s elect the termina l velocity o f th e HAB . If the term inal velocity is t oo high, the c ompone nts inside it su ch as the camera or GPS can brak e down. On the other hand, if the termin al velocity is too low, the H AB c an travel too much hor izontally during its descent and t his i ncreas es the probab ilities of landing in remo te areas. 2.1.5. Weather Balloon and He lium . After m any i terations, it w as concluded th at i s was high ly rec ommended to use an ov er- dimensioned weath er ba lloon. This allows the HAB to asc ent very quickly (which is favora ble given th e low battery durations in low stratospheric tem peratures ). Moreover, onl ine calcu lato rs s uch as the one presented by H ab hub [ 12], are used to predic t the flight o f the HA B . Since these on line tool s require inputs in t he form of pa rame ters that describe the HAB, stu dents are usu ally motivated to do test s a nd calculat ions to estimate properties such as the ascent and descent velocity . 2.2. Wright Brot hers’ challeng e This is on e of t he most c omplex activ ities proposed by GoSTEM. The challenge proposed to t he students consists o f des igning an d building a carboard airplane following all the design guidel ines of a real airplan e. The concep ts explained t o t he s tudents include static and dynam ic stability of an airpl ane, Lift, 25 DOI: 10.5821/conference-9788419184405.005 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 4 of 5 Drag, Ce nter of G ravity, etc . This is presented in a simpli fied way t hat allows the studen ts to understand the basic concepts withou t overwhelming t hem. After go ing throu gh s tructur al and d imensiona l tests, the a irplanes are thrown using a dedicated launc h pad. The structural tests consist of supporting t he airplanes by the ir w ingtips and hanging a m ass from the airplane center o f grav ity. Figure 4 . Wright’s Brothe r’s challenge 2.3. Satur n V: Fra gile launch & Opportunity: Landing in an unkn own pl anet These two activit ies a re very similar and share t he same arc hitectur e: a c hallenge is presented to the stude nts co nsisting of des igning, building, and testing a capsul e capa ble of protecting an egg agai nst its fall to th e groun d. For the f irst activity (Opportu nity: Landing in an unknown planet), th e capsule is la unched with a w ater rocket and, with the s econd one ( Saturn V: Fragile launch), t he c apsule is la unched with a quadcopter UA V or by o ther analog means. As a ll engi neering cha llenges, a set of re quirements constrai nts the design o f the students: • Maximum mass • Maximum quantity of toke ns used to buy materi als to c onstruct t he capsule. (Each student starts the activity with the same amo unt of t okens and t he non - complianc e of r equirem ents supposes the removal of t hem) • Design envelo pe This makes th e stud ents t o wor k with a cle ar objective and t he activ ity fo rces them to retrofit the design in ord er to meet the req uire ments. Figure 5 . Opportunity : caps ule launch from UAV. 2.4. 3D - printing your o wn drone The m ajority of ed ucational ac tivities c onsisting of building drones are limited to bui lding a pre - designed UAV. GoSTE M has proposed, for this activity, t he followin g: the students rec eive all electronics required to build a standard quadcopter , a s et of 4 motors, and a fl ight controller. The chal lenge consists o f designin g and 3D-prin ting t he fra me (platform) of th e quadcopter. The final dron e contains a camera to transmit r eal-t ime i mages and a w ifi-base d comms sys te m. Th e activity also de als wit h concepts suc h as stability vs maneuverab ility by pro posing different challenges to the s tude nts and making them adapt t he d esign for each sit uat io n. A n example of t his is how the students have to adapt a drone prepared for a n obstac le c ourse to a dro ne c apable of c ar rying a m ass. The driver of the first design is m aneuver ability , he nce, it has to be designed with short legs and low mass . The second on e , on the other ha nd, has to have lon g legs to max imize stability . The educationa l activity is c om pleme nted with simulators to prac tice how t o fly a qu adcopter. 3. Results and Discussions In total, 698 st u dents have part icipate d in different activit ies, distrib uted as f ollows: Table 1 . Results [1] Project Students M F “High- Al titude Balloon” 13 17 “Opportunity: landing in an …” 2 01 2 47 “Wright Brothers’ challenge” 49 32 “Saturn V: Fragile launch” 68 55 “3D-printing your own drone” 10 6 TOTAL 341 357 26 DOI: 10.5821/conference-9788419184405.005 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 5 of 5 In s ummary, all the activities we re a success : a ll the st udents ha d a great t ime deve loping their creations . As a rem inder, the main objective was to mo tivate young s tudents to engage i n STEM disc iplines by usi n g the a ttractivene ss of space. Their m otivation during the act ivities was obvious since the vas t m aj ority of them were extremely engage d during all the works hop s . This c ould dir ectly im ply a gr owth in the number of s tudents en gaged i n STEM care ers. After survey ing all the part icipants , they dec lared tha t they increas ed their c omprehe nsion of the STEM conce pts tre ated during t he ac tivity . Furthermore, they emp ha siz ed that the proposed wor kshops allow ed them to have a first-hand experienc e with the theoret ical concepts that the teachers explained to them i n class. In terms o f gen der equ ality, 51% of the participants we re female students an d no difference was apprec ia ted between the motivation an d perform ance between femal e and male stu dents. 4. Conclusions The educa tiona l proj ect has proved to be a n excellent platform t o fu lfill the objec t ive of popularizing STEM disc iplines. The next st eps woul d be to re ach more and more schools and ass ociations to con tinu e motivating yo ung stud ents to enga ge in STE M disciplines. As an example of t his, two me as ures have already been implement ed: 1. The creation of a website to pres ent the project an d spread it among all the schools in Cat alonia: www.go stemspace.com 2. The c reatio n of a summer c amp that en compass es all Go STEM workshops: www.spacecamp s.cat Acknowledgem ents The t eam wo uld like t o akn owledg e t he International S pace Un iversity and, in particular, Joan de Dalm au. We wou ld also like to t hank all the peop le that have co ntributed to the gr owth of GoST EM such as: Profes sor Gonglin Sun, Jordi Mazón a nd Marc B oada. References [1] StratoStar We bsite: www.stratostar.co m/intro - to -project- based , last vis ited: 15 th February 2022 [2] F. Aarrestad, et al. , S pace and STE M: one giant leap for educatio n, In ternationa l Space Univer s ity, 2012. [3 ] D. Beede, Wom en in STE M: A ge nder gap to innov ati on , Washing ton, DC: Economics and Statistics A dministration , 2011. [ 4] C. V. McDonal d, STEM Education: A Review of the C ontribution of the Disciplines of Science, Tec hnology, Engineering a nd Mathem atics , Science education interna tional , 27, 530- 56 9, 2016. [5] P. Boedeker, S. Nite, R. M. Capraro, M. M. Capraro , Women in ST EM: The impact of STEM PBL imple mentation o n performance, attrition, and course choice of women , IE EE Fro ntiers in Education Confere nce (FIE ) , El Paso, 2015. [6] R. Stichweh, D ifferentiati on of scientif ic disciplines: causes a nd con sequences , Encyclopedia of Life Support Sys tems , 2003. [7 ] ESA Outreach Reso urces : www.sci.esa. int/web/r osetta/- /53593- outreach-reso urces , last vis ited: 15 th February 2022 . [ 8] GoSTEM Web page: www.gostemspace .com , las t visited: 15 th February 2022 . [9] Apeman We bpage: www.es.apem ans.com , last visited: 1 5 th February 2022 . [10] SPOT Webpage: ww w.findmes pot.com , last visited: 1 5 th February 2 022. [11] Invoxia Webpa ge: www. inv oxia.com , last visited: 1 5 th February 2 022. [12] HabHub Websi te: www.predict.h abhub.org , la st visited: 15 th Februart 2022. 27 DOI: 10.5821/conference-9788419184405.005 4 th Sym p osi um on Sp ac e Ed uc at ion a l Ac ti vit i es Barcelona, April 20 22 Page 1 of 6 Missi on analysis of na nosat ellite constell ations with OpenSatKit Iván Sermanoukian Molina 1 , Lluís Montill a Rodríguez 2 , David González Diez 2 , Miquel Sureda Anfrès 2 , Jorge Mata Díaz 2 , Juan José Alins Delga do 2 __________________________________________________________________________ Abstract CubeSat r eliability is stil l considered an obstacle due t o the sizeable f ail rates generally attributed t o the dead - on - ar rival cases and early subsystem malfunct ions. Thus, as CubeSa t s' primar y pu r pose moves from technolog i cal demonstrations and university projects to missions where a significant risk of failure is not ac ceptabl e, an inexpensive method to emulate l ow E arth orbit constellations is being researc hed. The result s presented have been developed in the framework of the PLATH ON r e se ar c h project, which intends to develop a h a rdware - in - the - loop emulation platf orm f or nanosatellite constellations with optical inter - satellite communication and ground - to - sa tellit e link s. Consequently, a crucial aspect of this project is to have a sufficiently precise orbital propagator with real - time manoeuvring control and graphical r epresentation. NASA's O penSatKit , a multi -f a c et ed open - source platform with an inbuilt propagator known as 42, has been chosen t o analyse the programme's feasibility in order to create a constellatio n test ing bench. A s an initial development of a s oftware - in - the - loop appl ication, t he pre - processing of files has been automated; enhanced A tti tude D et ermination and C ontrol S y st em manoeuvres have been added and configured through bidi rectional socket interfaces , and th e results format has been modif ied to be easi ly post - processed with MATLAB and Simulin k. Keywords Constellations , Inte r - Process Communication, Na nosatellites, Orbit P r opagation __________________________________________________________________________ 1 Corres pon ding a uth or: Un iv ers itat Pol itècn ica d e Cat aluny a, Sp ai n , ivan.ser m anouk ian@u pc.edu 2 Univ ers it at Politèc nic a de Cata lunya, Spain 28 DOI: 10.5821/conference-9788419184405.006 4 th Sym p osi um on Sp ac e Ed uc at ion a l Ac ti vit i es Barcelona, April 20 22 Page 2 of 6 Acro nyms/Abbrev iations ACS Atti tud e Co ntrol System cFS core Fli ght Sy stem GNSS Globa l Naviga tion Sate llite Sys tem GS Ground Statio n GUI Graphic al Us er In terfac e HiTL Har dware in the Lo op IoT Interne t of T hi ngs IPC Inter - Proc ess Co mmunic ati on LEO Low Earth Or bit NASA Nati ona l Aeron aut ics and Spac e Admin istrati on NS3 Network Sim ulat or 3 PLATHON Integra ted H ardware i n the loop simulati on Platform o f Optic al commu nicat ions in Nan os atel lites SiTL Softw are in the L oop SSH Sec ure Shel l Pro tocol TLE T wo - Line Elemen t ECEF Ear th - centr ed, Ear th - f ixe d ECI Earth - centr ed inert ia l 1. Introduc tion Since th e be ginni ng of the spac e age, sate llit e desig n phi losop hy wa s dominat ed by conser vativ e des igns b uilt with highly r elia ble compon ents to e ndur e ext reme e nviron men tal condit ions . Durin g the las t t wo deca des, th e dawn of th e Cu be Sats has c hanged t his philosop hy , enab ling a whol e world of ne w possibi lities. The de ploy ment of m o nument al Cu be Sat const ellat ions in l ow E arth orbit (L EO ) is s et to revolut ionis e the s p ace s ector by en ablin g faster and mor e ec onom ical i nnovat ion c yc les. However , Cu beSat r elia bility is s till consid ere d an obs tacle due t o t he siz eabl e fa il rates amon g univers ities an d c ompani es, genera lly attr ibut ed to the d ead - on - arr iva l cas es and s ubsy stem malfunc tions [1]. In rec ent y ears , increas ed f light experi ence is c h anging this tren d, and future t estin g sy stems are s et to cons idera b ly reduce th e pro bab ility of an y malf unc tion . Mission Ana lys is is th e de sign a nd ana lys is o f satel lite orb its s uch th at the o bj ectives o f a space mis sio n are achiev ed in the bes t p oss ible way. Am ong t he main t ask s and outp uts , this resear ch has focus ed on gr ound s tat ion cover age, com mun icat ion a ngl es and d istances between s atellites , as w ell as ecl ipses and distance fr om the Su n, w hich are c rucia l to power s ubs ys tem manoe uv re st rateg ies. The res ults pres e nted i n t his paper h ave be en devel oped in the fra mew or k of the Int egr ated Hardwar e - in - the - loo p (HiTL) emul ation Pla tfor m of Opt ical C ommun icat ion s in Na nosat ellit es ( PLATHO N , from t he Spanis h ac rony m) . This r esear ch proj ect int ends to deve lop a Hardwar e - in - the - loop em u lation p latfor m for nanosa telli te cons tell ations with opt ical inter - satel lite com mun icati on an d grou nd - to - s at el lit e links . Section 2 s ummar is es the state o f th e art and program me select io n , sec tion 3 en um erates new pro gram me con trib utions duri ng all simulati on sta ges , s ectio n 4 shows the res ults of the new fe atures , and s ection 5 co nc ludes with th e c urre nt st ate of th e pr ojec t and pot ential improve me nts . 2. State of the art In ord er to pro pag ate or bi ts, t here are open - sourc e and pr ivate prog rammes that can perform t he s imu latio ns wi th a w ide r ange o f detail depen din g on th e pr oj ect requ ireme nts . Among the ava ilab le op en - sour ce op tio ns, t he Nationa l Aer onaut ics and Spac e Admin istrati on ' s ( NA SA) O pen Sat Kit has been chosen b ec ause it offer s H iTL c apab iliti es and can be easi ly cus tom ised to int eract w ith the projec t ' s models . Th us, as the progr amme is open - source, it is helpfu l for res earch an d devel opment purp oses , and in troduc es students and profes si ona ls to the s pace s ector . 2.1. O penSat Kit OpenS atKit is a multi - f aceted p latfor m that combi nes t hree indep end ent pr o gram mes [ 2] : Ball Aer ospac e Cor por ation ' s CO SMO S comma nd and c on trol pl at form for emb edd ed system s; NASA ' s core Flight Syst em (cFS), a platfor m and proj ect - i nd ependen t, re us able softwar e fr amew ork ; and NA SA ' s 42, a compreh ens ive, gener al - pu rpos e sim ulati on o f attitude an d traj ectory dy nam ics and cont ro l which can be ap plied to n umero us s pacecr aft compose d of mu ltipl e rigi d or flex ible b od ies [3]. Figure 1 . OpenSa tKit platform connectivity [4 ] This s tudy aims to analy s e the f eas ibil ity of NASA ' s 42 orb ita l propag at or in the PLATH ON projec t and its conn ectiv ity with Op enSat Kit modules . 29 DOI: 10.5821/conference-9788419184405.006 4 th Symposium on Space Educational Activities Barcelona, April 2022 geometric a nd radiometric correction techniques and image enhanceme nts. Finally, the image processing unit s h ows how to apply the different techniqu es to analyse the images visually and statistically. The last unit, applications of remote sensing images , shows the applications of remote sensing in different areas: forest, agriculture, oceans and water, ice , cartography, geology and land use . It is also the unit where students learn how to extract information from satellite data, applying indexes, classifications and algorithms to obtain Land Surface Temperature (LST) from thermal bands. In order to evalu ate t he co mpetences acquired by the students, they h ave to work on two different practical activities. Both of them t ry to emulate a real study ca se, and are designed to perform the following tasks: - Search and download images from a public catalog. - Apply an image correction p rocess over the images. - Create RGB band combinations. - Calculate indexes, such as NDVI, NDWI, NBR. - Apply cloud masks. - Create image mosaics. - Obtain LST from thermal bands. - Execute a supervised classification process . 2.2 The software The objective of a subject like this is to learn how to deal with remote sensing images and apply the correct methodologies in order to extract use fu l i n formation from them, but not how to use a specific software, library or toolbox. Nonetheless, it is obvious that students will perform the activities with a specific tool, and they need to be instructe d on that. Our f irst approac h is to let the students to choose their pr eferred tools, alth ough we offer some recommen dations and materials (lectures, tut orials, manuals a n d self-st udy activities) related to specific software. In that s ense, ou r priority is t o recommend the use of open-source tools. So, students are encouraged t o use tools like QGIS with the SCP plugi n, GRASS Gis and SNAP. With these tec hnologies, they can complete all t he mandatory activities, and we consider that are very u seful for acquiring the mandatory competences of the subject. For those students who choose other options, like ArcGis Pr o , E NVI, Erdas, etc., we don’t offer support materials, but if necessary we can give advice through the forums. 2.3 The data Nowadays there are lots of missions providing remote sensing images. It is in fact one of the main competences of the second unit of the course ( platforms, satellites and sensors) to be familiar with some of these missions and know their main characteristics in order to choose the best one for a specific project. As it would be completely impossible to design activities to work with data from a ll the available missions, we can select only some of them. Due to its impact on the industry, historical series a nd o pen access, Landsat data are widely used during the course. Students can easily obtain the images from Lan d sat catalogues using applications like Earth Explorer [1] or t hrough the SCP plugin. Also, Landsat data form a ts can be directly used by our recommended so ftware solutions and are offered in different processing lev e ls. Data f rom the Copernicus programme a re also used during the course, especially the images o ffered b y the Sentinel missions. In the same way as with Landsa t images, Sentinel d ata can be obtained for free throu gh applications like Sen tinel Open Access Hub [2] or also the SCP plugin. In t he cas e of Sentinel datasets, we mainly work with the images provided b y t he optical sensor on board S entinel 2. But we’ve also prepared a non-mand atory activity where students can p ractice with the ra d ar images provided by Sentinel 1. 2.4 EO4GEO Our experience dev elop ing projects in the geospatial sector is f undamental for desig ning a programme for a sub ject like this. We can Page 3 of 4 36 DOI: 10.5821/conference-9788419184405.007 4 th Symposium on Space Educational Activities Barcelona, April 2022 easily identify the skills that student must acquire in order to successfully join a team involved in the use and processing of remote sensing images. However, beyond the experience, there are some tools that ca n be very u seful in order to help in the design of such a pr o gramme. EO4GEO[3] is a co-funded project of t he Erasmus+ Programme of the European Union which aims to bridge the skills gap betwe en the supply and demand of education and training in the space/geospatial sect o rs. In the framework of EO4GEO, a set of tools based on the GIS&T body of knowledge [4] have been developed. For exampl e, the ‘ Bok Visualization and Search ’ [5] tool allows users t o navigate and visualize the EO4GEO BoK in a graphical a nd textual way. Starting from higher level concepts representing areas of knowledge in the field, one can browse down to more detailed concepts. So, this tool is specially indicated to identify the knowledge areas and concepts that the subject sho uld integrate. Figure 2. BoK Visualization and Search tool. The ‘BoK Visualization and Search’ t o ol is public, and no registration is required . The ‘ Curriculum De s ign Tool ’ [6] (CDT) allows u sers to create, edit and find educational offers in the field of Earth Observation and Geograp hic Information. The tool could be useful to define the remote sensing subject p rogramme re-using descriptions of related BoK concepts and link specific EO/GI BoK concepts and skills. 3. Conclusions Remote sensing is a very valuable source of information fo r GIS projects. So, from our point of view, a master’s degree in GIS must include a course about remote sensing. A s u bject li ke this should guar an tee t h at students have learnt the basic principles of remote sensin g, and have also acquire d competences in order to search and download remote sensing images, perform enhancements and corrections over them, and also extract information b y applyin g some processes like RGB band co mbinations, index calculations, band maths or classifications. Open-source tools like QGIS and the S CP plugin, GRASS or SNAP are g ood candidates to use during the course. Despite t he wide va riety of providers, the open catalogues form Landsat and Sentinel are very useful for acquiring the skill s of the course. Finally, the GIS&T BoK and tools developed in the framew o rk of projects like EO4GEO can help in the design of the cours e topics. References [1] E arth Explorer Website: https://earthexplor er.usgs.gov/ , last visited: 25 th February 2022. [2] O pen Access Hub Website: https://scihub.copernicus. eu/ , last visited: 25 th February 2022. [3] E O4GEO: http://www.eo4geo.eu/about- eo4geo/ , last visited: 7 th March 2022. [4] G IS&T Body of Knowledge: http://www.gi-n2k.eu/wp-conte n t/uploads /2014/01/UCGIS_GISandT _BoK_DigReI ssue2012.pdf [5] B oK Visualization and Search: http://www.eo4geo.eu/to ols/bok- visualization-and-search/ , last visited: 7 th March 2022. [6] Curr iculum Design Tool: http://www.eo4geo.eu/to ols/curriculum- design-tool/ , last visited: 7 th March 2022. Page 4 of 4 37 DOI: 10.5821/conference-9788419184405.007 4 th Sy m posiu m on S pace Educational A ct ivities Barcelona , Ap r il 2022 Page 1 of 5 C ANSA T C o mp etiti o n 20 20: B es t te ch ni cal dev elo pmen t b y O r bi S at t eam Dav id H er nand o - Diaz 1 _ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ _____ ___ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ _ Ab str act Or biSa t is a high sc ho ol educ at ion al proj ec t t hat w as par t o f t he CA NS AT S P AI N 2 02 0 s tu de nt com pet iti on or gani z ed by ES ER O. T his pr ojec t has r anke d fi r st in t h e Cat alo nia C h ampio nshi p an d sec on d at t he Na ti onal Ch ampi ons hi p, wi nnin g th e pri ze f or t he bes t tec hni c al dev elop m ent. Or bi Sat has s ucc es sf ull y ful fil le d t he objec ti ve of c rea ting a mi ni sat ell it e wit h the si ze o f a s od a c an th at w as l ater lau nch e d by a r oc ket of the C O SMIC R ese arc h U PC S tu dent s Ass oci ati on t o anal yze p hysi c al as pe cts of th e ai r suc h as pr es sure , t e m p erat ure, h u m idi ty , or t h e am ou nt of U V so l a r radi atio n of a t err itor y. Tha nks to t he Ca nS at pres ent ed by thi s te am, d uri ng t h e la unc h w e wer e abl e t o kn ow t he pr ese nce o f up t o 15 ch emic al ele ment s i n t he ai r. El em en ts ra ngi ng fr o m hy dr o gen an d oxy gen c an i ndi ca te w ater in th e at mos p her e or oth er gr een ho use gas es s uch as C O2 or m et ha ne . The l aunc h ed r ock et r eac hed a n ap pr oxi mat e hei ght of 5 32. 7 ± 1. 5 me ter s, w it h t he se nsors we w ere able to det ermi ne th e apo ge e of t he r ocket an d t he s ubs eq uent r el eas e o f th e mini s atell it e an d de ploy m ent of the par ach ute . W e w er e als o a bl e t o i nter rel at e t he al ti tu de dat a wi th p ar ame ters s uc h as hu midi ty, UV r adi a ti on, pr es en ce of hydr og en , am on g oth er s. The C anS at pr ese nt ed by th e Or bi Sa t te a m h ad a uni qu e d esig n n ever s ee n befor e in o th er CanS at c om pet iti ons , s ol vi ng probl e ms suc h as hi gh w eig ht a nd ov erh e ati ng. T his desi gn ma de by Aut oC AD w as an op en co nc ept w her e the ai r ca n r efr iger at e t he CPU an d also th e 3D pr int ed c onc ept s ave d 1 25 gr a m s ov er a thir d of the maxi mu m all owe d. In addi tio n, al l t he dat a c oll ect ed w as broa dca st i n r eal - ti me and r ecei ved by a gr ound s t ati on ev er y 0 .2 5 sec on ds. Bef ore t he l au nch, a si mul ati on w as c om plet ed es tima tin g a 6 1 se co nds fl i ght , fin al ly , th e re al fl ight was 5 9 s ec onds . Th e v ast m ajor it y o f t he pr ojec t wa s done d uri ng t he COV ID - 1 9 pa ndemi c , th e c ons eq uenc e w as new meth o dolo gies t o c ar ry on th e pr oj ect w it h a mi ni mum ti m e for t he w or ksh op an d t est p ha se t ha t w ere sup pli ed wit h s i mula ti ons h avin g a bet ter per f orm anc e tha n exp ect ed. Keyw ords CanS at , E duc atio nal Pr oje ct , ESER O _ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ _____ ___ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ _ 1 Univers it at Polit èc nica de Cat alunya ( UPC), S pain, david.her nando. diaz@ es t udiant at. upc . edu 38 DOI: 10.5821/conference-9788419184405.008 4 th Sy m posiu m on S pace Educational A ct ivities Barcelona , Ap r il 2022 Page 2 of 5 1. Intr od uc tio n CanSat is an initiat ive of t he E uropean S pace Agency [1] that challenges s t udent s from all over E urope t o build and launc h a mini s a t ellit e the s ize of a " soda c an" to a height of no m ore than one k ilomet er . T he challenge f or part icipant s is t o fit all t he m aj or subsy stems found in a s at ellit e: elect ric power, sensors , and the c omm unicat ions sy st em. Ev erything m ust fit into t he v olume and s hape of a s oda can. Subsequent ly , t he CanSat will be launched, in our cas e by a roc ket , t o a height of no more than one kilomet er . Alt hough on ot her occas ions, it is dropped f rom a plat f orm , a drone, or a balloon. Onc e t he CanSat parac hut e [ 2 ][ 3] deploys, t he miss ion begins, and t he s at ellit e st art s to perf orm sc ient if ic experiment s as it descends and lands saf ely . After t he f light , t he t eam s mus t pro cess the dat a and draw conclus ions about the f light . The ex perim ent s that t he CanS at will perf orm while descending ar e divided int o t wo par t s fir st ly , t he Prim ary Miss ion, m andat ory f or all team s and c onsis t ing of t he c onst ant emis sion fr om t he s at ellit e and recept ion f r om a gr ound st at ion [4][5 ] of t emper a tur e and at mos pheric press ure dat a at leas t once per s econd. The S econdar y Mission is fr ee and is the one that dif f er ent iates CanSat fr om the o ther t eams. However, t he im plement at ion of bot h in a diff er ent way led t he O rbiS at t eam t o win t he tec hnical ac hievem ent f or the com plexit y and original it y of t he design, implem ent at ion, and integr at ion. In t he c ase of the Or biSat team, the Pr imar y Miss ion ment ioned abov e communicat ed wit h the gr ound st at ion f our tim es per se cond, allowin g us t hat if one of t he temper at ures and atm ospher ic pr ess ure dat a did not arrive or arr ived damaged, it could be discarded wit hout aff ec t ing t he ov erall r esult s. We als o decided t o ext end it a lit t le more by obtaining t he humidit y data and s ending t he s at ellit e's GPS posit ion thr ough t he ant enna, which helpe d t o loc at e it once it had f allen. The O r biSat team' s secondary mis sion was t o recr eat e a kind of pr obe sat ellit e t hat would be launched on a pl anet ar y m iss ion. A s it descended t hr ough t he at mos phere, it would collect dat a on gas es t hat m ight be in t he atm ospher e of t he hy pot het ical planet . It als o collect ed inf or mat ion on UV r adiat ion, and all were st or ed on t wo SD c ards that ser ved as a backup if one was damaged dur ing t he impac t. 2. Prototy p e 2 . 1. Vers io n 1 The CanS at st r ucture pr esent ed here s hows an open concept t hat has been ent irely designed in Aut oCAD, allowing us t o save m any r esour ces since we wer e able t o perf or m t es ts and simulat ions of prac t ical s pace for the placement of t he various ex perim ent s without the need for fur t her pr int ing. 2.1.1. M ater ial s The m at erial us ed f or the str ucture was Polylac t ic A cid, com monly known by its abbreviat ion ( PLA ). T he pr opert ies of PLA [6] are int eres t ing; t he one we highlight is it s melt ing t emper at ure as it is relat iv ely low, be tween 130 - 180 ºC mak ing it an ideal mat erial f or 3D print ing. I n addition t o the proper ties t hat this plast ic has tha t perfec t ly adapt t o our needs, it is a plas t ic obtained f rom fer ment ed v eget able st ar ch. In other wor ds, it is a plast ic t hat does not c ome from petr oleum. 2.1.2. P ro tot yp e parts This prot ot y pe CanS at (Figure 1) , was divided into t hr ee part s. The lower par t was where the batt er y and two S D car ds would be housed. The middle par t, a c irc ular piec e 3 millim eter s thick , serv ed as t he lid of t he lower part and t he bas e of t he upper part . Finally, t he upper par t was t he st ruc t ure that would house all t he s ensors , the Arduino UNO boar d, and t he G P S antenna. The lower part (Figur e 2) has t hr ee pr ot ect ed areas; t he f ir st two on the s t arboar d and port side of the CanS at are symmet ric al and one mor e in t he aft ar ea. I n addit ion t o pr ot ect ing batt er ies and S D mem ory cards , t his is t he place where t his part connect s to the r est of t he CanSat 's part s . The upper part has three columns loc at ed at 120º and whose t hick ness is 10. 6 m illimet ers . Thes e colum ns allow having an inter ior s pace where all t he sens ors were loc at ed. Mor eover, we would find a nother cir cular cov er at t ached t o the c olumns in t he upper part . T his c over has two holes , t he f irs t and centr al one where t he eyebolt t hat would j oin t he parac hut e wit h t he CanSat would be locat ed. T he s econd hole was used t o pass t he cables from t he lower part to the upper part . The piec es of this f ir st CanSat pr o t ot ype wer e j oined wit h polym er glue. 39 DOI: 10.5821/conference-9788419184405.008 4 th Sy m posiu m on S pace Educational A ct ivities Barcelona , Ap r il 2022 Page 3 of 5 Figur e 1 . CanS at Pr o t otype V er si o n 1. Figur e 2 . L ower part sect i on CanSat P r ot ot y p e Version 1 . 2.1.3. 3D P r int i ng The 3D print ing was carr ied out , leaving a square m esh ins ide t he st r uct ur e, whic h allowed saving weight , c ount ing both the mesh and the outer layer , which was solid. A s a res ult , we only used 30% of t he material c ompar ed t o mak ing the whole f igur e solid. 2 . 2. Ver s io n 2 We did not hav e t he opport unit y to pr int t his second pr ot ot ype, alt hough it would hav e allowed us t o cor rec t err ors t hat we had detec t ed af t er submitting t he first prot ot y pe t o some tests. 2.2.1. M ater ial s The m a ter ials us ed were the s ame as t he first prot ot ype : P LA plastic and polym eric glue. 2.2.2. Pr otot yp e part s This sec ond prot ot ype (F igure 3 ) had two pieces, t he f ir st lower par t f ormed by t he lower part ment ioned abov e and t he cir cular piece that ac t ed as a lid. The s econd part was very similar t o t he upper par t ment ioned bef ore. The lower part ( Figur e 4 ) in t his prot otype was going to be t he s um of t he lower par t of the f irst prot ot ype and t he int er mediat e part , and it also includes t hr ee holes wher e t he upper part would fit . It also c ont ains f our holes t hat have the sole purpose of being places t o pass cables f rom the lower part t o the upper par t o f t he o ther way around. Unlike t he pr evious prot ot ype, the rear area is c over ed, allowin g acc ess t o t he inter ior area only t hr ough t he f r ont part prot ecting mor e component s . The upper area would be very similar to the one ment ioned in t he f irs t pro tot y pe. The m ain changes would be s ome bar s in t he lower area of t he three c olumns that would be inser t ed in the ot her piece of t his prot ot ype. I n addit ion, we implem ented c hanges t o r educe the widt h of t he columns and round of f their inner edges. It would also include f our holes in the upper part to allow dif f er ent accesses, t hus reduc ing the number of c ables needed. Figur e 3 . CanS at Pr o t otype V er si o n 2. 40 DOI: 10.5821/conference-9788419184405.008 4 th Sy m posiu m on S pace Educational A ct ivities Barcelona , Ap r il 2022 Page 4 of 5 Figur e 4 . Low er part s ection CanSat P r ot ot y p e Version 2 . 2.2.3. 3D P r int i ng The 3D pr int ing would have been carried o ut following t he m et hod prev iously m ent ioned in the f ir st protot ype, alt hough slight c hanges would have. T he lower and u pper part s would have a dif f erent m esh at this prot otype . T h e lower par t would hav e been print ed wit h a mesh of 90%, while t he upper part would have a m e s h of 45%. As a r esult, in addit ion t o incr easing t he weight , we would not hav e h ad t o ins ert ballast , t hus occupy ing spac e, which would hav e allowed us to lower the c ent er of gravit y, thus improving st abilit y dur ing t he des cent . I n addit ion, t he CanSat would be posit ioned in t he opt imal way to open t he par achut e in a s horter time. 3. R esul t s an d disc uss io n The P rim ary Miss ion t hat the OrbiS at team planned worked per f ect ly , fulf illing all t he requir ement s r equest ed by ESE R O Spain. T he maxim um height t hat the r ock e t r eached was 532.7 ± 1. 5 meters , which was lat er c heck ed corr ect ly by the organiz at ion. In t he height gr aph ( Figure 5 ) , it is poss ible t o observ e t wo peaks after the max imum point of the gr aph. T he r ock e t itself creat ed t he f ir st one when the war head deploy m ent. T he rocket made a sm all char ge explode t o deploy t he warhead, and sinc e t he sat ellit e was s t ill ins ide the r ock et, it c ould det ect t hat press ure spike. The par achut e' s opening caused t he s econd one since it t ook 2 sec onds to open fr om being fully f ol ded. Figur e 5 . H ei g ht gr a p h O r bi S a t launch July 20 20. On the ot her hand, the S econdar y Mission was not s o brilliant s ince we had the f ailure of t he CO2 s ensor , and even hav ing chec ked its corr ect oper at ion t he day bef ore, it gav e complet ely err oneous and meaningless dat a. Ther ef ore, af t er analyzing t he s ensor data, we had no choice but t o dismiss i t and not tak e its infor mat ion as relev ant . The r est of the s ensor s of t he S econdar y Miss ion work ed perf ec t ly and wit hout problem s. As we had predict ed, the str ucture ended up yielding at t he weakes t point . O n c e t h e compet it ion was over and analyzing t he debr is, we could see t hat becaus e we had t o load ballast t he day bef or e t he launch and that t his ballast exc eeded t he a llowed dim ensions , we had to br eak a j oint. Unf or tunat ely, when we reass embled t hat j oint, we did not c lean well t he surf ac e of t he old adhes ive, and we added new adhesive on t op of it , creating t iny air chamber s as we f eared t hat r esult ed in t he break age of t he lower par t of the CanSat . As we thought that a slight possibilit y of break could occ ur at t he lower part of the CanSat , we att ac hed t he bat t ery t o the main body of t he CanSat . If the situat ion of that breakage occur red, t he operation of t he s at ellit e would not be compr omis ed, and it could c ontinue operat ing wit hout problem s. So t hat cont ingency plan work ed perf ec t ly. CanSat regulat ions requir e a m inimum weight of 300 gr ams , but thanks t o t he 3D pr int ing used and the des ign, our c asing had s uch a low mass that we init ially lack ed 12 5 gram s. T his problem would have been solv ed wit h t he s econd vers ion. However , in a c ase closer to t he r ealit y of launc hing a sat ellit e int o or bit, ev ery gram saved is money . 41 DOI: 10.5821/conference-9788419184405.008 4 th Sy m posiu m on S pace Educational A ct ivities Barcelona , Ap r il 2022 Page 5 of 5 4. Conc l usi ons Af t er the v arious argum ents expos ed previous ly, we c onclude t hat t he fir st design we made was out s t anding sinc e it demonst r ated its capabilit ies in t he c ompet it ion t o achiev e t he second pos it ion. Mor eover , it was a fir st t est prot ot ype of s ever al t hat wer e expec t ed t o be manuf act ur ed but t he pandemic f or ced t o modif y t he plans wit h little t im e t o act. The s econd pr ot oty pe would have s olved t he biggest problem we had dur ing the c ompet it ion, the br eakage of part of our CanSat. However , it would have also helped t o im prov e t he aest het ics and pos sibly would have allowed us to be in t he firs t posit ion. The open c oncept des ign avo ided many problem s and gave us many options in the days befor e t he f inal. F or exam ple, after having som e sever e f ailures in t he cont rol boar ds, it allowed us t o int roduc e an Ar duino Uno board in t he CanSat , som et hing t hat other t eam s did not underst a nd how t o f it. Consequent ly, it has advant ages when t r ansf er ring it t o ot her t y pes of s econdar y missions other t han our s. Also, this design has allowed us to hav e more accur at e dat a, espec ially in t emper at ure, s ince no heat pr oduced by t he CPU and gas s ens or s alter t he meas ures . Ackno wl edg emen t s I would lik e to thank the S ant o A ngel sc hool f or their suppor t and spons ors hip t hrougho ut t he proj ec t . I would also like to thank the City Council of G avà f or sponsor ing the nat ional launch cam paign in G ranada a nd the whole ESE RO S pain t eam f or organiz ing t he CanSat Spain 2020 com pet it ion wit h all t he diff ic ult ies it entailed due t o t he pandem ic. Referen ces [1] E SERO. ES 2020 GE TTIN G STAR TE D WIT H CANS AT : htt ps: //es ero. es / wp - cont ent / uploads/ 2019/ 10/ T 08_G et t ing_S tar t ed_wit h_CanSat . pdf , last vis it ed: 5 th Febr uary 202 0. [2 ] FRUITY C HUTE S PROF ESSIONAL AEROSP ACE RECO VERY SOL UT IONS : htt ps :// fruit y chut es.com / help_f or_par ach utes / parac hut e - help/how_t o_m ake_a_p arachut e. ht m , last vis it ed: 5 th July 202 0. [3 ] ESE RO.E S 2020 DESIG N Y O UR PARA CHUT E : h ttps ://es ero .es/w p - cont ent / uploads/ 2019/ 10/ T 10_Par achut e _Design. pdf , las t visit ed: 5 th Ju ly 202 0. [4] ESE RO.E S 2020 C OMMUN IC ATIN G WIT H RADIO : http s ://e se ro .e s/wp - cont ent / uploads/ 2019/ 10/ T 11_Radio_Co mm unicat ion. pdf , las t visit ed: 15 th June 202 0. [5] ESE RO.E S 2020 MEET ARDUI NO : htt ps :// es ero. es/wp - cont ent / uploads/ 2019/ 10/ T 04. 1_Meet _A rduino_C. pdf , last vis it ed: 20 th Januar y 202 0. [6] J. Lunt, Lar ge - sc ale produc t ion, proper ties and com mer cial applic at ions of poly lact ic acid polymers , Poly mer Degradat ion and St abilit y , 59, 1, 145 - 152 , 1998 . 42 DOI: 10.5821/conference-9788419184405.008 4 th Sym posium on Spa c e Educational Activities Barcelona, April 2022 Page 1 of 5 T O L O S A T p r o j e c t : G r a v i m e t r y a n d C o m m u n i c a t i o n Knigh t Trista n 1 , Rou sse Axel 2 , Allietta Clémen ce 3 , Bérat Benja min 4 ___ _____ _____ _____ _____ __ _____ ___ ______ ____ ___ _____ _____ ____ ___ __ ____ _____ Abs tract The use of Constellatio ns fo r weather scienc e, security and disaster mo nitor ing is a major ch alleng e for space application services. Satellite to sate lli te com munication using existing constellatio ns has not been exte n sively explored yet. It ca n improve t h e communication ti mes fo r sm all -satellite missions which have limited access to gro und sta tions. T hu s, a m ission to demonstrate th e fea sibility of th is link is requir ed. Another elemen t of interest in space application is Ear th Ob servation, espe ci ally in t he co nte x t of Clima te Change. Gr avimetry allows an understanding of mass transport in the Earth System t hr ough the r em ote sensing of the time variation of the Earth gravity field. Cub eSats ar e low - cost small- scale and hen ce lower risk solutions to Earth Obser vation m is sion s. University CubeSats ha ve shown th eir success in demon st ration and scientific m issions, and ha ve a great potential in pr ovidin g students with pra ctice and application o n real space syste m s. In th is conte xt, th e stu dent association s ASTR E and SUPAERO Cub eSat Club h ave joined in a Cube Sat progr am called TOLOSA T , with the hope of demonstrating such technologies. Gathering 70 stu dents from T oulouse, the team was split into subsystems in acco r dance with th e concurrent engineer ing principles. The work performed follow ed rec omme ndations fr om exp erts from the Frenc h National Centre f or Space Studies (CNES) and the ind ustry. The TOLOSAT payl oads have to te st an d dem onstr ate new mea ns o f measurin g gravity and add ressing commu nication issu es. Firstl y, for the gravimetry mission, ou r approach relies solely o n GNSS to compute the g r avity field, a voiding e xpensive gravim eters. For the communication mission: the Ir idium constellation will be used as a n int er mediate b etween t he CubeSat a nd t he g r ound sta tion. O ff-th e-shelf compon ents such as patch antennas a re p lanned to pr ove their efficiency in orbit. T his would imp rove the coverage a nd the c om munication window. The pr eliminary design was c om pleted. TOLOSA T was de si gn ed as a 3-unit nanosatellite, on a 97.4° inclined, 500km high orbit. Ma rg ins wer e a lso en sured to allow a third pa yload to be de fined in the future, that will be use d for fi n ance and partnerships. Detailed designs are still required, b ut the ed uc ational pur p oses hav e bee n fulfilled, in t er ms of discover y of the d evelopment of spac e m issio ns as well as in th e tea m work cultu re. T he te am is now mo ving on to a n ew phase, dedicated to a more detailed co nception with an on -going focu s on th e intr o duction to students to technical - but not only - fields of k no wledge applied to space systems. Keywords Gravime try, I ridium, Students ___ _____ _____ _____ _____ __ _____ ___ ______ ____ ___ _____ _____ ____ ___ __ ____ ___ 1 Knight Tr istan: Univesité Paul Sabatier, Fra nce, [email protected] m 2 Rousse Axel : ISAE-SUPA E RO , F rance 3 Allietta Clémence: ENAC, France 4 Bérat Benjam in: ENSE EIHT, France 43 DOI: 10.5821/conference-9788419184405.009 4 th Sym posium on Spa c e Educational Activities Barcelona, April 2022 Page 2 of 5 1. Introduct ion This pape r goes in de tail over the TOLOSAT student pr oject and its current state as of Marc h 2022. Section 2 details all ma in aspects o f the syste m ranging f rom technical to fi nancial progress. It i s importa nt to not e that the p r oject is se parate d into subsystem teams which each f o cus on o ne aspect o r system of the project. In subsectio n 2.1 the two payload t eams f o r Gravimetry an d Iridium e x p lain th eir me thodological approac h and expected r esults. T he systems and mission analysis te am’s role are cove red in subsec ti on 2.2 , and subsection 2.3 separ ates the sp ace segmen t in the wor k carried out by ea ch of th e six te chnical teams. Finally, the financ e a nd partn ership aspect of the m ission is addre ss ed by subsectio n 2.4 . 2. Result s, progress and discussion TOLOSAT students achieved the preliminar y design. Our satellite was designed as a 3 unit nanosate llite, on a 97.4° inclined, 50 0k m high orbit. Margins we r e also e nsured to allow a possible thir d payload to be defined in the future . 2.1. TOLOSAT pa yloads The TOLOSAT payload s have to test a nd demon st rate new m ea ns of measuring g r avity and ad dressing communic a tion issues. 2.1.1. Gravim etry payload Our gravimetry mission relies solely on GNSS to com pute th e gravity field and dr aw a ge oid (Figu re 1.) (while satellites typically de du ce the gravity field fr om their orbit using com plex an d expensive o n -b oard g ravimeters c oupled with GNSS data [3]). Figure 1. Earth's ge oid as seen by European satell ite GOCE (credit ESA) [1] This does not requ ire h eavy e quipment and was selected for t h e mission. T his method was fir stly describe d in detail b y Ales Bezdek and al. [1 ]. Their work highlights th at m apping the g r avity field could be done without heavy a nd costly equipm ent, that is why we have based o u r studies on their r esearch. Here is a brief sum mary of the a cceleratio n - based method: The calcula tions are based on the fa ct that the geoïd is a n eq ui p otential. Thus , on e has to solv e a Laplace equation, E q . 1: 𝛥 𝑉 = 𝜕 2 𝑉 𝜕𝑥 2 + 𝜕 2 𝑉 𝜕𝑦 2 + 𝜕 2 𝑉 𝜕𝑧 2 ( 1) It could be demonstrated th at the solution of thi s equation is of the following form, whic h introdu ce Legendre p olynom and Stokes coefficients, in Eq. 2 : 𝑉 (𝜃, 𝜆 , 𝑟 ) = 𝐺𝑀 𝑟 ∑ ( 𝑅 𝑟 ) 𝑛 ∑ [ 𝐶 𝑛𝑚 𝑐𝑜𝑠 ( 𝑚𝜆 ) + 𝑛 𝑚= 0 ∞ 𝑛 =0 𝑆 𝑛𝑚 𝑠𝑖𝑛 ( 𝑚𝜆 ) ] . 𝑃 𝑛𝑚 ( 𝑐𝑜𝑠𝜃 ) ( 2 ) This eq uation can be simplify in Eq. 3 : 𝑉 (𝜃, 𝜆 , 𝑟 ) = ∑ [ 𝐶 𝑛𝑚 𝑉 (𝑐) (𝜃 , 𝜆, 𝑟 ) + 𝑛 ,𝑚 𝑆 𝑛𝑚 𝑉 (𝑠) (𝜃, 𝜆 , 𝑟 )] (3) This solution is a development in spherical harm onics. Thanks to the four main GNSS constellations (GPS, GLONASS, GALIL EO an d BEIDOU) the latitude, longitude and altitude of the satellite in the Ear t h Center Ea rth Fixe (ECEF) fr ame ar e known. After convert ing th e position in the East North Up (ENU) frame , th e position became 𝜌 (𝑟, 𝜃, 𝜆 ) , where the param eters are respectively the altitude, latitude a nd longitud e of the satellite. Then , its a ccel e ration c an be computed by a numer ical d erivation thanks to a Golay filter. The acceler ation is decomposed in a s um of contribu tions, in Eq. 4: 𝑑 2 𝜌 𝑑𝑡 2 = 𝑎 𝑔𝑟𝑎𝑣 + 𝑎 𝐿𝑆 + 𝑎 𝑡𝑖𝑑𝑒 + 𝑎 𝑁𝐺 + 𝑎 𝑅𝐸𝐿 = 𝑎 𝑔𝑟𝑎𝑣 + 𝑎 𝑜𝑡 ℎ 𝑒𝑟 (4) With: ● 𝑎 𝐿𝑆 and 𝑎 𝑡𝑖 𝑑𝑒 the acceleration due to lunisolar p erturbations a nd tides ● 𝑎 𝑁𝐺 and 𝑎 𝑅𝐸𝐿 the acce le ration due to relativity an d non g r avitational forces 44 DOI: 10.5821/conference-9788419184405.009 4 th Sym posium on Spa c e Educational Activities Barcelona, April 2022 Page 3 of 5 By applying t h e th i rd Newt on’s law, thi s accelera tion ca n be linke d to the g radient of t he potentia l which is g iven by applying the na bla opera tor to Eq. 3 . Eq. 5 : 𝑎 𝑔𝑟𝑎𝑣 ( 𝜌 ) = 𝛻𝑉 (𝜌 ) = ∑ [𝐶 𝑛𝑚 𝛻 𝑉 ( 𝑐 ) ( 𝜌) + 𝑛 ,𝑚 𝑆 𝑛𝑚 𝛻 𝑉 (𝑐) ( 𝜌)] (5) Then , the only things which rema i n u nknow n are th e S to kes coeff icie n ts 𝐶 𝑛𝑚 and 𝑆 𝑛𝑚 . The se coefficients can be determine d by a pp lying t he least squa re met hods to this last equation. Then , all th e terms of the spherical harmonic developm ent in Eq. 2 are known and one has access to th e local gr a vity potential. 2.1.2. Iridium payload Nowadays com m unications with sa te llites are enabled by ground stations and limited by th e rare p asses of a sa tellite over a n accessibl e groun d station. The TOLOSAT m ission pr oposes a different type of p rotocol: exploit an e xisti ng telecomm unication constellation (namel y Iridium Next) in order to make a relay betwee n the g round and the sat e llite. T his add ition al passage ma y enable com munication with the groun d much m ore frequently: there are inde ed up to 66 Iridium satellites an d multiple Ir idium groun d stations. Several aspects make the Ir idium mission tricky. First, the Iridium satellites’ bea ms take th e for m of visibility cones th at are de signed so that th e Earth’s surfa ce is entir ely covered (Figure 2.) Figure 2. Cover a ge of Iridium Next Constellation on ground [ 2] As the a ltitude rises, th e cove rage ensured by the cones decreases, which fixes an important constra int for our 50 0 km high satellite: ● The s atellite must be in the visibility cones. Second, th e existen ce of th e Doppler effe ct furthe r reduces the total time visibility of o ur nanosate llite. The Iridium antennas are inde ed sensitive to the Dopple r f requency shift. T he modem algo rithms hence imposed an add itio nal requir ement: ● The frequency shift caused by the Doppler eff e ct should be lim it e d to +/- 37.5 kHz. According to certain s ou rces (includin g specialists from aerospace industry), the time derivative of the Dop pler ef fect (the Doppler rate) would also affect the commu nication. Thi s has to be pr oven and backed by precise valu es. These two con straints set a limit a ltitude o f 650km and a m i n imum elev ation angle o f 2 4° for o ur satellite. Fo r a 6 hours covera ge simulation, we obtained the followin g estimation s of Tabl e 1: Tab le 1. Table w ith visibility res u l ts for a 6 hours cover age simulation [ 1] Mean time session Nb o f session s To ta l t i me visibility Onl y visibility 104s 31 214 m in Wi t h Doppler ran ge 51,6s 39 134 m in Wi t h Doppler ran ge and delta Doppler 63,5s 8 8 m in When it comes to hardware ch oices, th e Iridiu m subsystem selected a L- band antenn a (1621 MHz) which has been subject to a lin k budget, and an Iridium mo dem which is in te ste d and o perated tha nks to a PCB ( Printer Ci rcuit Board) and driver software the su bsystem develope d. 2.2. Systems & mission an alysis The System engin e ering subsystem is in ch arg e of crea ting and managing the co mple x architecture of the TOLOSAT project, seen as a whole system including the nanosatellite, th e groun d segme nt and the launcher. This wor k requires the collection of data amon g all subsystem s. The data is then formatted an d well-structured th rough the Valispace br owser, making sur e there are no wrong assumption s 45 DOI: 10.5821/conference-9788419184405.009 4 th Symposium on Space Educational Activ ities Barcelona, April 20 22 Page 5 of 6 Figure 6 . Vertical (top) and Horizontal (botto m) errors obt ained with (blue) an d without ( red) Klobuchar model . Figure 6 depic ts the ef fec t of cor rectl y modell in g the io nosph eric del ay on th e user c o ordinat es . For th is p urpos e, the proc e ss is exec uted t wice. In the fir st run ( w hos e res ults are depic ted in blue c olour) , we appl y t he full S PS m odell ing, with al l ter ms of Eq.1 inc luded . In the s econd run (dep icted in red c olo ur) , we intent ion all y disconn ect the ionos pher ic m odel, mainta inin g all oth er proc ess ing opt ions f rom the SPS unchan ged. W e can obs er ve tha t t he vertic al c om ponent of the error is degr aded b y a f actor three when t he ionos pher ic de la y is not c or rec ted. As it ca n be seen, th e ver tica l pos ition error is link ed to the ionos pher ic de la y mode lling pre vious l y depic ted in F ig ure 5 . T he bott om plot depic ts the horizont al com ponent of the error , b y plott ing the Nort h vs t he East err or. In th is cas e, we do not appr eci ate a d egrad ati on of the err or. T he reason f or s uch as ym m etr y in the ver tica l and hor izo ntal is an exam ple of quest ion pos e d to the s tude nts us ing g LAB i n the l aborat or y sess ions. T he a na lysis of the res u lts ra ises interest in g ques tions and discus sions that l ink the obs erve d results w ith the t he oretica l aspect s seen in t he lec ture s. 5. Conclus ions gLAB is a usef ul tool to lear n about G N SS d ata proces sing or to expa nd a n y prior k no wledge. Using actua l dat a s ets c olle cted b y t he public l y availab le IG S net work , we give a n exam ple of a straight f or ward proc edu re ta ilore d to understa nd an d ques tion th e eff ec ts of dif fer ent error com ponent s in bot h SIS dom ain and the T he gLA B tool su ite can be downloa ded toget her with diff erent B ook s and T utorials on GN SS Dat a P roces sing f rom our w ebsit e gage. upc. edu. Acknowledge ments T he present wor k was suppor ted in par t b y the by proj ect R T I2018 - 094 2 95 -B- I0 0 f rom the Agenc ia Españ ol a de In vesti gaci ón of the Spanish Mi nistr y of Sci enc e, Inn ovati on and Univers ities MCI N/AEI 1 0.1 3039 /50110 001 103, whi ch is co - founded b y th e FEDE R progr am . T he aut hor s ac k nowledge t he us e of data a nd products pro vided b y the Inter natio na l GNS S Servic e. Referen ces [1] Park inson B, S pilk er J, Enge, P. “G loba l Position ing S y s tem , Vols I and II , T heor y and Ap plic ations ” Am er ican Insti tute of Aeronaut ic s: Res ton, V A, U SA, 19 96. [2] Hofm ann - W ellenhof B, Lic htenegg er H , W asle E (2008) G NSS – GlobalNa v igatio n Sate llit e S ystem s . Springer , Vienn a, Austr ia [3] T eunissen PJ, M ont enbru ck O ( 2017) “Spri n ger Ha ndbook of Global Nav igati on Satellite S ystem s ” Spring er Cham , Berlin [4] Sanz J, J u an JM, Hern ánd ez - Paj ares M , (2013) “ GNS S Dat a Proc e ss ing, Vol. I: Fundam entals and Algor it hm s; EST EC TM - 23/1” E urope an Sp ace A ge nc y Comm unications: No ord wijk , T he Nether lands . [5] https:// www .navce n.us cg.g ov/?D o=c onst ellation Stat us [6] https:// www.gsc - europ a.eu/ s ystem - serv ice - status/c o nstel latio n - inf orm ation [7] https:// www.g lonass - iac.ru/ en/s osta vOG/ [8] http:// en.be ido u.gov.c n/ [9] Europ ean Uni on Agenc y for t he Spac e Program m e ( 2022) “EO and GNSS Mark et Repor t Iss ue 1, 20 22” . Publicat ions Of f ice of the Europ ean Unio n 52 DOI: 10.5821/conference-9788419184405.010 4 th Symposium on Space Educational Activ ities Barcelona, April 20 22 Page 6 of 6 [10] Interna tiona l T elecom m unic ation Unio n (2021) “ IT U - R: Ma nagin g th e rad io - fr equenc y spec trum for the world ” [11] Kalm an R E (1960) A New Appr oach to Linear F ilter ing and Pred icti on Prob lem s. T ransac tions of th e A SME – Journ al of Basic Engine erin g 8 2, 35 - 4 5. [12] Ibáñe z - Segura, D. Ro v ira - Garc ia A, Alonso, MT , S anz J, Jua n JM, Gonzá lez - Casado G , Lópe z - Martí nez M. “EG NOS 1046 Maritim e Service As ses sm ent”. Sensors 20. [13] San z J, Ro vir a - Gar cia A, Her nán dez - Pajares M, J u an J M, Ventur a - T raveset J , López - Ech azarr eta C, "T he ESA /UPC GNSS - Lab T ool (gL AB): An adva nce d educat iona l and prof es sio nal pac k age f or GNSS data proc ess ing and anal ysis" , Proceed ings of T oulous e Spac e S ho w 2012 4th Int ernat io nal Conf er ence o n Space Appl ications , Ju l. 2 012 [14] United Sta tes D epartm ent of Def ense (2020). Globa l P osit ioni ng S ystem Standar d Pos iti oning Ser vic e Perf orm ance Sta ndard . [15] Beutler G , Ro thach er M , Schaer S, Springer T , Kouba J , N eilan R. T he Interna tiona l G PS Ser vic e (I GS) : An interdis cip linar y ser vice i n suppor t of Earth sciences. Adv. Sp ace Res. 199 9, 23, 631 – 653 . [16] Montenbr uck O , Stei g enber ger P, Prange L , De ng Z, Zha o Q , Per osan z FJ , Rom ero I , Noll CE, St ür ze A, W eber G, et al (2017) “T he Mult i - GNS S Exp erim ent (MGEX) of the I nter nat ion al GN SS Serv ice ( IG S) – Ach ievem en ts, prospec ts and cha lleng es” . Adv ances i n S pace Resear ch 5 9, 1671 – 16 97 [17] Interna tiona l GN SS Ser vice (20 22) https:// igs.or g/net wor k / [18] Klobuch ar J A ( 1987) . I onos pheric T im e - Dela y Algor ithm f or Sing le - Frequ enc y GPS Us er s. IE EE T ran sac tions o n Aerospac e an d E lectro nic Syst em s 23, 325 – 331 53 DOI: 10.5821/conference-9788419184405.010 4 th Symposium on Spa ce Educat ional Acti viti es Barcelon a, Apr il 2 022 Page 1 of 6 Analysis of planetary sp acecraft images with SPICE Teresa Peña 1 , Manel Soria 2 , Paula Betriu 2 , Enrique Garc ía- Melend o 2 __________________________________________________________________________ Abstract S pacecraft images are an invaluable source of information in Planetary S cience. However, they must be proce ssed and the ini tial stage is to navigate them , i.e., de termine the longitude and lati tu de coordinates of each pixel on the image plane. The mai n goal of the present work is to develop an open - source tool to do so. It will be independent of proprietary software and implement ed in a widely used languag e (Java, Python ). It will be able to analyse planetary images taken by different spacecra ft, such as New Hori zons, Cassini or Voyager , with mini mal user intervention . Here we present the first steps of the process ill ustrating the techniques to navigate an image of an ell ipsoidal body , obtained from mi ssion kernels using NASA Jet Propulsion Laboratory SPICE library , considering that the att itude and position of the spacecraft are available ; correct the camera attitude information; determine the image resolution for each pixel; and combine different images of a body to generate mosaics with high resolution. Keywords Planetary Scienc e, Planetary Image Processing , SPICE , Open Sof t ware __________________________________________________________________________ 1 Universit at Poli tècnica d e Cataluny a , ESEIAAT, teres a.pen a@estud ianta t . upc.edu (Student) 2 Universit at Politècnica de Catalunya, ESEI AAT, Aerospace Engineering / Physics De partment, Spain . 54 DOI: 10.5821/conference-9788419184405.011 4 th Symposium on Spa ce Educat ional Acti viti es Barcelon a, Apr il 2 022 Page 2 of 6 Nomenclature CCD Couple - Charged Device FOV Field of Vi ew SPICE Spacecraft Plane t Instrument C - matrix Event s [4] . 1. Introductio n Spacecraft images are an inval uable source of informat ion in Pla netary Science . To mention just one exa mple, in atmosphe ric science they can be used to measure wind velocities and track the ev olution of storm s [1 ,2 ] . The first step to process the planetary images is usually to navigate them [3] i.e., determine the longit ude and latit ude coordinates of each pixel on t he image plane. In order to do so, accurate informat ion about the position of the spacecraft and the attitude of the optical inst rument are crucial . These data are usually pr esented in t he form of kernel files generated by the mission and processed with the SPICE library [4] . However, attit ude ker nels (C - kernels ) ar e sometimes not available at all (Voyager) or not entirely accurate ( Cassini [5]). Many resear chers have put thei r effort s on finding the way to proces s the images with very precise data sets. In [6] a photogrammetri c control network to generate accurate mosaics of Jupiter’s moon Europa is developed . In [3] , the authors present a software package called PLIA (The Planetary Laboratory for Image Analysis) to navigate and process images from di fferent missio ns . The present work is aimed to eventually develop an open - source tool for planetary i mage analysis that does not rely on proprietary software (such as IDL or MATLAB), minimi zes the need of human inte rventi on in the navigation process , provides an estimation of the navigation error for each image and can be used to process images of different missi ons. Here , as a first step towar ds the af orementioned goals, we present algori thms to (a) Navigat e an image of an elli psoidal body , assuming that the exact attitude and position of the vehi cle are available; (b) Correct the camera attitude informat ion; (c) Obtain th e image resolution for each pixel; and (d) Combine different images of the same body in a mosaic to obtain a fu ll projection, choosing t he best resolution available for each region . 2. Image projection from known spacecraft position and instrumen t attitude As suming that the attit ude of the camera and the position of the spacecraft are perfectly known , the nav igation of the images could be performed with the algo rithm outlined in this section. An exam ple of an i mage where lit tle correction is needed is presente d in Figure 2. 2.1. Project ion of a point i n the i mage plane Consider a poi nt on the body surf ace (Figure 1), expressed in its fixed frame, 𝑃 ( 𝑋 ! , 𝑌 ! , 𝑍 ! ) , T he rotation matrix from the body frame to the instrume nt frame, at the instan t of the image, can be obtained from the kernel data with the SPICE function cspice_pxform . Afterwards, the rotated vector is translated to th e location of the instrume nt by determining the rel ative position of the frame with SPICE function cpsice_spkpos . Once the position of 𝑃 ( 𝑋 ! , 𝑌 ! , 𝑍 ! ) is expressed in the fra me of the instrum ent as 𝑃 ( 𝑋 " , 𝑌 " , 𝑍 " ) , it is projected on the image plane and converted in to pixels, using the intrinsic matrix of the camera [7] : 𝐾 = ⎣ ⎢ ⎢ ⎡ ± # $ 0 c % 0 ± # $ c & 0 0 1 ⎦ ⎥ ⎥ ⎤ (1) where F is the focal length of the camera, ρ the size of the pixels and c % and c & the coord inates of the optical centre of the FOV (point C in Figure 1) . The homogene ous coordinat es of 𝑃 6 ( 𝑢′, 𝑣′, 𝑤′ ) can be expressed as: ; u ' v ' w ' ? = K · ; X ( Y ( Z ( ? (2) and finally converted to Cartesi an with: Figure 1 . Proje ction o f a sur face p oint i n the image p lane 55 DOI: 10.5821/conference-9788419184405.011 4 th Symposium on Spa ce Educat ional Acti viti es Barcelon a, Apr il 2 022 Page 3 of 6 𝑢 = ) ! * ! 𝑣 = + ! * ! (3) i n order to obtain t he coordinat es of 𝑃 6 , the projection of P . 2.2. Image navigation The navigat ion of t he image i s carried out scanning each pi xel of the CDD to determine if there is a surface point of the pl anet projected on it and visible from the spacecraft. To do so, the intersection points between the ellipsoi d and a l ine of si ght , which emanates from the centre of the i nstrument 𝑂 (Figure 1), goes through the pixel 𝑃 6 considered and continues to infinit e, has to be obtained . The equation to determine the inter section between the line of sight and the ell ipsoid can be expressed as: ( 𝑆 + 𝜆 𝐿 − 𝐶 ) , 𝐴 ( 𝑆 + 𝜆 𝐿 − 𝐶 ) = 1 ( 4) where 𝑆 is the position of the spacecraft , the scalar 𝜆 (the unknown) is the distance between the center of the ins trument frame 𝑂 and the body, 𝐶 is the center of the body , 𝐴 is a parametri z ation matrix descri bed below and 𝐿 is a unitary vector defining the line of sight of each pixel . A ll the magnitudes are expressed in the reference frame J2000 (equivalent to the International Celestial Reference Frame [8] ). 𝐿 is the ve ctor of the line of sight expressed in t he frame of the camera. Regarding the matrix A, defined in the pri ncipal axes of the ellipsoid and composed of the equatorial 𝑟 - and pol ar 𝑟 . radii of the body , it is: 𝐴 = ⎣ ⎢ ⎢ ⎢ ⎡ / 0 " # 0 0 0 / 0 " # 0 0 0 / 0 $ # ⎦ ⎥ ⎥ ⎥ ⎤ (5) Eq. 4 is expressed as a second - degree equation , whos e discriminant ∆ is solved . W hen its value is null or positive, the line of sigh t intersects t he ellipsoid in one or two points, respectively . T he smaller value of 𝜆 is the one referring to the point in the near - fac e of the body . Then , the surface points of the ellipsoid are calculated and converted from J2000 to the body - fixed frame by means of a rotation and a tra nsla tion as described in sub - section 2.1. A part from imposing that the intersection point must be on the edge or inside the body, it is also necessary that it is illuminated to be seen fr om the spacecraft and shown in the image. Function cspice_illumin from the SPICE library is used w ith this purpose. Once the previous require ments are verified, the longitud e and latitude associated to the surface poi nt proj ected in each pixel are computed . These values can be obtained with two SPICE function s , cspice_reclat or cspice_recpgr , de pending on the system that wants to be use d to express the lon/la t v al ues, the planetoce ntric or the planeto graphic one. 2.3. Image projection In order to obtain the projected image, the intensity asso ciated with each lon/lat is needed. Figure 2. Theoreti cal limb of Pluto in New Horizon’ s image 2 991474 81 [9] . The diff erence bet ween t he li mbs p osition pr edicted with the missi on k erne ls and t he i mage can be seen more clearly in the z oo med area . Figure 3. I mage p roj ecti on of Plut o fr om New Horizon’ s image 299147481 [9 ] generated from Figure 2. 56 DOI: 10.5821/conference-9788419184405.011 4 th Symposium on Spa ce Educat ional Acti viti es Barcelon a, Apr il 2 022 Page 4 of 6 To com pute i t , we use an interpolation algorithm based on t he triangulation of the intensity data obtained from the or iginal image . In order to consider that the intensity of a pixel obtained from the interpolati on i s val id, the surface point associated to it has t o be (a) inside the FOV of the camera and (b) in the near face of the planet or moon. The first condition is verified by co mputing the location of the pixel in the image plane and, for the second, the angle between the position vector of the surface point and the one that has its origin in this point and its end in the space craft is com puted . If this angle is smaller than 90º, the point is located in the near - side of the body and the int erpolated intensity o f the pixel is main tained. If one of the previous two conditions is not fulfilled, the in terpolat ed intensity is changed into a spe cific value , such as 0 , so in the image the pixel under consideration is displaye d in black . To inc rease t he qu ality of the projection , image processing techniques ar e used and, more specifically, sharpening and contrast adjustment. Th e final result can be seen in Figure 3. 3. Attitude cor rection fr om known planetary l imb position If the attitude of the camera is not perfectly known , the image navigation provide s wrong results that lead to unreal ima ge projecti ons or mosaics . In fact, even the proje ction of Figure 3 , where th e kernel is quite ac curate, does not coincide perfectl y with t hat provided in [ 10 ], since the longitude is s lightly different. The in accuracies in the data are manifested as a displacement of the posit ion of the body wit h respect to the one that can be seen in the image. In o rder to correct this mismatch , th e p rocedure that is proposed here consists of determining the rotation around the axes of the instrume nt ( with the att itude provided by SPICE) necessary to make coin cide the position s of the body. 3.1. Limb points on t he image The ai m of th is work is to provide procedures that can be used with the majority of images in which all or a part of the limb of the body is displayed. However, when t rying to generate the limb of the planet or moon directly from the original image, there are f actors that make it very complicated to do it with completely automatic methods that do not require the intervent ion of the user , such as t he presence of rings in the images of Saturn or the dark zones of Pluto in the images taken by New Horizons . Because of th is, here we propose a method characteri z ed by the generation of a limb defined by as many points as desired, whi ch follow t he limb that can be seen in the image and are computed in the same way . Thus, is the user who chooses the zones in which the limb points should be located and the algorithm computes the exact pixel . To do so, it first determines the averag e intensity of th e pixels of the ba ckground and those of the planet. Then, the mean of these two values is calcu lated to know the intensity that the pixel where the limb point will be located should have . 3.2. Theoretic al limb po sition As t he points of t he l imb from the i mage a re expressed in pixels, the limb generated with the SPICE data (i.e., the theoretical limb) also has to be exp ressed in th is units in ord er to be compared. The theoret ical li mb is defined i n the body - fixed frame by the main parameters of a conic (i.e., center and major and minor semi - axes) , obtained from SPICE function cspice_edlimb. F rom them and the para metric expression of a n ellipse in 3 - D, an arbitrar y number of points that are part of the conic can be generated and afterwards converted into pi xels to be shown in the i mage. To do so, a rotation and t ranslation of their position vector from the body - fixed frame to that of the instrument is performed as described in previous s ections. 3.3. Correct ion proce dure To co rrect the mismatch between the limbs of the body, the frame of the instrument is rotated causing a variation in t he position of the theoretical limb. To do this, the rotation mat rix that ma kes co incide almost perfectly both limbs ha s to be foun d. This matri x is de fined by the angles of Euler ( α, β, γ ) and i s applied to the coordi nates of each poi nt of the conic expressed in t he f rame of the instrument: ; X " ! Y ( ! Z ( ! ? = 𝑅 1 ( γ ) 𝑅 2 ( β ) 𝑅 3 ( α ) ; X ( Y ( Z ( ? (6) To find the combination of angles t hat generates the best fi tting, an iterative minimi zation proc edure is used . The parameter 57 DOI: 10.5821/conference-9788419184405.011 4 th Symposium on Spa ce Educat ional Acti viti es Barcelon a, Apr il 2 022 Page 5 of 6 to minimize is 𝐷 , the sum of the di stance s 𝑑 4 between each limb point 𝑝 4 and its projec tion on the theoretical limb conic 𝑡 4 . 𝐷 = 𝑚𝑖𝑛 [ ∑ ] ^ | 𝑝 4 − 𝑡 4 | ^`a (7) The minimiz ation starts with arbitrary angles, such as a tenth of the angular field of view of the camera, and after a few iterat ions t he error is notably reduced, provided that the number of limb points is sufficient. Once the right E uler angles have been obtained, they are used to generate the correspondi ng rotation matri x. 3.4. Applicat ion of the correcti on to the image navigation When the ro tati on matr ix that corre cts th e attitude of the spacecraft has been computed, i t has to be applied to the image navigation procedure and, more specifically, to the pointing vector ( 𝐿 in Eq. 4) used to defined the position of each pixel of the CCD. In the cas e presented in Fi gure 5, the Euler angles are (0.0024 ° , - 0.0032 ° , 0.03 52 ° ) and the total distance or error between limbs is 0.814 pixels. 4. Generati on of i mage mosai cs An i mage mosaic can be def ined as the union of multiple image projections, in such a way that the range of longitude and latitude displayed is wider th an the on e t hat coul d be shown in each individua l image projection. For ea ch pixel, t he image w ith best resolution is selecte d. The resolution in pixels/meter is com puted as the square root of the surface that covers each pixel , which is define d by the m ean verti cal and horizontal distances between t he pixel whose resolution wants to be determined and the adjacent pixels i n each direction. As the pixels are associated to a longit ude and latitude , Vincenty’s formula [11] is used t o compute t he geodesic distance between t wo pixels on the surface of an elli psoidal body. As wit h t he i ntensity of the pixels in the image projection , the resolution is also interpolate d to obtain the correct value associated to the lon/ lat of the pixels. The inter polation algorit hm is based , as well, on the triangulation of the resolution data obtained from the or iginal imag e. Once the inten sity o f the pixels and its resolu tion for each image have been filtered, the data of the image mosaic can be generated by selecting, f rom the multiple images, the pixels with a hi gher resolution. 5. Results & Discussion To ill ustrate the procedure described in this article, the image mosa ic of Figure 6 is presented . Here each image has been represented w ith a different color for clarity. 6. Conclusions The results provided c onfirm that the fi rst steps of the work that will end i n the development of an open - source tool for planetary i mage analysis have been completed. Figure 5 . Co mparison of the theoretical and corrected limbs and terminators of Saturn in Cassini ’s i mage 14614 06214 [9]. Figure 4 . Iteration of the minim i z ation in Cassini ’s i mage N151616 9656 of Encel adus [ 9]. 58 DOI: 10.5821/conference-9788419184405.011 4 th Symposium on Spa ce Educat ional Acti viti es Barcelon a, Apr il 2 022 Page 6 of 6 We are now able to navigat e images obta inin g accurate longit udes and lat itudes, by means of a correction procedure based on an estimation of the camera kernel er ror. However, there are still a few aspe cts that should be addressed in the near fut ure : (a) the Newtoni an light time correction and stellar aberration correct ion; (b) the analysis of images in which the kernel files are not available, such as t hose of Voyager 1 and 2; ( c ) the treatment of images without limb; ( d ) the esti mation of the error in the image projecti on due t o inaccuracies in the attitude of the instrume nt or the selection of limb points ; and ( e ) the estimation and correction of the spacecraft position when multip le star s and a body are visible in the image. The final algorithm will be implemented in a widely avail able and portable language such as Java or Python. References [1] A. Sánchez, E. Garc ia - Melendo et al, A complex storm system i n Saturn's north polar atmosphere in 2018 , Natur e Astronomy , 1 - 17, 2019. [2] E. García - Mel endo, S. Pérez - Hoyos et al, Saturn's zonal wind p rofile in 2004 – 2009 from Cassini ISS images and its long - term v ariability, Ica rus , 215 , 62 - 74, 2011. [3] R. Hueso, J. Legarre ta et al, The Planetary L aboratory f or Image Anal ysis (PLIA), Advances in Space Research , 46, 1120 - 1138, 2010. [4] The SPICE Conce pt. NAIF Website: https://naif. jpl.nasa.gov/naif /spiceconcep t.html , last visited: 1 8 th March 20 22. [5 ] Th. Roatsch, M. Wählsich et al, Mapping of the icy Saturni an satell ites: Fir st results from Cas sini - ISS, Planetary and Space Science , 54, 1137 - 1145, 2007. [6 ] M. T. Bla nd, L. A. Well er et al, Improvin g the usability of Galileo and Voyager images of Jupiter's moon Europa , Earth and Space Science , 12, e2021EA001935 , 2021. [7] Geomet ry of Imag e For mati on. LearnOpenCV Website: https://learnopencv. com/geometry - of - image - fo rmation/ , last visited: 10 th March 2022. [8] Reference Fr ames. NAIF Website: https://naif. jpl.nasa.gov/pub/nai f/toolkit_d ocs/C/req/frames.html , last visited: 19 th March 2 022. [9] OPUS3 Websi te: https://opus.pds - rings.seti.org/#/cols= opusid,instrume nt,p lanet,targ et,time1,observa tiondura tion& widgets=i nstrument, observati ontype,tar g et&order=time1,opusid&view=search&br owse=gallery&cart_browse=gall ery&star tobs=1&ca rt_startobs=1& detail= , last visited: 18 th March 2022. [ 10 ] S. A. Stern, F. Bag enal et al, The Plu to system: I nitial results from its exploration by New Horizons , Science , 6258, aad1815 - 2, 2015. [1 1] C. Thomas an d W. Featherstone , Validati on of Vincenty’s Formula s for the Geodesic Usi ng a New Fourth - Order Extension of Kivioja’s Formula , Jour nal of Surveying Engineeri ng - asce - J SURV ENG - ASCE , 131 , 2005. Figure 6 . Color ed i mage mosai c o f Rhe a from Cassini ’s i mages N15117 00504 , N1511 717371 and N149999716 9 [9 ]. 59 DOI: 10.5821/conference-9788419184405.011 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 1 of 6 S D R H e l i x A n t e n n a D e p l o y m e n t E x p e r i m e n t ( S H A D E ) o n b o a r d B E X U S Meli na Koukou 1 , Vasi lis Vel liki s 1 , Ioannis Va rvaringos 1 , Konstantino s Koutro poulos 1 , I oannis Myrsinias 1 , Despina Ekat erini Argiropoulos 1 , Andr onikos Dourmisis 1 , Ores tis Rafail Nerantzis 2 , Ioannis Ioann ou 1 , Elli Loukaridou Kizi li 1 , Spyros Megal ou 1 __________________________________________________________________________ Abstract In t he field of space travel, space communica t ions has always presented a slew o f obstacl es and hurdles that must be overcome in order to complete a success ful missi on. Space limits inside a satellite or spaceship, vast dista nces betw een satelli tes and ground stations , and a phenomenon known as "Faraday R otat ion " in the ionosphere are only a few of the most typical issues. Sa tellite an tennas must b e s mall, compac t, efficien t, and circularly p olarized as a result of the aforementioned issues. The heli x an tenna is an excell ent ans wer for all of the requirements . In this work we de velop a deplo yment and poi nting mecha nism of a helix antenna opera ted wi t h software defined radio algorithms. The f eatur es of hel ix antennas a re exceptional, and they are especial ly suitable for sa tellite communicati on. Three coaxial cylinders, two stepper motors, one pulley, and o ne thread make up a deployment-pointing mechanism. The mecha nism deploys the antenna along its longi t udinal axis and turns it horizontally toward s the ground station. During the flight, the antenna is deployed and retracted. Unde r differe nt position ing situations, the GPS, an altimete r, and a compass calculate the gon dola's position in order to ro tate the anten na towards the Ground S t ation and close the com m unication link. The antenna's ro t ation mechanism is tr iggere d by the integra t ed attitude determination and control sys tem algo rithms in order to correct the pointing and orientation towards the Ground Station. The antenna uses software defined radio algorithms to achieve weigh t an d volume reductions while maintaining high efficiency and reconfigurabili t y. The ex periment includes a high-definition camera that provides real- time information on the anten na's orienta tion and condition. SHADE 's flight on the BEXUS 28/29 balloo n resulted in ef f ective deployment and tran smission, a s well as t he abili ty to r eceive and decode trans mitt ed pack ets. The rotati ng mecha nism met the pointing requirements, and all of the sensor's data was correctly saved to our syste m. Throughou t the trip, there were no signs of the r mal risk. Keywords Antenna D eployment, Helix A ntenna, REXU S/BEXUS , Sof tware Defined Rad io, Stratosp heric Balloo n __________________________________________________________________________ 1 Corresponding a uthor: Aris totle univers ity of Thessal oniki, Gre ece, mkoukou8 @gmail.com 2 University of M acedoni a, Greece 60 DOI: 10.5821/conference-9788419184405.012 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 2 of 6 Acronyms/Abbr eviations: ADCS Attitude Deter mination & Control System AUTH Aristot le Univers ity of T hess aloniki BER Bit Error Rate DMCS Deployment Mechanism Control System FEM Finite Element M ethod GH z Giga-Hertz GMSK Gaussian Minimum Shift K eying GNSS Global Navigatio n Satellite System GS Ground Station HCS Heating Control System HPBW Half Power B eam Width LNA Low Noise Ampl ifier OBCS Observation Con trol Syste m PA Power Ampl ifier RX Receiver SDR Software Defi ned Radio SHADE SDR Helix Ante nna De ployment Experiment SSC Swedish Space Corp oratio n TT&C Tele metry Track ing and Comma nd TX Transmitter TX CS Transmission Control System 1. Introduction In space te lecommu nication s ystems, closing long distance links and F araday rot ation are major c hallenges face d by engineers. Stratospheric balloons an d oth er high-altitu de platforms r egularly us e monop oles to communicate with the gro und s tation, as t heir omnidirectiona l pro perties nullify any need for beam steering. Neverthele ss, monopoles have low gain a nd linear polariz ation that c ould be easily affected by Faraday rotation; th erefore, they require high powe r consumption to establish a link. Helix ant ennas could offer a solution to t hese issues, wit h their g ood gain/cost trad e-off and c irc ular polarizat ion tha t they provide. Even though they are wi dely used in aerospace communica tion systems , the geometry of this anten na type, resembling a relatively long and w ide spring, often v iolates the volu me restrict ions set i n spac e applications. In ad dition, following a present tende ncy in research and ind ustry to r eplace conve ntional communication circuits w ith softw a re cores , Software Def ined Ra dio (S DR) techn ologies are gradually es tablished in the s pace s ector. SDR offers accurate signa l pr ocess ing applications without unneces sary phys ical c omponents in small sized mod ules. SDR H elix Antenna Dep loyment Exper iment (SHADE) is an SDR operated helix an t enna with a s pring-b ased deployment mechan ism and a Ground- Stat ion-Trac king automation system. A hel ix anten na, pr otected by a t eflon cover, is opera ted by an SDR module that transmits d ata to the g round s tation. To compensate for t he narrow beam width, an automation sys tem h as been develo ped in order t o ens ure t hat th e antenna will always point at the ground station a nd maintain Telemetry Tracking and Command (TT &C) applications. Moreover, a deployme nt mechanism has been i mplemente d whic h exploits t he antenna's s pring c harac teristics ensuring a reduce d size for the s ystem. The exper iment's potentia l was recogn ized by REXUS/BEXU S progr amme [1] , [2] and SHAD E was desi gned, imple mented and had a success ful flight on bo ard a s tratospheric balloon. The s tructure of the pr esen t paper is firstly the Introduction, s econdly the Mechanical D esign followed by the Ther mal Des ign; after that is the section of the Electronics and Softw are and the n th e last technical secti on, the Telecommunicat ions section. The final s ections include the Testing an d Verification an d Conclusion, on which the les sons lea rned are described, acknowledg me nts and refere nces are also cited. 2. Mechanical Design The Mech anical Design aimed to satisfy the following r equirements. 1) The antenn a’s deployment 2) the antenn a’s controlled r otation 3) the overall fixat ion of t he experim ent o n the gondola 4) BEXUS space a nd w eight limitat ions 5) the safety of the experiment’s assembly during the “cut- the -r ope” phase. T o ac complish these r equ irements, the mechan ical des ign consisted of 1) the Anten na’s C asing, wh ich contained the helix antenna, 2) the External Box, which co ntain ed the rotat ional mech anism and t he m otors for de plo yment and r otation respectively 3) the Electro nics Box and 4) th e 61 DOI: 10.5821/conference-9788419184405.012 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 3 of 6 hum anities and social sciences, exact sciences and t echno lo gy, or biom e dical scie nces. Th e initial trainings of t he influx s tud e nts are very diver se but s ha re a common thread: that the stude nts demonstrate a str ong interest in the space s ector an d t hat the y are a ble t o pro ject their fut ure self in a topic re l evan t t o space. In some m ore detail, t he MSS is a 6 0 E CTS pro gr am, ta ke n up as a 1-yea r full -time o r a 2- year pa rt-time program (Fig u re 1) . Th e man dat ory c ommon core of 29 ECTS acquaint the students with the diff erent aspe cts that toge the r fo rm t he f oundation of sp ace -related activities. Mandatory c ourses cover l aw & policy, spa ce missions and sate ll ite technolog y, sciences aspec ts and earth observations Depen ding on th eir backg r ound a n d int ere sts, the students the n deepen their existing knowled ge th rough more domain -specific optio nal cou rses, for a total of 16 ECTS. The se cour ses cover the d oma ins of (i) Space Law, Policy, Business and M ana g eme n t, (ii ) Space Sciences – which is very bro a d and covers topics ranging from sp ace wea th er to r adiation physics , to life s ci ence – (iii) Spac e Te c hno logy and Applicati ons . Stu dents can furt hermor e choo se cou rses fr om other master p rog ram s at KU Le uven a nd Gh ent Unive rsity, as l ong as they ar e appropriate for th eir mast er thesis or their fut ure profe ssi ona l p roject. Th e master thesis is the final part of the inter disciplina ry program, in which the acq uired knowled ge an d int erdisciplinary skill s are app lied t o a compl ex and concrete p roj ect. T he mast er thesis is a fo ur mon t hs p r oject mostly per for med i n t he s econ d s em ester du ring which the st udent is embedded in a research team at KU Leuven or G hent U niver si ty, or at an exter nal institute, o rganisation or private par tne r, under th e supervision of an ac ademic pro mot or. Th anks to the interuniversity e ffor t of the pro gr am, stud ents get e mbedded in the acad emic r esea rch expertise of two inter nati onally-ranked Belgia n universities. Fu rthermore, the pro g r am benefits f rom high- pro fil e lect ure rs, in cluding F r ank De W inne, one of two Belgian astronauts, or Prof. Sarah Baatou t, he ad of th e Radiobiolo gy Unit of the Belgian N uclear Research Ce ntre; as w ell as sever al int ernational experts speaking in the year ly lecture s eries of th e KU Leuven Ce ntre for Global Governance Studies. Fina ll y, ex tracurricular initia tives ar e ta ken to brin g the stu den ts i n contact with actors in the differ en t fields of sp ace stu dies. Each year stude nt exc ursions are organised, including visits to the E uropean A stronaut Center in Cologn e, Ger many and the E uropean Space Resear ch and Researc h and Tec hno logy Centr e (ES TEC) of E SA in Noordwijk (NL) and the Belgian Nucle a r Re sear c h Cente r ( S CK - Cen) . Whene ve r re leva nt, students are given the opportunity to tak e pa rt in a va riety of natio nal a nd inte rna tio nal events. R ecen t Figure 1 . MSS program structure. (*) Students can also include courses fr om other master programs at KU Leuven or Ghent University. (* *) Depending of the profile of the student: students with an initial master in Science or Technology have to follow (a) while students with a Humanities background will foll ow (b). 68 DOI: 10.5821/conference-9788419184405.013 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 4 of 6 exam ples encompass t he ES A Y oung Laywe rs’ Symposiu m, t he Luxembourg NewSpace Europ e Conf ere nc e or th e Belgia n Switch to Space event, allowin g students to e x pand the local expertise , int eract wit h indus try lea der s, policyma kers a nd rese arch experts, g row their netwo rk and explore new career opportun ities. 3. Pr og r amm atic analysis T he MSS program is nearing the e nd of its 1 3 th acad emic ye ar and has gr aduated o ve r 100 stude nts si nce it was first offered in 2009- 2010. Th is pr ovides us a n inte resting sam ple of alum ni sp ecifically tr ained to e nter th e spa ce sector . In this secti on, we investig ate the dem og raphics of the progr am, including atte ndance, gen d er balance a n d th e dist ribution of stu dents among the main study profiles. In a secon d step, we use s ocial me dia a nd p e rsonal conta cts to t race th e c urr e nt pr ofessio n al occup ation s of the pr o gram’s a lumn i t o identify the secto r (spa c e- vs. non-spa c e-relate d ) an d subse ctor s (academ ia, (inte r)governmen t al age ncies, in du stry ) in which th ey are w or ki ng. Fina ll y, we use the results o f interviews from alum ni to sh ed some additional perspective s offe red by young professional on the space edu cation. 3.1. MSS demog r aphics Stud e nts’ influ x : Figure 2 displays the nu mber of stud ents that h ave ent er ed t he program for each ac adem ic year. W ith an influ x rate of less than 10 stud ents per yea r in the first few years, the influx rate h as m ore than d o ubled in t he last coup le of y ear s with cur rently no less than 29 stude nts registered fo r the a c ad emic y ear 2 021- 2022 (22 new stud e nts and 7 st udents spre adin g th e 60 -ECTS program ov er two year s) . A s the re ader wil l notice, Poisson e rror bar s t hat ar e app ropr i ate for c ounting statistics have been overla id in Figu re 2. Of course, one exactly knows t he n umber of registered stude nts each year , so one may wond e r “ Why err or bar s ? ”. A s data scientists woul d explain, conside rin g th e num b er ( N i) of regist ere d stude nts eac h year ( i) as the r ealization of a ran do m va riable ( X N ) allows us t o inv estigate wheth er the observed ye a r- to -ye ar variations can be explai ned b y sta tistical fluctuations du e to random s am pling of a consta nt pa rent pop ulation or w hether sig nificant time - dep end i ng trends can be identified. Fo r ex am ple, the 2012 and 2018 pea ks in Figu re 2 ar e by n o mean significan t, nor is th e 201 0 valley. Yet, the incre ase obse rved of the last cou ple of y ear s c anno t b e exp l ained by statistical fluctua tio ns around a co nstant aver ag e ( null hy pothesis r ejected at 99. 9%- confid ence) . This su ggests t ha t an ext ern al facto r came int o play ed to modify the la n dscap e in which st udents cho ose t heir orientation. While the nu mber of students i n t ertiar y edu cation in Belgium grows over th e year s, this cann ot be invo k ed to explain a short- term incre ase by a f act or of more t han 2.5. As an alter nativ e ex planation, one may n ote tha t the incre ase coincides with t he first aca de mic year afte r t he sta rt of th e COVID crisis. On e may ther ef ore w ond e r whether (some) graduating stude nts felt tha t the jo b-market w ould be difficult and have t here f or e chosen to pu rsue a comp lem entar y (post-m aster) e ducation to incre ase thei r attra ctivity on the markets while weath erin g the crisis. Interac tions with the stude nts r eve aled h owever a diffe rent m essage in which they put forward th eir long -lasting inter est fo r spa ce, the pe rceived attr activity of the sector an d the larger me dia att ention to space- r elated news. Ti me will c erta inly he l p to differ en tiate between the la t ter t w o hypo t he sis. Figure 2. Number of students registered in the program per academic year. Poisson errorbars have been included. Figure 3. Distribution of students among the three specialization profiles of the MSS. 69 DOI: 10.5821/conference-9788419184405.013 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 5 of 6 Gen der balance : A si milar an alysis can be don e with res pect t o the gender of t he st udents’ pop ulation . Fr om 20 09 to 2017, t he fraction of fem ale students w as on average o f 14% while , since 2018, it s average n ow r eaches 32%. The post- 20 17 fraction of female stude nts ca nnot be explain ed b y statistical fluctuation a round the pre -2 017 rat e and should there f ore be conside re d as si gnificant ( null hy pothesis reje cted a t t he 95% -confidence) . Th e beginning of the tre nd prec ede s th e star t of t he COVID crisis, and we m ig ht hop e that t his will be a long- lasting tre n d to imp rove the influx of wo men in a sector that h as l ong s tanding g ender im ba lance (as other STEM-related sectors do) . Specia liza tion profiles: Fi gure 3 displ ays the distrib ution s of students across the th ree MSS specializa tion pr ofiles. A vera ges a re 28 %, 25% and 4 7% for the Law & H umanities, S cience and Te chno l ogy profiles, respectively. Our analysis reve als no s tatistically significa nt trends alb eit smaller sa mple sizes may limit our sensitivity. Int er nationalization: A last tr end of inte r est is the larger intern ationa li zati on of th e pr og ram, with an influ x from abroad that h as do ubled, fro m an av erage of 11% f rom 2009 to 2017 to an average of 2 2% in the last 5 ye a rs, des pite a dro p t o pre-pandemic level in 2020. 3.2. P rofe ssional occupation One of th e aims of th e M S S is to h elp pre p aring the students t o star t a career in th e spa ce sector . A possible me tric of success is thus to investiga te th e first professio n al occ upation of the MSS alumn i imm ediately afte r g raduating . Figu re 4 reveals th at a c onsist ent fracti on of f abo ut 70% to 75% of the MSS stud ents find a job in th e spac e sector af ter graduation , but for 202 0 (po ssible impact of t he p andemic?). The rete ntio n rate howe v er decr e ases over the year s and d rops be low 5 0% at th e 10 -year hor iz on. Discussio n with a subset of t he alum ni that have le ft th e sp ace secto r indicate s th at this is rath er the r esult of n ew opp ortunities an d pro fessio nal dev elopments, o r pe rsonal circum sanc es, rather than a lack of option s within th e sp ace sector itself. Among alumni working in the spac e sect or, one may won der which s ub-sec tors the y are working in. Figure 5 re veals a goo d mix of alum ni working in ac ademi a (e.g., researchers and PhD students at universities and research cente rs) , governmental agencies ( e.g., ES A, natio nal a g encies) o r the ind ustry. While the err or bar s ar e large given the limite d sample size, the cle ar ris e of t he p rivate sec tor s ha re (mo stly f ro m wit hin Belgium ) in t he last fou r or five year s seem to sug gest a m o re dynamic Belgian job market and a growin g nu mber of priva te opportunities in the space se c tor. 3.3. Testimo ni als Th e qu ality of th e MSS prog ra m is r egu la rly mon itor ed through s urveys and interviews of our al umni and of representative of the workfo rce. Below, we report on a sm all subset of quotes t hat illustrate th e perception of stude nts and workforce alike. (Alu m ni) “ W hen I fo un d o ut t his Advance d Master existed , I im media t ely app lied. We had all sorts of su bjects. Ca n you imag ine what it must have been like for an eng ineer to h ave Space La w or Life Science s in Space? The diver sity w as exactly what I loved abo ut the Ma s ter .” (Alumn i) “ Anot her aspect of the 1 -yea r expe rien c e t hat changed my li f e was the netwo rking. Because we w ere so f ew in the class, w e became a tig ht g roup . To gether , we Figure 4: Fraction of MSS students with a space- related professional occupation immediately after graduating from the MSS Figure 5 : Distribution, as a function of their graduation year, of the professional sub -sectors (see legend) in w hich MSS alumni w orking in the space sector are w orking. Errorbars have been neglected for clarity but are of 15 to 20% . 70 DOI: 10.5821/conference-9788419184405.013 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 6 of 6 org anise d m any trips to dif ferent kin ds of even ts. ” (Alu m ni) “ T h e dive rse co mpany vi sits allowed me t o really get to k n ow the indus try. Than ks to this m aster, I fo und out what I wanted t o do in life. I b ecame […] . As you can probably im agine , I would never have known this job even existed without this aw esome program .” (Workf orce) “ The re are o nly limited real multid isciplinar y sp aces studi es pr o gra m s availab le, gl obally, a nd th e qu ality of t his pro gr am is, ar guab ly , a mong s t the highest if not the h igh est in academ ic quality pur sang .” (Workf orce) “ T he program is r eally tailored to wher e your interests lie w hile at t he same time giving a ll students the same basis t o bu ild on. ” 4. Oth er space- education activities at KU Le uven KU Leuven hosts ES ERO Belgium [5] , the Belgian antenna of th e E uropean S pace Educatio n Res ource s Office whic h we d o no t deve lop her further for the sake of place. W e rath er focus on a less kn own Cube S pec project [6 - 8] . CubeSpec is a K U Leu ve n-led in -orb it dem onst ration mission that have been selected by the E SA GSTP technology pro gram with a pre li minary launc h date i n 2023. The goal of th e mission is to en able low-c ost astronomical spectr osco py from a 6 -unit CubeSat usi ng an innova tive o ptical desig n and pointing mech anis m. W hile the mission aims ar e scientific and tech nolog ical in nature, CubeSpe c offers si gnificant ed ucational opp ortunities with s everal master th esis pro jects or ganized so fa r around var ious aspe cts of the m is sio n de v elop ment. 5. Con cl usions In this paper, we have reported o n th e adv anced Mast er o f Space S tudies (MSS), an inter disciplina ry post -master tertiary education pro gr am or gan ize d jointly by K U Leuven a nd Ghen t Univer sity. T he ins pection of th e st uden ts dem og raphics and the pr ofessional occu pation of the MSS’ alumni since its cre ation has allowed us to identify a nu mber of inte resting tre nd that we summ a rize below: Studen t de mograph ics • Incr ease in regist ere d students in the last 2 year s • Incr ease in ge nder diversity an d fra ctio n inter nati onal students since 2018 Professio nal marke ts • About 75% of MSS alumn i start a pro fessio nal ca reer in th e space secto r , abo ut 2/3 of which rema i n in the sector 10 year s aft er graduation • Th e pr iv ate sector se ems to be hirin g a larg er fr action of o ur alumni in the last 4 year s, c or rel ating well with its i ncrease role in the spac e sector. Th ese trends ne ed to be consolidated ov er the next few years by further mo nitoring of the stude nts’ po pulation and th eir pr ofessional tra cks, but also by a comp a ris on with similar statistics fr om oth e r b ranches of S TEM edu cation. App en dix: Admission requirements [3,4] As an advan c ed master’s p rogram, app li cants are r equired to have successfully completed an initial maste r’s program before star ti ng the MSS. T he initial t raining can be very diver se (e.g ., L aw, Business, E conomics, Physics, Astrono my, M anagement, E ngine e ring, Design, Psychology, Biochemistry , Medicine, …). A ll app licants mu s t fur ther pr esent a CV and a two- pag e motiva ti on l etter desc ribing the impo rtance of t he p rogram for thei r pr ofessio n al expe ctations, especially in view of their p revious mast er edu c ation . A TOEFL E nglish p roficie ncy test is a lso r equired. Refe rences [1] KNA L website : http s://www.kna lf estival.be [2] J. Borr ell, High Representative and Vice - Preside nt, European Commission , “Op ening address o f the 2020 Eu ropean Space Co nference” [3 ] MSS Website : http s://fys.kuleuven.be/ster/education/m aster -sp ace-studies/master- of -s pace- studie s [4] MSS program and sch edu le: http s://onder wijsa anbod.kuleu ve n.be / op l eiding en/e/SC_51016979.htm#bl=a ll [5] ES ERO Belgium: htt ps://e se robelgium.be [6] Gert et al., Proceedings of th e SP IE , Volume 1 06 98, id. 106985R. (2018). [7] Vanden bussc he et al., 43 rd COSP AR Scientific Assembly. Abstract E1.20- 0015 - 21, id. 150 9. (20 21) [8] Bowman et al., Astro no my & Astroph ysics, Vol. 65 8, A96 (2022) 71 DOI: 10.5821/conference-9788419184405.013 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 1 of 6 D e s i g n a n d o p t i m i z a t i o n o f a r o c k e t s t r u c t u r e f o l l o w i n g t h e r e q u i r e m e n t s f o r t h e E u r o p e a n R o c k e t r y C h a l l e n g e ( E U R O C ) t o b e f a b r i c a t e d u s i n g a d d i t i v e m a n u f a c t u r i n g Jordi Grau Rifà , ESEIA AT UPC SP Spain ____________ _________ ________ ___________ ____ ____________ _________ ________ _ Abstract Amateur rocket str uctures are usua lly ma de of compos ite materia ls , wood or aluminium , the ir in ternal geometries and interf aces are usual ly r estricted by th e available manu facturing t echniques. However, with the app earance of the ad ditive ma nufacturing se ctor new possib ilities arise for the des ign of the structures and its complex ity. In this paper a PA-12 and glass fibr e composite s truct ure for the Phobos rocket is designed wh ich the UPC Space Program a ims t o use to participate in the Europe an Roc ketry chal leng e . The Phobos roc ket structure i s designed and optimized t o be fabricate d u sing additive ma nufacturin g by Hewlett- Packard . The s tructure is desi gned using a lattice appro ach to obtai n a PA - 12 skeleton whic h is then reinforced with a skin of g lass fibre composit e. Moreover, to ob tain the desired structure an optimization methodology is s et usi ng a desig n loop in which the critical sec tion o f the rocket is p arametrical ly optimized to reach the equivalent traditional structure pe r formance. The structure is optimized in the s ize of the lattice ge ometry and in the t hickness of the sk in as parameters. To d o so, the c ritical lo ad duri ng the flight of t he ro cket is i dentified a nd translated to the Nas tran environment to run a parametric optimization of the structural model. The optimized geometry is the n extended to th e r est of the rocket to obtain the overall optimized structure . In addition, severa l analyses are c onducted to valida te the structure be havi our for the di fferent load cases. Finally, both the optim ized critical case and the overall optimized struct ure are compared to traditional design s tructures to obtain conclusive results abou t the us e a nd limitations of the available additive technolo gy an d its mater ials. Keywords Rocketry, Stu dents, Design , Optimizat ion , Structure ____________ _________ ________ ___________ ____ ____________ _________ ________ _ 72 DOI: 10.5821/conference-9788419184405.014 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 2 of 6 Nomenclature T Glass fiber thickness N Number of tr iangles per perimeter BF Buck ling factor ( number of tim es over the critical buc kling load) Acronyms/Abbr eviations EuRoC European Roc ketry Cha llenge ESEIAAT UPC Esc o la Superi or d’Enginyer ies Industrial, Aeroespaci al i Audiovisual de Terras sa UPCSP UPC Space Program HP Hewlett-Pac kard 1. Introduction This paper is based on th e final m aster’s thesis which has the objective to desig n a n optim ized rocket struc ture which aligns with the requirements of the Ares mission insid e th e UPCSP [1] (U PC Space Pr ogram) frame. Th e Ares missio n a ims to partic ipate i n the EuRoC [ 2] (European Rock etry Cha llenge) competit ion, which t akes place in Portuga l using a new rocket called Ph obos. T he Ph obos rock et design mi ght us e addit ive ma nufacturing technologies to im prove several aspects of the rocket str ucture. The final master’s t hesis a ims to optimize the r ocket s tructure minim izing weight and comp aring it to a traditional des ign giving jus tification f or the use of additive manufacture tec hniques i n the final rock et. 2. State- of - the -art ESEIAAT [ 3] (U PC Escola S uperior d’Enginyeries Industrial, Aeroesp acial i Audiovisual de Terr assa) has alway s been involved i n amateur roc ketry with d ifferent student associations. UPCS P has been developing several amateur rockets since 2016. Traditionally, these rockets are made of glass fibre , aluminium, carb on fibre and wood, with either self-made engines o r commercial ones. However, with new tec hno logies such as additive ma nufacturin g tho se designs may be able to be improv ed. M oreover, a lattice structure is sought to be used in the soluti on explaine d in this paper, several solutions can be f ound in the industry such as the A TG Europe [4], wh ich provides composite str ucture sol utions for r ockets or satellites or the United L aunch Alliance [5] which uses a latt ice str ucture milled from aluminium she ets for its fa irings. 3. Methodolog y 3.1. Work s tructure The workflow f or the thesis is the fol lowing: - First a c ritical cas e w ith a c ritical sec tion of the rocket wi ll be set. - A traditional critical sect ion w ill be analysed and used as target for the optimized critical sec tion. - The o ptimiza tion process will be conducted to reach the performance of the traditional design critica l section. - Both designs will be exte nded to the whole rocket. - Several analys es will be conducte d and both rocket desi gns will be compare d. 3.2. Critica l load cas e The critical load cas e use d for the dimensi oning of the desig n is th e buckling failure m echanism . A thin-w alled elongat ed c ylindrical rocket structure could col lapse under t he loads provided by the simu lation de partment of the Ares miss ion inside t he UPCSP. Acc ording to th eir simu lations, t he maximum loads occur during the i g nition stage of th e launch which correspond t o an axial load of 3000 N. T his value w ill be the d imensioni ng l oads of th e design. It is worth to mention tha t due to the small engine and s hort burn time of the r ock et (aroun d two seconds) no th ermal lo ads are consi dered in this study. Th e therma l isolation of the eng ine paired wit h th e thick al u minium wall of its m ount are e nough to not let heat reach the struct ure considering the sh ort burni ng time. 3.3. Critica l section of th e rocket To size t he structure an d optimize correctly the most c ritical section of th e rocket structure is selected to be the pay load bay, wh ich corresponds to a cylinder o f 14 c m in d iameter and 90 cm o f longitude . Is the most critical section due to: - Being the longest empty s ection of t he rocket. - Being the s ectio n need ing more empty space inside for th e payloa d. 73 DOI: 10.5821/conference-9788419184405.014 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 3 of 6 3.4. Design an d Ana lysis metho dology Two design methodologies will be followed. The traditional design w ith ty pical materials alrea dy used by th e U PCSP and t he opt imized design which incorporates additive manufacturing and its correspondin g materials. 3.4.1. Tr aditional design The tradit ional design has the char acteristic of having a thick skin on th e wal ls of th e rock et. This sk in ty pically withstan ds all loads on t he rocket structure, and it is often overs ized for manufacturing purposes. T he typi cal v alues from past UPC SP rockets a re: - Three layers or tw o of glass fibre with a 1:1 ratio in mass to e poxy re sin. A pplied by hand lay -u p. - Interior parts made of w ood or 3D printed PLA po lymer. - Interfaces b etween skin and inter ior geometries gl ued or joined by bolts. 3.4.2. Optim ized design The optimized des ign wi ll be built of one skin of glass fibre and an i nternal s truc ture based on a lattice distribution made of triangles . The internal structure w ill be ad ditive manufac tured. The optim ization procedure for the structure will be the following: - Model w ith N triang les. - Parametric optimization of the thickness of the glass fibre skin, the width, and the height of th e beams of the triangles. - Linear buck ling analys is on the optimized structure. - Comparis on with th e traditi onal design. - Iteration loop t o ma tch t he p erformanc e of the tradition al design. - Final N triang le o ptimiz ed critical section mod el. The triangles in w hich the str ucture is f ormed are the followi ng: Figure 2. Base triangle of the structure , in purple the wi dth of the beam and in black its height. Several examp les of s imilar f unction ing structures can be fou nd in the references such as the Latt ice structure of a s atellite desi gned by ATG Europe [4]. Once the crit ical optim ized s ection design is obtained the lattice s tructur e will be extende d to the whole rocket to obtain the opt imized rocket design. Add itionally, a thin s kin wa ll jo ined to t he lattice s tructure o n its exterior will be designed to facilitate the hand- layup of the composite material. 3.4.3. Analys is methodol ogy The an alysis is conducte d using Beta Cae Systems A nsa [ 5] as a pre- processor, MSC Nastran [ 6] as a solver and Beta C ae S ystems Meta [7] as a post -process or. Two s ets of analysis will be conducted for t he designs: - Analys is for the c ritica l s ection and optimization of the critical section . - Analys is for the gen eral traditional rocket design and the optimized rocket design. The differe nt analysis un der which both roc ket designs will be su bmitted a re: - Strength an alysis: I n whic h the sta t ic - strength failure mechanism is simulated. - Modal an alysis: I n w hich the dy namic failure mecha nism is simul ate d. - Linear buck ling: To s imulate part of t he buckling failure m echanism . - Non-L inear buckl ing: To s imulate t he non -linear part of th e b uckling failure mechanism. 74 DOI: 10.5821/conference-9788419184405.014 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 4 of 6 For the optimized design to be cons idered usable all t he analyses res ults must be on par with t he trad itional ones, w hich will be used as a target for the perform anc e of the o ptimized structure. Moreover, a loc al d eformation will be introduce d into both critical section m odels to unders tand the structural behaviour in front of possib le irregularities in the hand l ay -up or manufacturing proc ess , th is defor mation will be induced into th e m odel d isplacing the mes h elements. 3.5. Mater ials Th ere are t wo types of m aterials used in this design. 3.5.1. Comp osite materia ls The c omposite materials used in th is ana lysis are a glass fibre and ep oxy composite. F or its modelling the r ule of m ixtur es [8] is applied. 𝐸 𝑐 = 𝑓 𝐸 𝑓 + (1 − 𝑓 )𝐸 𝑚 (1) Where: 𝑓 = 𝑉 𝑓 𝑉 𝑓 +𝑉 𝑚 (2) In E q. 2. 𝑉 𝑓 an d 𝑉 𝑚 are the volume fraction of fibre and matrix respectively. In Eq. 1. The Young Modulus is calcu lated using the Youn g modulus of both material s and the volume fraction 𝑓 of Eq . 2. In a similar way the density , compressib le and tensile strength and poisso n number are also ca lculate d. The g lass fi bre us ed by UP CSP is a E-g lass V- twill of 1 65 grams per square meter [9] and t he Epoxy resin for hand- layup laminates [1 0 ]. Th e volume fraction used for the de sign is of 67% of fibre and 33% of matrix. 3.5.2. Other materials For the trad itional d esign the other mat eria ls to be modelled are: - Alumini um 3 003 with i ts mechan ical properties [1 1 ]. - PA12 wit h its mec hanical properties provided by HP (Hewlett -Pack ard) [1 2 ]. - PLA, use d for com mon 3D print ing [1 3 ]. 4. Results and Discussion The res ults w ill comprise of the most relevant results and comparisons betwee n th e following analysis: - Tradition al two-layere d critical section and d ifferent N tria ngle optimized critical s ections to o btai n the best optimized critical sec tion. - General compar ison between the traditional and optimized final cr itical sections. - 4 mm de ep local d eforma tion a t half length o f the c ritica l s ection between both cases. - Tradit ional design rocket and op timized design rock et lin ear buc kling , non- linear buckling, modal ana lysis, static analysis, and masses com parison. The opt imization process was set with a targ et critical linea l buck ling load of 30 K N, which corresponds to the critical load of the traditional de sign for tw o glass fibr e layers (Factor of security of 10 over t he desi gn load) . When comparing the results to the tra ditional section for a linear buck ling analys is is obtained: Figure 3. Comparison between the two-layers traditional design and the optimization process of the critical section. For the critical sec tion in F igure 2 the optimization process shows a reduction of mass maintaining t he s ame critical l oad ending up o n the 24 -triangle confi guration with a total mass o f 0.32 Kg wh ich will be th e u sed configuratio n for the general optimized rocket . 20000 22000 24000 26000 28000 30000 32000 34000 0 0.2 0.4 0.6 0.8 1 Criti cal load (N) Weight (k g) Traditional and Optimized critical sections 75 DOI: 10.5821/conference-9788419184405.014 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 5 of 6 Figure 4. N= 24 triangle con figurations for the optimized design. 4.1.1. Tr aditional and opt imized critical section compar ison For both the traditional t wo-l ayer design an d the 24 triangles o ptimized d esign are comp ared. Table 1. Comparison between final optimized critical section and two-layer traditional critical section T (mm) Triangles (Width x height , mm) Mass (Kg) Max. Lineal Load (N ) Traditional 0.50 - 0.17 3.18E+04 Optimized 0.25 3.1x1 0.32 3.03E+04 4.1.2. Global a nd local d eformatio ns The 4 mm deform ation is induced in th e mode l at h alf l ength of the cr itical secti on displac ing mesh elements: Figure 5. Displaced elements on the mesh with a depth of 4 mm. For both cas es a non- linea l buckling analysis is launched obtai ning: Table 2. Comparison between Traditional and Optimized critical sections with a 4 mm deep deformation under non-linear buckling analysis. Model Max. Non-linea l load (N ) Traditional Cr it. Se c t. 13200 Opt. Crit. Se c t. 17400 4.2. General rocket mode l The tw o-layer traditiona l d esign rocket and a N=24 Optimized design are compared und er several analysis. Figure 6. CAD model of the optimized rocket design 4.2.1. Linear b uckling analys is Table 3. Comparison between traditio nal and optimized rocket designs under linear buckling analysis. Traditional design Optimized design BF (Buc k ling factor) 6,744 13,076 4.2.2. Non-L inear buckl ing analysis Table 4. Comparison between traditional and optimized rocket designs under non -linear buckling analysis. Traditional design Optimized design Max. V on Misses stress (MPa) 11.9 0. 7 Max. Disp. (mm) 0.2431 0.0121 4.2.3. Modal a nalysis Table 5. Comparison between traditional and optimized rocket designs under modal analysis. Traditional design Optimized design First mode (Hz) 50 .00 32.63 4.2.4. Static an alysis Table 6. Comparison between traditional and optimized rocket designs under static analysis. Traditional design Optimized design Max. Von Misses stress (MPa) 25.7 21 .0 Max. Disp. (mm) 0.3428 0.3276 4.2.5. Mass es Table 7. Comparison between traditional and optimized rocket designs masses. Traditional design Optimized design Total mass ( K g) 11.13 11.96 5. Conclusions 76 DOI: 10.5821/conference-9788419184405.014 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 6 of 6 There are sev eral sets of co nclusions which c an be extract ed fr om t he de sign of the r ocket discussed in th is paper . The optimize d critical s ecti on did no t reach the performance of the traditio nal one. Weighting more and making it unfeas ible t o reach due to the low Young m odulus of the P A12. T he optimized design how ev er is b etter at withstanding loca l deformations, making it less prone to fai lure under irregularities even though that both des igns struggl e to withstan d them as expected. From both fi nal r ocket designs severa l po ints must be raised. F irst the opti mized rock et behaves w ith a much higher BF than the traditional on e, this could be exp lained d ue to the increased th ickness of the w al l because of the beams of PA12. The non-line ar buck ling an alysis results are not conclusive enough to extract s ignificant conclusions. However, bot h d esigns withsta nd the maximum load. The modal analysis show s a variation in the values. These va lues will be used for th e UPCSP team t o ensure that no excitation frequency matches the first mode of the des ign. The s tatic a nalysis is s imilar in bo th des igns, showing th at both c ould wi thstand t he m axim um loads. Addition ally, the optimized de s ign h as lower deformat ions. Finally, the mas s differenc e is greatly red uced in the context of the whole rock et, making it almost similar for both desi gns. Besides the a nalys is the conclusions c an be extended t o the Ares mission inside the UPCSP. It must be co nsidered that several manufacturing issues arise from the hand -lay up of th e composite mat erial. The already existin g strength of the skeleton of the optimized desig n creates an easier wor k env ironment. It is not possible to h and- layup one sing l e layer of g lass fibre properly, thus making al l designs oversized. The a dditive manufacturing approach a llows for complex geometries to a pp ear in t he design. When updating t he optimized rocket w ith t he interior interf aces for the pay load, electronics , etc. the add itive ma nufactu ring a llows for m uch convenient solutions. A stan dardized manufacturing proc edure allow t he rock et to reach higher q uality s tandar ds than hand made parts, which increase the reliability a nd safety of the mission. References [1] UPC Space Program. V isited 1 8 Mar. 2022, from https://upcpr ogram.s pace/ [2] European Rock etry Cha llenge. Visited 18 Mar. 2022, from https://euroc.pt/ [3 ] UPC Escola S uperior d’Enginyeries Industrial, A eroespacia l i Audiovisual d e Terrassa . Visited 1 8 Mar. 2022, fro m https://eseiaat.u pc.edu/en [4] ATG Europe. Visited 1 8 Mar. 2022, from https://www.at g-euro pe.com/solutions / [5] Beta CAE systems ANS A. V isited 18 Mar. 20 22, fr om https ://www.beta- cae.com/ans a.htm [6] MSC Nastran, Visite d 18 Mar. 2022, https://www.msc software.c om/fr/product/ msc-nastr an [ 7] Beta CAE s ystems META. V isited 1 8 Mar. 20 22, fr om https ://www.beta- cae.com/meta .htm [8] Science Direct. Visited 1 8 Mar. 202 2, from https://www.sc iencedirect.c om/topics/en gineering/rule - of -m ixture-equat i on [9] V-Twill 165 Gr S ARGA. Visited 18 Mar. 2022, from https://www.resin eco.com/e s/fibras - de - vidrio-o-carbo no/tejid os-s iliones/v-twi ll- 165 - gr -s arga-100cm. html [10] Resina Epoxi. Visited 18 Mar. 2022, from https://www.resin eco.com/e s/resina - epoxi/resina-e poxi-est anda r/ [11] Aluminium 3003. Visited 18 Mar. 2022, from https://www.a alco.co.uk/dat asheets/Alu minium-Alloy- 3003-0- Sheet _59.ashx [12] HP 3D pri nting ma ter ials. Visited 18 Mar. 202 from https://www8. hp.com/h201 95/v2/GetPD F.aspx/4AA7- 7085EE W.pdf [13] What is PLA? Visite d 1 8 M ar. 2022 from https://www.tw i-globa l.com/ technical- knowledge/faqs/w hat- is -pla#Properti es 77 DOI: 10.5821/conference-9788419184405.014 4 th Symposium on Space Educational Activ ities Barcelona, April 2022 Page 1 of 6 A n i n v e s t i g a t i o n i n t o c o l d we l d a d h e s i o n f o r s p a c e c r a f t r e p a i r a f t e r a s p a c e d e b r i s i m p a c t u s i n g s p a c e e d u c a t i o n b a s e d s u b - o r b i t a l s o u n d i n g r o c k e t p l a t f o r m . Mark Wylie 1 , Leonardo B arilaro 2 __________________________________________________________________________ A bstr act It has b een observed th at sim ilar m etall ic m ateri als, when in con tact and undergo ing relative displacem ents, c an fuse or weld. In s tandard atm ospheric conditions it is not com m on but in th e spac e environment the inabilit y of the surf ace interf aces to re -oxide after abras ive contact is hindered, atom ic diffusion of the m etal occurs, and this can lead t o fusion. Oscillator y motion and Hert zian c ontact stress between th e two surf aces pla y s a m ajo r role in th e stre ngth of the c old welded joint. It has b een sho wn that the acti on of a l ow f retting load can a lm ost double the adhesi on forc e under cy c lic loading e ven in terrestrial a tm ospheric condi tions. In space, c old w el ding was first i dentified in th e 1 9 60 ’s as an adverse reaction . It has been at tributed to anom alies and failures of deplo yable m ec hanisms. Other research has allude d t o the potential of this ph enom ena for use in s pacecraft repair in spac e. Examples where this m ay hold pr om ise is r epair of a spacecra ft hull breach af ter hyperveloc ity im pacts due to m icro m eteoroids or orbital debris. T his research propos es an investig ation into co ld welding for use in spacecraf t hull r epa ir. The research intends to qualif y an exp erim ental apparatus to TRL 4 using a sub- orbital sound ing rock et platform. A j oint research eff ort bet ween the Aer ospace, Me chanica l and Electronic Departm ent at I.T . Carlow, Ire land , th e D epartm ent of Aviation at Malta College of Arts, Science, and Tec hnolog y, Malta is under wa y. The proj ect aim s at developing a te st apparatus to appl y a num ber of custom patch es to sim ulated h yperveloc ity spacecraf t h ull breach e s and investigat e the adhesion properti es during re- entr y for a range of mec hanical application conditions. A num ber of cham bers m ay be tes ted and m onitored using pres sure transducers . After Phase 1 ( terrestrial developm ent and v alidation using a vacuum cham ber ) , there will b e an ap plication to educ ation based space programm es such as the one offered by the European Space Agenc y (R EXUS). T he core of the activit y will be the design an d testin g of the experim ental pa yload, sim ulating hull breach es , de ploy m ent the re pair patc h a nd m onitor ing of its perf orm ance duri ng re -entr y ( Phase 2). T he re covery of the pa yload will allow further m etallurgical analysis of the cold welded joint (Phase 3). A conc eptual 3-D m odel of the payload has been developed and is present ed h ere. T he data acquired from the sub- orbital flight experim ent will tes t the v alidit y of the h y p othesis f or us e of co ld welding for spacec raf t hul l repair b ut wi ll also detail the deve lopment and im plementation of m ock h y pervelocit y im pacts to rock et skin f or the purposes of s im ulating hull breac hes in t he space en vironm en t. Key w ords Cold w elding adhesion, Hy pervelocity impacts, Space debris, Spacec r aft repair, S ub -orbital flight __________________________________________________________________________ 1 m ark.wylie@itcarlo w.ie . In stitute of T echnolog y Carlow, Co Carlo w, Ireland . 2 leonardo.bar ilaro@m cast.edu.m t . The Malta College of Arts, Science & T echnolog y, Malta . 84 DOI: 10.5821/conference-9788419184405.016 4 th Symposium on Space Educational Activ ities Barcelona, April 2022 Page 2 of 6 Acronyms/ Abbreviations CPU Central Process ing U nit DRAMA De bris Risk Assess ment and Mitigation Analysis EM Engineering Model ESA European Space Agency EVA Extra V ehicular Activit y FM Flight Model HGA High Gain Antenna HVI Hyperv elocity impact ISS Internat ional Space St ation LEO Low Earth O rbit LGG Light-Gas Gun LVDT Linear Variable D ifferential Trans former MASTER Meteoroid And Space de bris Terrestrial Enviro nment Ref erence MCAST M alta Co llege of Arts, Scienc e and Technology MRS Mini Researc h Modul e MMOD Microme teoroids a nd Orbital D ebris NASA National Aeronautics a nd S pace Administration ODEM Orbita l Debris Eng ineering Mode ls RSC Rock et and Space Co rporation SSEA Symposium on Space Educationa l Activities 1. Introduction Orbital artificial habitat sat ellites such as the International Space St ation (ISS) ha ve experienced loss of atm osphere due to perforation of the spacec raft hull. T his can occ ur from engi n eering failures , manufacturing defects or Hy perve locit y Im pacts (HVIs) from space debris and m icr ometeoroids [1] . T he frequenc y of the s pace de bris impacts c an be predicted us ing Orbit al Debris Engin eering Models (ODEM curr ently v 3.1) . T he Metroi d impac t f lux can be es timated us ing N ASAs ODPO SSP-3 0425 spec if ication or Europea n Space Age nc y ’s (ES As) Meteoroid And Space debris Terr estrial En vironm ent Reference (MASTER- 8) and DRAMA (Debr is Risk Assessm ent and Mitigat ion An al y s is) [2 ]. One estim ation based on earl y m odels predict that in a 30 - year period m ore than 35,000 secon dar y debris particle im pacts will occ ur to the ISS and will be at energ y l evels high enough to perf orate the solar arra y s [ 1 ]. By the e nd of 2020, t he IS S h as carried out 26 collision avoida nce m ano euvres to es cape impac t wi th space debris [3]. If a collision is unavoidable , the ISS is equipped with a bumper structure k nown as a W hipple/Advanced Stuffed W hipple plate and this is designed t o absorb the impact energ y . Ho wever, secondar y ejecta and collis ion with u nprotected areas can , and do, lead to perforatio n of the ISS hu ll. If there is a hull perf oration, the I SS benef its from its Lo w Earth Orbit (LEO) and ease of ac cess to resuppl y an y l ost oxygen . Lo nger m anned m issions, also suscep tible to hull perf orations, do not ha ve t his option a nd it is a necess ary precaution to consider h ow hulls would be repaired in s pace. There is a paucity of detailed inform ation in the l iterat ure on how these leaks/perf orations are repaired and no standards pu blished but rec ently a descr iption of a s uccessf ul repair of 2.0 m m diameter hole in the S oyuz cre w vehicle which was d ock ed to the Mini Res earch Mo dule ( MRM-1) or Ras svet m odule was release d [4]. It was stated that th e perforation was repaired by usi ng a m edical gauze soak ed in epox y [5]. T he ad hes ive is k nown as Germ etall-1 and packaged as the GERMET IC leak repair k it. T his repair k it includes G erm etall-1 and Anaterm -1u sealant [6] . T he m ost recent loss in atm osp here was identified in the Z ve zda S ervice Modu le i n 20 20. A 2 2 m m l ong crack w as detected i n th e m odule. It was reporte d that the l eak was causing a pressure drop o f 1 mm of m ercur y ever y 8 hours [ 7]. The cr ack was repaired using an un disclosed sealant. It is obvious that ther e is a consc ious effort towa rds f inding a viab le solution. It is proposed to investigate the intentional cold welding of metals for spacecraf t hull repair during a sub -orb ital flight and m onitor the perform ance of s uch repair during re -entr y. This will also invol ve characteris ing and replicating perforations from HVIs. T he aim of this project is to us e an educa tion-base d sounding rock et platform and student team to investigate this phenom enon . T he g oal is to form a pan-E uropean collaboration between third-level i nstitutes and a ward an MSc in Space Systems Engin eering. Project Te am Lead, Materials Eng ineer, Me chanical E ngineer, Aerospace Engi neer and Electronics / Comm unications En gineer are some of the student positions required . 5-10 team m em bers are require d. W ith th at s aid, th ere are bot h educational and technical objectives for the proposed programm e. T his includes the identification of educat iona l space -b ased opportunities through pro gram me outreach. Recruitm ent of a student t eam and appl ication to an educ ation-bas ed sounding rock et 85 DOI: 10.5821/conference-9788419184405.016 4 th Symposium on Space Educational Activ ities Barcelona, April 2022 Page 3 of 6 programm e. As part of the t echnical o bjectives , an En gineering Model (E M) (Ph ase 1) a long with HVIs perforations w ill be de veloped f or terrestrial experim entation and validat ion. It is envisaged that the experim ent s w i ll exam ine several material candidates, surf ace f inishes and a range of impact forces and interactions (fretting and gallin g). The Flight M odel (FM) (Phase 2) w i ll re -des ign th is experim ental set up within the c onfines of a sounding rocket m odul e . It will re quire t he high vac uum conditions , re - entry press urisation and accelerat ion forc es/temperatures to validate th e experim ents. T he m icro-gravity en vironm ent in this phase ma y also pla y a role i n the e volution of the joint a dhesion. The experim ent will in troduce m ock hull per forations and the experim ent w ill operate autonom ous ly durin g the f light prof ile. Further m etallurg ical anal ysi s of the retrieved sam ples wi ll f orm Phase 3 of this research. 2. HVIs and Co ld Weld A d hesion 2.1. HVI effects In hypervel ocit y impacts, the projec tile velocit y exceeds the speed of sound within the t arget m aterial. T he r esult ing shock wave tha t propagates across the m aterial is ref lected b y the surfac es of the target, and reverses its direction of travel. The superim position of progressing and reflected waves c an lead to local stres s levels that exceed the m aterial's strength, thus caus ing cr acks and/or the separation of spalls at s ignificant velocities . W ith decreasing target thick ness, the effects range f rom cratering, via i nternal cracks , to spal l detachm ent, and finally to clear ho le perforations. It has been sho wn that M MOD impac ts on spacecraf t, accordin g to the debris’ dimensions c an generate [ 8] :  Sm all s urfac e pits d ue to m icrometre - size im pactors;  Clear ho le penetrati ons f or m illim etre- size objects ;  Mission-critical dam age f or projectiles larger than 1 cm An y impact of a 10 cm catalogue object on a spacecraf t or orbit al stage will m os t likely im ply a catastrophic disintegratio n of the target. T his destructive energy is a c onsequenc e of high impac t velocities. The eff ects of hypervelocit y impac ts are a f unct ion of projectile and target m aterial, im pact velocity, i n cident angle and the m ass and shape of the proj ectile. At lo w velocities, plastic def orm ation norm ally prevai ls. W ith increasing velocities, the impactor will leave a crater on th e target. Be yond 4 km /s , depending on the m aterial s , an im pact will lead to a c om plete break - up and m elting of the projectile, and an ejection of c rater m aterial to a depth of typically two to f ive tim es the diameter of the projec tile. Usua lly when the impact risk from m eteoroids and orbita l d ebris is assessed the m ain concern i s usu ally struc tural dam age. In this context, the prop osed research targe ts the pre liminar y assessm ent of a rep air to a dam aged spacecraf t hull shields. For th is purpose, a rang e of m ock hull perforati on configurations will be evalu ated and tested. An exam ple perforati on ho le cr eated b y a n Al um inium sphere proj ectile of 2.3 mm diameter at a speed of 4.8 k m/ s is sh o wn in Figure 1 [ 9 ]. Figure 1 . HVI im pact exa mple o n an Alum ini u m plate. 2.2. Cold we ld adhes ion Cold welding is the f usion of tw o m etals at low tem perature. T heoretic ally, adhesion of two m etal samples of the same m aterial wi ll occur in contact prov iding the surf aces were s m ooth (micros copic scale), free from contam inants and the cr ystal lattice of th e opposing s urfac es have the sam e orientation [ 10 ]. There are two schools of thou ght o n the m echanisms behind this phenom ena an d the y ar e based on the film theor y and energ y barr ier t heor y (m is m atch of cr y sta l lattice and rec rystalli zation theor y ). In space, th e a bsence of atm o s phere pro vides necessar y c onditions favourable f or cold weld adhesion. Furtherm ore, evap oration of lubricants in high vacuum and i ntim ate contact of m etal, caus ing disru ption of the ox ide fi lm w i ll further promote th is f usion. In 1966 N ASA published a s tate- of - the -art survey in the f ield of m etal- to -metal a dhes ion or cold weldin g i n space. T his in vestigation exam ined bot h positive and n egati ve eff ects of c old welding in space citing that it ma y be used som eday to fabricate or re pair structure s in space [ 10 ]. 86 DOI: 10.5821/conference-9788419184405.016 4 th Symposium on Space Educational Activ ities Barcelona, April 2022 Page 4 of 6 This was f ollowed i n 1969, when NASA i nitiated a col d welding program to determ ine the pro per test environm ent for qualif ying spacecraf t m echanisms. T his researc h investigated the eff ects of c y cles, and lubr icated versus non - lubricated contact. In 1989, it was proffered that cold welding was sho wn t o be a c redible caus e of the fai lure of the Galileo High Ga in Antenna (HGA) to de ploy [ 11 ]. T he bond strength of cold welding in high vacuum has been s hown to be significant, at least an adhesion s trength equal to the load app lied [ 12 ]. Adhesion forces in the vicinity of 1 0s of Newto ns are reported and, i n certain con ditions, as high as 100 N under h igh vacuum launc h environm ent using silver m ati ng pairs [ 13 ]. Other sof t m etals, such as Indi um , are excellent candidates for deliberate fusion as the y have bee n shown to readil y f use in atm ospheric conditions [ 14 ]. In general, a long with m etal surfac e c onditions, the adhesion forc e is a f unction of the rel ative m otion an d m agnitude of the applie d c ontact forc e. In a study carrie d out b y ESA in 2009 on the eff ects of f retting and m etal ad h e sion, the maximum adhesion forc e (9.5 N) was found to be 2.5 times the applied load (4 N) [ 15 ]. 3. Operational framew ork In Novem ber 2021, I nstitute of Technolog y Carlow, Ire land, initiated a collabor ation wi th the Malta Co llege of Arts, Sc ienc e, and T echno logy (MCAST ), which i s c urrentl y developing th e f irst hypervelocit y impact facility of Malta . This joint research eff ort aim s at attr acting a nd invo lving post an d un dergraduate gr adua te stud ents to a space based project while boost ing the competences of these res earch centres . The two Institut ions a lso initiat ed a collaboration w it h Luleå Universit y of Technolog y, in Sweden. The focus is on stud y ing the p ayload integrat ion of the pre viousl y desc ribed experiment on a rocket for a sub-orb ital f light. The space researc h centre of this Un iversit y has world- class facilities and part ners w it h Esrange , a rocket range and research centre located near Kirun a in northern Sweden. C urre ntly a Mem orandum of Understan ding is being f inalis ed. 4. Results 4.1. Preliminary desi gn A conceptual design of an experimental la yout has be gun . This includes four Alum inum alloy cham bers (7075-T 651), her m itically sea led and m ounted to th e roc k et sk in at the location of a sim ulated hull breach. Spac e qualified bondi ng age nt, such as Kry ptos m a y be used to f orm the seal. E ach unit will in vestigate a s et of experim ental param eters establishe d through Phase 1 testing . This m ay include, material type, surf ace f inish and s urfac e contac t conditions . At ap ogee t he experim ent will comm ence. Signals f rom ei ther gro und s tation (SOD/SOE) or t im ers will initiate the exp erim ent after Yo-Yo sta bilisation . A breac h in the rock et skin is introduce d to eac h chamber and the m aterial sam ples will be a ctuated b y s tepper m otors or piezoelectric actuator s. T he perform ance of the seal ed cham ber will be m onitored usi ng welde d s tainless ste el tem perature c om pensated differential pressure transducers located in eac h cham ber a nd will be m onitored dur ing r e-ent r y. Som e cham bers m ay be press urized prior to re-entry t o examine the joint integrit y in space ( aga i nst a vacuum alone). A P C104 em bedded CP U will be used to acqu ire the data. It w ill b e s tored locally, and an onboard Service Module (SM) and transm itter wil l b e us ed to tr ansit live data to ground stat ion (sensors and housek eeping) . Load cells or Li near Variab le D iff erential Tr ans f orm er ( LV DT ) may be used to ver if y the position of the sea ling patch and th e a pplied and reaction f orces. Video data m ay also b e acquired a nd st ored local ly as a m eans of anomal y detection. A pr elim ina ry outline and design of the experim ent h as been created. A potential configuration f or multiple test cham bers is offered but not f ixed. It is intended for use a s a guide or tem plate for s tudents to develop further into a proposal for a sp ace - based e ducational rese arc h program . T he preliminar y desi gn of the t est r ig is shown in Figure 2. T his exp erim ent is designed within 356 m m diam eter and 237.5 mm in height , a standard REXU S so unding rock et m odule. Expected m as s (exc luding rock et sk in and baseplate) is less than 4.5 k g. 87 DOI: 10.5821/conference-9788419184405.016 4 th Symposium on Space Educational Activ ities Barcelona, April 2022 Page 5 of 6 Figure 2 . Conceptual design of sounding rocket experiment (mm). This paper a lso details the basis of the t echnical objectives required for the s tudent experim ent. The ge neral t hem e of the research is presented but the intention is that the student t eam will develop this proj ect in more deta il. 5. Conclusions This publication form s the f irst c ollaborative eff ort towards ach ievin g the academic objectives. It is designed as a n impetus f or students to develop t his program m e. T here are a number of funded student positions availab le. Expressions of interest c an be emailed to either of the authors before Novem ber 1 st 2022. T his eff ort was conceived as a m eans to com bine expertise and resourc es f rom multiple t hird- level institutes with l imited space flight heri tage , to bolster th eir sp ace resea rch capab ilitie s and to prom ote European co llaborations . Acknow ledgements The authors would l ike to thank I nstitute of Tec hnology Car lo w and M alta Col lege of Arts, Science & T echno logy for their support with this research. W e would also lik e to thank LT U f or providing the ir guidance a nd expert ise. References [1] W .P Schonberg, Charac terizin g Secondar y Debris Ejecta, Intern ationa l Journal of Impact Engineering , 26 (2001) 713 -724. [2] S.Lemm ens, V . Braun, B . Bo nvois in . Space Debris Mitigation: Methods (and implem entation) MA STER8 , DRAMA3 & ESTIMATE , European Space Agency , 2008 . [3] ESA’s Space Debris Office , F AQ. https://www.esa. int/Safet y_Securit y/Spa ce_Debris/FAQ_Fr equentl y_ask ed_ques tions , 2021. [4] C . Geb hardt, NA SAspacef light.com . https://www.n asaspacefligh t.com /2018/0 8/soyuz-statio n-leak - no -thr eat-repairs - continue/ , 20 18. [5] H. W eiteri ng , “ Astronauts W or k to Seal Air L eak on Space S tation. Here's How ” . N. https:// www.space.com , 2018 . [6] ISS On-Orbit Status , https://www.n asa.gov/direct orates/heo/r eports/iss_rep orts/2012/1 1162012. htm l , 2012 . [7] M . W all, “ Small air leak on space station traced to R uss ian ser vice m odule” . https://www.space.c om /international - space-station -air-leak - russian-m odule , 2020 . [8] L . Barilaro, “Measurem ent t echniques for assessing and reducing the risk posed b y Microm eteoroid and O rbit al D ebris t o Space vehic les”. PhD T hesis , 2012. [9] L. Barilaro., C. Fa lsetti, L. Olivieri., C. Giacom uzzo, A. Francesconi, P. Be ard, R. Cam illeri: “ A concept ual stu dy to characterize properti es of space debris from h y p ervelocit y im pacts through T hin Film Heat F lux Gauges ” . IE E MetroAeroSpace (Na poli, Ital y ) , June 2021 . [ 10 ] H. Pattee , R. Monroe, “Adhesion in Space Environm ent” . R esearch Branc h US Army Mi ssile Command , 1966. [ 11 ] J . Ta y l or, K .M C heung, and D. Seo, , Deep Space Comm uni cations, Chapter 88 DOI: 10.5821/conference-9788419184405.016 4 th Symposium on Space Educational Activ ities Barcelona, April 2022 Page 6 of 6 4- Galileo Te lecomm unications , W i ley, 2016. [ 12 ] H. Conrad, L. Rice , “T he cohesion of previousl y frac tured FC C m etals in ultrahigh vacuum ” , Metallurgica l Transactions , pp. 3019 -302 9, 1970. [ 13 ] A . Mers tallinger, R .H olzbauer and N . Bams ey.” Cold W eldi n g in Hold Down Points of Space Mec hani sm s Due to Fretting W hen Om itting G rease ”. Proceedings of the Institution of Mechanical E ngineers , Part J: Journal of Engineering Tribology , Vol um e 222 ( 8): 10, 2008. [ 14 ] A.C Moore, D. Tabor, “ Som e Mechan ical and Adhesion Properties of Ind ium ” , British Journa l of Appl ied Physics 3(9):299, 2002. [ 15 ] A. M erstallinger, M. Sales, E. Semerad and B.D. D unn. “Assessm ent of Cold W elding between Separ able Contac t Surfaces due to Im pact and F retting under Vacuum ”. ESA STM- 279 , 2009. 89 DOI: 10.5821/conference-9788419184405.016 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 1 of 6 S u p p o r t i n g a n I S S e x p e r i m e n t a s P h D s t u d e n t s : a c a s e s t u d y o f t h e P A R T I C L E V I B R A T I O N p r o j e c t Georgie Crewdso n 1 * , Alessi o Boaro 1 , Monica Kerr 1 , Ma rcello Lappa 1 __________________________________________________________________________ Abstract This paper provides an insi ght into t he involvem ent of t wo PhD students in the PARTICLE VIBRATIO N project, a mu ltiphase fluid experimen t , a lso know n as, “T hermovibrat ionally -driven P article s elf- Assembly an d Order ing mechan isms in L ow grAvity” ( T-PAOLA ) to be launch ed on th e Intern ational Space Station by the end of 2022. The proj ect aims to id entify self- organizatio n phenomena in dispersed phase flows when v ibrat ions are applied to th e system. It will therefore underpin the development of new contactless particle m anip ul ations and materials proce ssing strategies. In this short paper, the work of two Ph D c andidates, working within the T -PAOL A proj ect framework, is discussed. In doing so, t he various research activit ies undertaken are highlighte d, bo th experimental a nd nu me rical, as is the peripheral or supporting research being u ndertak en by both s tudents in order t o expand the sc ope of the project and identify new lines of enquiry regardi ng conv ection - based contro l mechan isms. Keywords Microgravity , Thermovibrat ional co nv ec tion, Part icle ag gregation , ISS experi ment , T-PAOL A project _________________________________________________________________________ 1 Department of Mechanica l and Aerosp ace Eng ineering, Univers ity of Strathc lyde , Glasgow , UK * Correspondi ng author: ge orgie.crewdson @strath.ac .uk 90 DOI: 10.5821/conference-9788419184405.017 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 2 of 6 Acronyms/Abbr eviations E SA European Space Agenc y E-USOC Spa nish User Su pport an d Operations Centre MSG Microgravity Sc ienc e Glove box ISS International Space Station SODI Selectable O ptical Diagnos tic Instrument T-PAOLA Thermovibrational ly- driven Partic le self-Assembly a nd Order ing mechanisms in L ow gr Avity TVC Thermov ibrational C onvection 1. Introduction Working on a sp ac e e x peri ment to be launched on the I nternation al S pace Station (ISS) is the dream of many mechan ical and a erospace engineering stude nts. These opportunities are however d ifficult to come- by as the leve l of expertise required to undert ake such projects i s significant, and often bey ond the sk i lls of postgraduate students. Althou gh sig nificant efforts have been made by organizat ions such as E SA Academy to make altered gravity and space platforms more acces sible to stu dents, contributing effectively to projects of such a kind and s cale rem ains a ch allenge. Th e T- PAOLA project (Thermov ibrationally -driven Particle self-Assembly and Ordering mechanisms in Low grAvity , the c orresp onding N ASA/ES A opsnom bei ng “Particle Vibration”) , however, has enabled two PhD s tud en ts from th e University of Strathclyde to immers e themselves in a conc rete space experimen t, leading to s ignif icant benef it s for both the students a nd the projec t its elf. In the fol lowing, first the scie ntific context of the ex per im ent [1 ]– [4] , the str ucture of th e researc h team and the other stake holders ( spac e agenc ies and payload dev eloper) are introduced . Then, the specific activit ies undert aken by the stu dents to di rectly support th e project are described, followed by a m ore ge neral presentation of their respective r esearch inter ests and r esults . These align w ith th e general goa ls of any microgravity -related proj ect, na mely, a meaningful extens ion of current state of knowledge thro ugh th e ex ecution of a w ell- defined ser ies of s pace experiment and the definition o f oth er exp erim ents to b e ex ecuted in the future to fill the rema ining gaps ( see e.g. refs [5], [6]) . 2. Scientific objecti ve and t eam 2.1. Scientif ic objective The T -PAOLA project consists of performing multiphase fluid dynamic ex periments onboar d the ISS. These experiments will inv estigate ho w a set of particles dispersed i n a Ne wtonian liquid can accumulate and form well - or dered structur es. Ind eed, o n eart h, th e b ehaviour of particle-fluid mixtures is constrained due to gravity leading to flotati on or sediment ation of the partic les. O nce gr avity is remove d, the dispersed partic les are not forced to separate and exp loring sel f-as sembly pri nciples becomes poss ible . By stu dy ing these surpr ising phenome na un der micro gravity con ditions , T-PAOLA aims to pave th e way to i nnovative applications in chem istry, ph y sics, bi omater ials, inorganic material scien ce and eventually nanotechnolo gies. The flo w th at faci litates t his parti c le aggregati on is known as therm ov ibrationa l c onvection (TVC). This type of c onvection is a varia nt o f standard buoy ancy co nvection wh ere ste ady gravitational acceleratio n is replaced with vibrations (see Fi gure 1). When subjected to TVC, the patterni ng beh aviour of t he flu id becomes dependent on not only the m agnitude of the i mposed temperatur e gradient bu t a lso on the freq uency and am plitud e of the consid ered vibrations and t he direction of t hese with respect to the t emperature gradient Figure 1: Mathematical model for (a) thermogravitational convection and (b) thermovibrational convection. When parti c les are added t o the mix, in microgravity condit ions ( where the only driv i ng force present is due to vibratio ns), many different patterning beh aviours are possibl e when the space of para meters of TVC is explored (frequency and amplitude of th e vibrations ). The properti es of the particles a lso contribute to the struc ture formatio ns, where both the size, density and concen tratio n of particles af fect the fina l s tr uctures . An ex ample of possible pa tt erning co nfi gurations is dep icted in Figure 2 (ad apted fro m Re f [7] ) . 91 DOI: 10.5821/conference-9788419184405.017 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 3 of 6 Figure 2: Example of particle aggregate structures varying in shape due to varying dif ferent thermo-vibrational conditions. To k eep t he ISS experi ment as simp le as possible an d ow ing t o the fact that the proj ect utilises the ex isting ISS hardware Selectable Optical Diag nostics Ins trumen t (SODI) in combination w ith the Micrograv ity Science Glovebox ( MSG), only the v ibrational frequency, amplitude and te mperature difference across the cavity are var ied and the direction of vibratio ns is set in a p erpendicu lar manner to the temperature gradient (as show n in Figure 1 ). However, keeping w ith t he ai m of exp anding the project sc ope, the inv olved PhD s tudents (first and second author of the prese nt paper , hereafter simply referred to as GC and A B , respectively ) have a lso co ns idered situations in which the tem perature gradient has a diff erent orientation and/or the liquid also p osses s es elastic propert ies (non- Newtonian f luids). 2.2. Team co mposition A nota ble asp ect o f the proj ect is the composition of the team responsible for the success ful completion and continuation o f the Particle Vibration project. The team i s composed of two sub- tea ms . The science te am (based at the University of Strathclyde) inc ludes the principa l investigat or (f ourth aut hor, ML), a research associate ( third author , MK ) and the two af oremention ed PhD s tudents . The t eam is responsible for providing the exact scientific requirements for t he series of experiments to be conducted on b oard the ISS an d for expa nding the project sc ope by pushing its bo undaries further. The techn ical team i ncludes the relevant pers onnel of th e compa ny in charge of manufacturing the ex periment hardwar e (QinetiQ), t he ESA project c oordinator, the E SA Payload Integ ra tion Man ager and the User Support and Operations Centre (E -USOC) in charge of commanding remote ly the payload and d evelop ing t he re lated proc edures . In Figure 3 we schem atise the compositio n of both teams. Figure 3 : Composition of the Science an d the Industry team. 3. Discussion 3.1. Projec t activities and team integrat ion In th is section the v arious activit ies undertaken by G C and AB , and direc tly re lated t o t he T-PAOLA space experimen t, are d iscuss ed. 3.1.1. Experi mental ac tivities (G C ) We b egin this secti on with discuss ing the plethora of ex perim ental a ctivities undertaken GC . For brevity we focus on the two mos t relevant tasks . Firstly, GC attend ed a weeklong activity w here Qinet iQ had been contract ed to carry out t he “c ell f illing proced ure”, wh ere t he quartz cells to be used on t he ISS are f illed w ith both th e f luid and the particles . Duri ng the filling procedure, many foresee n (and u nf oreseen) obstacles w here tackled. These obstacles provided an ins ight into the d ifficulty of monitoring and perform ing the high-prec ision tasks required for the s uccess of th e experiment. The second critical experimental procedure to be carried o ut was th e degass ing of the f luid in preparation for the experime nt (shown in F igure 4) , whic h was supervised by MK. The related rationale/c hallenges can be described as fo llows. Under atmos pheric pressur e a smal l a mount of “air” is tr apped in the flu id. W he n the fl uid is placed unde r vac uum, th is air is forced out of the fluid cr eating un wanted air bu bbles in the fluid c ell. Of course, this ca n ma k e any particle formations imposs ible , therefore th e fluid must be p urged of all r esidual air befor e it is inserte d in th e c ell w ith the pa rt icles. Th is ac tivity involves th e us e of both co mpressed gases and liquid nitrogen tha t required GC taking short 92 DOI: 10.5821/conference-9788419184405.017 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 4 of 6 courses, henc e developing her s kill set , as wel l as contributi ng to dev eloping bespoke experimental prot ocols. Figure 4: Nitrogen gas is bu bbled through the ethanol to displace any remaining oxygen. 3.1.2. Data downlink a nd p ost processing (A B) In addition to the fu ndamental ex perimenta l activities, anot her crucial part of t he proj ect h as been the treatment of the experi ment al dat a (signals and images) pr oduc ed i nitially during ground testing . A proper description of t hese aspects requires t he intr oduction of so me details about the contro l parameters of t he experiment ( as deve loped in the fo llowing ) . As stated in the introducti on, TVC arises inside a differentia lly heate d cavity when v ib rations are applied. After selecting the propert ies of the fluid an d t he particles, four other c ontrol parameters r emain, n amely , the tempe rature at the to p and bott om of the cell , the freque ncy of the vibrati ons and their am plitud e. In a ddition , the a pplied temperature has to be var ied sinusoidally in c ertain stages of the ex periment in order to re -disperse t he particle s (after particle structures are fo rmed f or a given combination of the pa ramet ers , i nitial condit ions with a uniform distribut ion of p artic les must be established for th e ex ecution of the next experiment de aling wi th a d ifferent combi nation of them) . In Autumn 2021 gro und te st s were carr ied out by the a forement ioned E-USOC w ith two- fold purpose to 1) assess the consistency of the payload so ftware (exper iment “s cripts”) wi th the specifications provided by the s cientific team and 2) verify the ab ility of the h ardwar e to support ade quately the ranges of temper ature and v ibration al frequenci es specified t hrough such a set of r equirements. Here, t he support of AB w as funda mental. H e developed a r obust a lgorithm capable of automatically check ing the results of t he t ests against the requirements in terms of dura tion of every ste p and a mplitud e and fr equency of bot h vi brations and temperatu re. More over , t he algorithm w as also able to c lassify the pictures recorded d uring e ach run and split them i nto different subgroups accordin g to t he specific step of the experiment in w hich t hey had bee n generated . A s an example, Figu re 5 shows part the algorith m output for a generic run. This procedure reve aled an inconsistency between the image number ing an d the rec orded signals, w hich was ti mely c omm unicated to the E-USOC an d f ixed accordingly. More over, t he processed data proved that the hardware coul d maintain the re quired therm al modulations . a) b) c) Figure 5 : Output of the algorithm. The vertical dashed lines indicate the s ta rt of a new step. a) Frequency and b) Amplitude of the vibrations, and c) temperature of the pr imary cell. 3.2. Expansi on of pro ject s c ope throug h peripheral research We now turn t o the s pecific topics of the students PhD thes es an d show how their activities are contrib uting t o the legacy of the Particle Vibration project not on ly from a technical point of v iew, but a lso in terms of scientific outcomes . 93 DOI: 10.5821/conference-9788419184405.017 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 5 of 5 References [1] BryceTech, “The 2 019 Global Sp ace Economy at a Gla nce,” Oc tober 5, 2020. [2] The Institution of Engineering and Technology, “ Satellite Co mmunicat ions Systems Cours e,” [Online]. Available: https://satcoms.the iet.org/. [3] Systems a nd Netw ork Ltd., “Ess ential Satellite commun ications,” [Online]. Available: https://www.snt.co. uk/traini ng_courses/N etworking/Sate llite_commu nications_co ur se.htm. [4] The Kno w ledge Aca demy, “Satellite Communicati on Tra ining,” [Online]. Available: https://www.th eknowledge academy.c om/ courses/advanced -tec hnologies- courses/satel lite-comm unication -training/. [5] D. M. St einer, Lear ning, Construc tivist Theories of, vo l. 276, 2014, pp. 319 -320. [6] D. C. P hillips, B ehaviorism and Behaviorist Learn ing T heo ries. I n: Seel N.M. (eds) Encycloped ia of the Sciences of Learning, Spr inger, B oston, MA, 2012. [7] Y. Inoue, “ Learning a nd Co gnitive Theory Applied to Educatio n,” College of Education, U niversity of Gu am, 2000. [8] J. Utecht and D. Keller, “Becoming Relevant Again: Applyi ng Connectivism Learning Theory t o Today's Classrooms,” Critical Questions i n E ducatio n, vol. 10, pp. 107-119, 2019. [9] P. A. A lmeida, “ Kolb’s Experientia l Learning The ory Revisi ted,” Advances in Psychology Research, vol. 102, pp. 6 3- 76, 2015. 100 DOI: 10.5821/conference-9788419184405.018 4 th Symposium on Space Educational Activities Barcelona, April 2022 DEAR project: Lunar Dust Surface interactions, Risk and Removal investigations C. Jalba , P . Milev 1 , P . Schulz , A. Pflug 2 , P . Ramm , O. Gusland , I. Ghitiu 1 , R: Jalba 1 , A. 1 2 2bis 3 Magureanu 1 , A. Molenta 1 , A. Pantea 1 , G. Pantea 1 , L. Jalba 1 , S. Özdemir -Fritz , G. Groemer 4 , 4 A. Müller , H. Steininger 5 , D. McKeown , F . Gibson Kiely 6 , J .Hamilton 5 6 1 __________________________________________________________________________ Abstract The DEAR project (Dusty Environment Application Research) investigates the interaction between lunar regolith and surfaces and components relevant for lunar exploration. Based on the TUBS regolith simulant which is representative in chemistry , size and shape properties to Moon soils to study the regolith transport, adhesion and strategies for cleaning. The regolith simulant will be applied to thermal, structural, optical sensor , sealing and other astronautic systems, providing input for requirements, justification and verification. The key applications are split in human space flight regolith investigations, wrinkled surface with random movement and hardware surfaces, flat material defined movement. The paper provides an overview of the DEAR project including a discussion of the first results, in particular vibration, shock and micro-vibration on regolith bearing surfaces. The investigation shall enable better understand the regolith layers interaction and the release mechanism, as well as potential cross contamination and cleaning strategies. The research is complemented by simulation of the regolith motion as parameter surface plasma interactions. The project is funded and supported by the European Space Agency (ESA). DEAR specifically addresses the development and testing of lunar dust removal strategies on optics, mechanisms and human space flight hardware (e.g., space suits). As the Moons regolith is known to be highly abrasive, electrically chargeable, and potentially chemically reactive, lunar dust might reduce the performance of hardware, such as cameras, thermal control surfaces and solar cells. The dust can cause malfunction on seals for on/of f mechanisms or space suits. Of particular interest are risk assessment, avoidance, and cleaning techniques such as the use of electric fields to remove lunar dust from surfaces. Representative dust (e.g., regolith analogues of interesting landing sites) will be used in a dedicated test setup to evaluate risks and ef fects of lunar dust. W e describe designs and methods developed by the DEAR consortium to deal with the regolith-related issues, in particular an electrode design to deflect regolith particles, cleaning of astronautical systems with CO2, design of a robotic arm for the testing within the DEAR chamber , regolith removal via shock, and regolith interaction with cleanroom textiles. Keywords Astronaut space suit, Electrode design, Regolith (lunar dust), Robot arm, Specific cleaning (CO2) ________________________________________________________________________ Microelectronica, Romania, [email protected] 1 Fraunhofer IST , Germany 2 Fraunhofer EMFT , Germany 2bis Gusland Consulting, Norway 3 OeWF , Austria 4 OHB, Germany 5 University College of Dublin, Ireland 6 University of Hawaii 1 Page of 1 6 101 DOI: 10.5821/conference-9788419184405.019 4 th Symposium on Space Educational Activities Barcelona, April 2022 1. Introduction Interest in lunar exploration has regained thrust in recent years around the world. ESA, private industries, and the academic sector strive to explore the Earth ! s satell ite with a m b i t i o u s n e w t e c h n o l o g i e s . T h e h o s t i l e e n v i r o n m e n t o f t h e M o o n , h o w e v e r , i s generally perceived as a serious challenge, in particular the lunar dust. T o minimise its impact on optical surfaces and mechanisms, seals, and in order to reduce operational risks during future lunar missions, the European Space A g e n c y h a s co n t r a c t e d th e DE A R (d u s t y environment application research) consortium to deal with regolith-related issues, catalysing European moon surface exploration missions in the near future. 1.1. Risks posed by Lunar Dust Being highly abrasive, electrically chargeable, and potentially chemically reactive, lunar dust poses a high risk on the performance of hard- ware, such as cameras, thermal control, and solar cells. The dust can cause malfunctions on seals and influence the optical, mechanical and electrical as well as thermal properties of surfaces including space suits. For instance, during the sample processing on the lunar s u r f a c e or in ai r lo c k s , r e l i a b l e s e a l s ar e mandatory . Furthermore, lunar dust is likely to be toxic and therefore needs to be avoided inside the lunar habitats, motivating the work on validated cleaning methods. T est setups shall be used to measure potential performance degradations within controlled dusty loads. A programmable robotic arm is used for repeated lifetime testing and for the mimic of the movement of an astronaut arm. 1.2. Cleaning methods Cleaning is possible due to the avoidance of regolith dust built up or with active cleaning pro ce sse s t o re mo ve t he d us t. P ro tec ti on possibilities and cleaning efficiencies shall be e x p e r i m e n t a l l y e x t r a c t e d . I n p a r t i c u l a r electrode structures creating electric AC fields for dust removal are in first order studied by simulation and test. Another cleaning method by applied vibration and shock is studied as well. The cleaning of astronautic systems is tested with CO 2 cleaning. 2. Discussion 2.1. Optical-Electrode simulation and Electrode breadboard This work includes a simulation of how to re- move dust particles covering optical windows e.g. photographic cameras, image sensors etc., utilising an electrostatic (electrophoretic) force on particles with inhomogeneous electric fields. The implementation of inhomogeneous electric fields is done via structured thin film electrodes, either metal films or transparent indium tin oxide (ITO) on a glass substrate. For si mul at io n o f t he beha vi ou r r eg ar di ng t he electrode, the following simulation codes are used: • The Particle-in-Cell Monte-Carlo (PIC-MC) simulation code developed at IST Fraunhofer , using the distributed, parallel Poisson solver , which is based on the Ga us s -S e id e l a lg o ri th m wit h s uc c es s iv e over relaxation (SOR). • A simulation tool named “P ALADIN”, for modelling the transport of macro-particles of variable sizes that considers particles of sizes ranging from nanometers up to milli- meters, and may include various physical forces such as gravitation, gas friction, ther- mophoresis, charging and decharging, as well as electromagnetic field forces. The combination of these tools allows the computation of the trajectories of a diluted ensemble of non-interacting nanoparticles on electrode structures. For a higher density of particles – as is the case of many dust layers covering a window , different simulation methods such as the Discrete Element Method (DEM) would be needed. 2.1.1. Simulation of electrode structure Our simulation test geometry consists of a ceramic substrate material sized 10x10 mm 2 and a thickness of 1 mm (Fig.1). On the top side, the electrode structure is integrated into the substrate. It consists of metal lines with a thickness of 100 µm and a lateral width of 200 µm. Figure 1. Geometric test structure used in simulation for various electrode designs T wo metal wire systems are connected to the positive and negative output of a voltage source. Page of 2 6 102 DOI: 10.5821/conference-9788419184405.019 4 th Symposium on Space Educational Activities Barcelona, April 2022 T able 1. Basic parameters used for the electric field computation of the test structures The simulation volume for solving the electro- static potential via the Poisson equation com- prises the substrate plus a 10x10x10 mm 3 cube on top of the substrate, which is facing the side with the electrode structure. Th e com p u te d ele c t r ic fi el d , t h e r e s u lt i n g particle trajectories and the dielectrophoretic forces are shown in Fig. 2. For the P ALADIN simulation, particles with a relative dielectric permittivity of ε r = 3.0, mass density of ρ = 3.5 g/ c m³ , a n d h o mo g en e ou s siz e d i st r ib u ti o n between 10 - 500 µm are used. T h e i r s t a r t i n g p o s i t i o n s a r e r a n d o m l y distributed on the substrate surface with the electrode structure. An important result is that on surface areas, where alternating poles are entangled, high electrophoretic forces up to several 100 g occur , allowing for particles to drift away from the electrodes. In contrast, in regions with only one polarity of the electrode structure, the d i e l e c t r o p h o r e t i c f o r c e s a r e s m a l l , a n d particles have the tendency to remain sticking there. 2.2. Astronautic systems. Cleaning with CO 2 This activity is mainly focused on space suit materials but also equipment to be used by the astronauts. Following the “AMADEE-20” Mars analog field campaign in the Israeli Negev desert, a carefully selected crew of analog astronauts were deployed for one month. Figure 2. (1) Electric potential in a cut-plane located 100 μ m a b o v e t h e s u bs t r at e w i t h t h e e l e c t r o de structure; (2) Central cut plane of the electric field showing the inhomogeneous regions in between alt erna= ng poles; (3) P ar =cle trajectories c omputed by P ALADIN; (4) Computed dielectrophore=c forc e in units of the gravita = onal fi eld Parameter Va l u e Low resolution High resolution W afer thickness 1.0 mm Simulation box size 10 * 10 * 1 1 mm 3 Segmentation 4 * 4 * 2 = 32 segments up to 32 CPUs Cell spacing 0.1 mm 0.05 mm Number of cells 1.1 * 10 6 8.8 * 10 6 Electrode voltage ± 1000 V Substrate material Ceramic material ε r = 6.0 Solver Poisson equation; Distributed Gauss-Seidel with SOR Page of 3 6 103 DOI: 10.5821/conference-9788419184405.019 4 th Symposium on Space Educational Activities Barcelona, April 2022 Their work included performing simulated extra -veh icula r act ivity (EV A) – w ith ta sks pertinent also to lunar exploration, such as geosampling activities, maintaining critical hardware infrastructure of surface translation. In total, 61,35 EV A hours were conducted. The spacesuits were representative of what is to be expected for future lunar missions, with a mass of 50 kg, 3 hour so donning time and a complex technical infrastructure for satisfying the needs of a human body , technical and biomedical monitoring and human metabolite management [2] and performing the EV A ’s in a manner pertinent to what is expected during a planetary surface operation [3]. Figure 3. Fiel d work with spacesui t simul ators during the AMADEE-20 expedition in Israel. (Photo courtesy of Florian V oggeneder (OeWF)) The surface textiles of the spacesuit simulators accumulated “regolith simulant” in a realistic fashion and were then transferred to a CO 2 - cleaning facility to investigate the effectiveness of the cleaning workflow . 2.2.1. DEAR T est T extile Selection The outermost layer to be focused upon will be in direct contact with regolith and the physical environment of the Moon. Based upon the parallel ESA project PExT ex where dozens of candidate textiles were investigates, a shortlist of potential candidates was selected based upon the following criteria presented in T able 2: The resistance to dust abrasion, e l e c t r o m a g n e t i c c o m p a t i b i l i t y ( E M C ) a n d discharge protection and dust mitigation were pr io r it ie s for t h e c ho i ce . T h e s el e ct io n i s Inventex F1 120Al, having following properties: (Kevlar ® orthofabric) • T ensile strength 5 times higher than steel • Permanently non-inflammable • The fiber starts to degrade at 420 °C, for short duration can withstand higher temperatures • Panox ® preoxygenated polyacrylnitril fiber with >60% carbon content very high LOI (l i m i t ed ox y g e n i n d e x) of 45 s t a r t s t o segregate graphite above 700°C and as such has a very high thermal resistance • low mechanical strength → Kevlar has been combined T able 2. Selection criteria Several CO2 Cleaning Methods to remove lunar dust from the space suits are being tested, including blast cleaning with super- critical CO2 jets. 2.2.2. Benefits of Cleaning with CO 2 The CO 2 Snow-Jet Cleaning method requires 80% less space than conventional power-wash systems which are water-based. The time which is needed for one cleaning cycle is as well 80% shorter and the costs are reduced by up to 40%. This cleaning method is not adding any excess CO2 impact on the environment because the used CO2 has been re-captured from existing industrial emissions. 2.3. Robotic Arm The objective is to develop a robotic arm testbed for the DEAR chamber . The testbed w i l l b e a b l e t o a r t i c u l a t e i n a n e a s i l y programmable and repeatable manner with/ without the application of lunar regolith, based u p o n a P i n c h e r X 1 5 0 r o b o t i c a r m f r o m I n t e r b o t i x . T h e Pi n c h e r X 1 5 0 R o b o t A r m f e a t u r e s , 5 d e g r e e s o f f r e e d o m u s i n g D Y N A M IX E L X L 4 3 0- W 25 0- T s m ar t s e r v o s motors, with a resolution of 4096 positions per rotation and user definable PID parameters. It allows the following parameters to be logged • Cartesian Coordinate at end ef fecter (m) • Angular Displacement of the joints (rad) • Angular V elocity of the joints (rad/s) • Ef fort produced by joints (Nm) • T emperature of joints (°C) • Present load of the joints (% of maximum torque) • Input V oltage of each joint (V) Withstand Lunar T emperature Withstand and/or reduce Lunar radiation Compatible with lunar vacuum Must sustain pressure- vacuum cycling (?) EMC and discharge protection Resistance to wear by abrasive regolith Bendability (?) Fatigue integrity over the expected suit life Shall not off-gas toxic substances Shall be non-flammable Dust mitigation Impermeability to water and fluids Page of 4 6 104 DOI: 10.5821/conference-9788419184405.019 4 th Symposium on Space Educational Activities Barcelona, April 2022 Figure 4. CAD drawing of PincherX-150 robot arm from Interbotix The PincherX 150 is controlled by a Robotis DYNAMIXEL U2D2 which interfaces with a range of commonly available robotics software such as ROS, Gazebo, Coppella Sim and Move it. It is of interest to measure the maximum payload the arms can reliably perform typical manoeuvers with. The Pincher- X150 is rated for a 50g payload at its end ef fector but can c a r r y l a r ge r m a s se s w h en t h e we i gh t i s distributed over the full length of the arm, as it the case when covered in textile. A series of tests were performed by wrapping the arm in a textile of known mass and measuring the maximum effort in the joints, during an “arm curl” movement repeated 50 time. 2.4. Regolith removal from surfaces using vario us ex tern al fo rces (shock, v ibra tion , magnetic field) One of the first choices to remove unwanted dust is a shock or vibration mechanism. Apart from the ef ficiency of the method, we bear in mind, an example of spatial activities with mechanical shock tasks as, for instance, the crushing station, part of the ExoMars rover , is equipped with a little hammer mechanism. After a drill sample is crushed, the hammer is applied to remove potential powder contamination from the sensitive surfaces prior to the next sample investigation. 2.4.1. Shock testing Measure the displacement of dust applied to a surface by means of mechanical shock. The purpose of the experiment is to quantify the displacement of dust particles as function of the momentum transferred to the system. The control parameter is mass displacement for a well-defined mass, angle, and height of the pendulum (linear momentum transfer). Experimental set-up consists of a pendulum with a rigid arm, a support, a Si wafer with applied regolith on it. The camera was used for recording of experiment. In a rectangular area of 50 x 16 (= 800 mm 2 ), we are placing the five types of particles, that differ by shape and sizes. The chosen particles for the experiment are: NaCl, anhydrous CaSO 4 , CaSO 4 *2H 2 O, T alcum powder , regolith simulant TUBS-M. Figure 5. Experimental setup The set-up has been improved in the following way: • The arm of pendulum is rigid and without torsion • The area of particle covering is well defined by using a “window” of sieving the powder; • The applied concussive force is automatic, excluding direct human intervention. As control parameter , the mass of particles is measured, that has crossed the line on the side of the pendulum, by carefully removing the particles with fine brush into a watch glass, then measuring its weight. The control of the accuracy of that operation is done by weighting the remaining powder inside the initial area and deciding whether the difference to the original amount is within the limits of error tolerance. Experimental results are presented in T able 3. T able 3. Experimental results for dust removal with identical shocks, and distribution of dust on surface Particles type /% of displaced powder Exp.1 Exp.2 Exp.3 Exp.4 Exp.5 NaCl 19.34 31.53 39.74 32.98 36.06 CaSO 4 anh 24.65 20.91 40.86 27.45 66.60 CaSO 4 * 2H 2 O 29.68 37.75 28.07 29.91 38.86 Ta l c 29.61 38.86 20.06 26.13 25.9 Regolith 66.5 57.5 46.66 50.88 50.80 Page of 5 6 105 DOI: 10.5821/conference-9788419184405.019 4 th Symposium on Space Educational Activities Barcelona, April 2022 2.5. Regolith interaction with textile Motivation for this experiment is checking the border conditions (high and low pressure) and see how well cleanroom textiles can protect against fine Regolith particles. 2.5.1. Regolith penetration through textile by applying only gravitational force Cleanroom textiles used in this experiment were by Dastex: ION-NOST A T VI.2 without Carbon, and PFG DAST A T I1800. Using elastic bands, the textiles were tautly fixed on the beakers. A certain amount of Regolith was placed on the surface of textiles using a sieve. Then the beakers were sealed for 7 days in a ch a mb e r t o e x cl u de ext e rn a l d i st u rb a nc e s suc h as stream ing air . Afte r 7 d ays , th e chamber was unsealed and the beakers were taken out of it. The regolith on the top of textile s u r f a c e w a s c a r e f u l l y r e m o v e d , a v o i d i n g particle shoehorning. After that, the textiles were taken for an analysis. Observed range of lengths of particles that penetrated the textiles: ION -N OS T A T VI .2 with out Carb on : 6 ,09 - 51,72 µm; PFG DAST A T I1800: 1 1,06 - 49,09 µm. Experimental results are presented in T able 4. T able 4 Experimental Data for Regolith penetration through textile by applying only gravitational force 2.5.2. Regolith penetration thorough textile by applying additional pressure T extile has been placed in a mortar , covering all mortar ! s surface. Regolith was placed on the surface of the textile, and then using a pestle it was forcefully pressed into the textile. W e have pressed 800 mg of Regolith against 26,5 cm 2 of both materials. The penetration rate, visually detected is in-between 5-10%. For calculation we have considered roughly 53 mg. The surface density of penetrated Regolith through textile (the control parameter) is then 53mg/26,5cm 2 , resulting 2mg/cm 2 , or 0,02 kg/ m 2 . 3. Conclusions The DEAR project has been successful in a c h i e v i n g i t s o b j e c t i v e s . S i m u l a t i o n s o f electrode structure suggests that on surface areas where alternating poles are entangled electrophoretic forces are pointing outward i.e., regolith will be removed outside of the covered area. Next steps will be the manufacture of p r o t o t y p e s t o e v a l u a t e t h e r e s u l t s o f s i m u l a t i o n , i n v e s t i g a t i o n o f e f f e c t s f r o m magnetic fields and adding the interaction between particles in simulations. Cleaning with CO 2 is also of particular interest because it can be used on a variety of human space flight hardware. Further investigations will be related to cleaning with CO 2 of robotic arm for wear issues and dust penetration. Robotic arm is an a s s e t f o r d o i n g e x p e r i m e n t s i n r e g o l i t h e n v i r o n m e n t s e . g . , t e s t i n g p o t e n t i a l degradation of space suits exposed to regolith an d te s t i n g me c h a ni c a l sy s t e m s i n du s t y environments. Regolith removal using mechanical shock is one of the simplest and effe ct iv e me th od s , bu t f ur th er res ea rc h i s required. Acknowledgements This project was supported by the European Space Agency . Following are the experts and contributors, as w e l l as o u r r e f e r e n c e f o r t h e p r e s e n t e d activities within the article: Andreas Pflug, P h i l i p p S c h u l z ( I S T F r a u n h o f e r ) , G e r n o t Groemer , Seda Özdemir-Fritz (OeWF), David McKeown (UCD), Ole Gusland (Gusland Consulting), Axel Mueller (OHB) and Christian Schwartz (ESA), to whom we thank for their wisdom, passion and patience shown to us. References [1] G.E. Groemer , M. Storrie-Lombardi, B. Sattler , O. Hauser , K. Bickert, E. Hauth, S. Hauth, U. Luger , D. Schild-Hammer , D. Foeger , J. Klauck: " Reducing biological contamination by a space suited astronaut: Laboratory and field test results from Aouda.X”, Acta Astronautica (2010), doi:10.1016/j.actaastro.2010.08.018 [2] A. Soucek, L. Ostkamp, R. Paternesi: " Suited versus Unsuited Analog Astronaut Performance Using the Aouda.X Space Suit Simulator: The DEL T A Experiment of MARS2013”, Astrobiology , vol. 15, issue 4, pp. 283-290, April 2015. DOI: 10.1089/ ast.2013.1067 T extile Mass of Regolith before experiment (mg) Mass of remained Regolith (mg) Mass of Regolith penetrating the textile (mg) ION – NOST A T without Carbon 307,6 286,1 21,5 PFG DAST A T I1800 299,8 270,5 29,3 Page of 6 6 106 DOI: 10.5821/conference-9788419184405.019 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 1 of 6 M o n i t o r i n g n a t u r a l p h e n o m e n a f r o m t h e c l a s s r o o m wi t h E d u s a t . P r o p o s a l f o r a t e a c h i n g g u i d e ( a n d s u p p o r t m a t e r i a l ) Rosa Olivel la 1 , Carla G ar cia 2 , Laura Olivas 1 , P ep Si tjar 1 __________________________________________________________________________ A bstr act Satelli te images and rem ote sensing allow us t o identify the effects of natural and hu man-made changes that occur on Earth: fires , f lood s, urban dev elopment, deforesta t ion , etc. Than k s t o the Copernicus p r ogram me , satel lite ima g es of the entire w orld are now availab le, with a near- daily frequency tha t all ow the identification and m oni t oring of all these natur al phenomena and human activ ities that produce notable changes to the Earth’s sur f ace. All t hese phenomena are forming part of the conce rn s of many young people who see the future of their planet in danger. The Edusa t platfo rm expl ores these phenomena from space and provides a didactic guide to understandin g the eff ects o f global environmen tal change, right i n the classroom. In this way , we bring remote sensing cl oser t o a public that un til now was rarely involv ed in this discipline. W e do it fr om a didacti c and pra ctical point of view , connected w ith real data from Sentinel satell ites and thanks to E O Brow ser appli cation. Key w ords Climate chan g e, Coperni cus, remote sensin g , satell ite images, teachin g material __________________________________________________________________________ 1 Geographic Inform ation System s and Rem ote Sensing Service (SIGTE) - University of Girona, Spain, rosa.olivella@ud g.edu 2 Facult y of Science – Un ivers it y of Girona, Spain. 107 DOI: 10.5821/conference-9788419184405.020 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 2 of 6 1. Introduction - Remo te sensing as an educational resou rce The social, econom ic and terr itorial d yna m ics that humanit y has adopted since the First Industrial Re volutio n h ave led to t he indiscrim inate consum ption of natural resources. The exploitation of these resources has put the well- being of the inh abitants of planet Earth, as well as th e ph ysical s ystem s that supp ort it, at s evere r isk . This process h as been desc ribed as “ Global Env ironmenta l Change” and results i n f our well -k nown phenom ena: pollutio n, b iodiversit y loss, change in land use an d land cover, and clim ate chan ge [1] [2]. The scientific strength of the negative consequences of clim ate c hange, pollution or biodiversit y loss f urther intensif ies critical reflection am ong citizens. This sense of protes t and s truggle is es peciall y in tense among y oung people, who are f ighting against the pas sivit y of politicians f or po licies to m itigate clim ate change. As s uch, these young people nee d t o have th e necessar y com petences in order t o evaluate and dissem inate the conseque nces of global e nvironm ental chan ge in a c ritica l and objective m anner. The availab ility of sate llite im ager y f rom around the world o n a dail y bas is (depending o n weather conditions) m ak es i t eas y to identif y and m onitor all of these n atural phenom ena and anthropic proces ses th at in volve not able changes to the land surface [3]. T hese images taken f rom space m ake it possible t o stud y t he evolution of natural an d anthropic episodes such as wildf ires, floods, melting g laciers , deforestation or urbani zation [4]. Copernicus is the Earth obs ervatio n program coordinated and m anaged by the Euro pean Comm ission and the Eur opean Environm ent Agenc y , wit h the aim of providing acc urate a nd up - to -date i nform ation on six areas: c limate change, s ecurit y, emergenc y, atm osphere, m arine environment, and land surf ace [5]. All of this inform ation is especiall y designed to provide a globa l view of the Earth ’s hea lth, wit h the aim of helping governm ents to f ocus on environmental p olicies and to eff ectivel y m onitor their im plementation. Industri es, organizations and re searc hers are also encouraged to m ake use of this data in conjunction with the ir ow n da ta in order to develop new functi onalities and app lications . Copernicus of fers a c om plete s et of open data, including t he large v olum e of im ages captured from Sentinel sate llites. T his data is a vailable through various websites, applications and services, a nd it is desi gned f or diff erent user profiles, f rom highly s pecialized to less experienced ones. The Edusat project [6 ] pres ented in th is paper aims to s et out, in an educat ional and interactive way, the fundamentals of rem ote sensing in order to make the process of col lecting a nd processing sat ellite images unders tandable . Theref ore, the m ain objecti ve of this reference m aterial is to present rem ote s ensing to a n on - sp ecialized a udience and to off er a user- friendl y tool for the a nal y sis of land surface changes as well as a tool f or the disse m ination of results . 2. Th e Edusat platform Edusat is a web platform that contains educational r esources f or explor ing satellite images that are open to th e ent ire educati onal comm unity. The web s ite was launched in Ma y 2 021 and is a multilingual (C atalan, Spanish and En glish) platform . Edu sat offer resources in a dynam ic way (images, videos, tim e lapses, m aps, gifs, etc.) in ord er to clear ly explai n glo bal environmental cha nge. The resources off ered are: - basic pri nciples of rem ote sensing, - cas e s tudies (explaining various natural and anthropo logical ph enom ena), - exerc ises to work on with the EO Browser teachi ng guide. Using Edusat, we pro pose a teaching guide that aims to bring rem ote sensin g to a non- specialized au dience and t o provide teac hers, students an d researc hers with support m ater ial. This paper s ets out a t eac hing guide for a classroom work shop. The overall aim of Edusat is specif ied in these three specif ic objectives : - To introduce stude nts t o the fie ld of r em ote sensing and to sho w them how t o ide ntify re al natural phenom ena. - To introduce stu dents to the C opernicus programm e, givin g them acces s to f reel y available satel lite images. - T o enable studen ts to i dentif y the causes and consequences of natural p henomena such as floods, drought, def orestati on, etc. Th e purpose of m aking t he materials openly available is t o empo wer users to learn about a resource, regardless of whether or not they have c om pleted t he c ours es we off er. T he dissem ination of the materials enable s an yone 108 DOI: 10.5821/conference-9788419184405.020 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 3 of 6 to bec om e f amiliar w it h th e applications an d the usefulness of satellite im ager y. At the mom ent of writing this paper there are nine case s tudies developed that allow us t o dem onstrate the usefulness of satellite images to observe and anal y ze the current phenom ena of global en vironm ental change. T he case studies ar e accom panied by videos whic h explain step by s tep how to obt ain the results we s how f or each phenomenon studied so that the user c an get the same res ults using th e videos as a qu ick -start guide. 3. Th e learning material The tea ching guide i s th e pr oposa l that w e off er educators to use Edusat in order to work with rem ote sensing and case studies in t he classroom . It is structured as a single s ession -or set of sessions, depend ing on te aching context - wi th different parts or b lock s (Figure 1). 3.1. Block 1. Con text and assumptions Estimated dur ation: 2 ho urs 3.1.1. Context The first block c omprises of a t heor y sessi on in which th e teacher explains the principles of rem ote sensing (satellites, sensors , electrom agnetic radiation an d ban d combinations), sho wing students how th is technolog y c an he lp to detect nat ural disasters or human activit y resu lting f rom the climate crisis. T he goal of this block is to provide the students with co ntext on the issu e of gl obal environmental change and t o exp lain the principles of rem ote s ensing in a simple, enjoyable wa y. 3.1.2. EO Bro wser [7] This block also contains a s ect ion in which the teacher s hows t he s tudents how to use the EO Browser ap plication to s earch for s atellite images and m ake band c om binations. EO Brows er is an a pplication d eveloped b y the Sentinel Hub com pany [ 8] which m ak es it possible to view hi gh -reso lution images from Sentinel, Landsat an d ot her satellites on a single website. Furtherm ore, the EO Br owser enables users to create com parisons or time lapses of satellite images so that the c hanges that h ave occurred in the territor y ca n be easily identif ied by comparing several images tak en on diff erent dates. For now, th is application is an open-acces s tool that off ers basic functions such as displa ying the natur al-colour images of satellites; as well as advance d par am eters of ban d com binations or th e app lication of m ulti ple indices through inter-band algorit hm s. Figure 1. Teaching gu ide infographic 3.1.3. Case s tudy The students exp lore real exam ples of phenom ena f rom around the wor ld t hat ca n be studied using satellite i m ages and wel l- docum ented case studies availab le in Edusat, related to phenomena s uch as f ires, f loods, 109 DOI: 10.5821/conference-9788419184405.020 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 4 of 5 Figure 4. Absorb ent Pad s Test 2.5. Therma l R EQ : The exp eriment s hall have nom inal performance a t temperatur es of u p to 45 °C. REQ: The exper iment shal l ma intain functionality with nominal performance after being exposed to a temper ature of almos t -30°C before the fl ight. Extreme tem peratures mus t be cons idered before the operat ion of t he experiment . T he launch wi ll take p lace fr o m the ESRANGE launch site ins ide the Ar ctic Circle . s o, the experiment co uld be ex posed for a long per iod of time to very low temperatures before the launch. Also, the heat coming gen erated during the flight can drastica lly rise the temp erature inside o ur exp eriment module before th e milligravity perio d. The proc edure cons isted in artificially ex posing the experi ment to low ( using a house hold freezer) and high (using a lab oven) temperatures and running the fu ll pr inting sequence immediate ly after (see Figure 5). T his test is quite conservative as in reality, th ermal insulation is use d ins ide the rocket modu le and the org anizers can he at t he rock et to a desired temperature bef ore the f light. The succ ess c riteria was repres ented by the success ful completion of the printing procedur e after the cold/h eat exposur e. Figure 5 . High (left) and L ow( right) temp. tests 2.6. Vibrati on REQ: T he experiment shall withstand the vibration loads during the launch of REXU S rocket. Figure 6 . Vib ration Test Set - Up The vibrati on test was the most conventional test performed by o ur team c ompared with all the others . The procedure was entire ly specified by the REXUS User Manual [4] and by t he REXUS/BEXU S orga niser s. The exper iment was mou nted on a shaker a nd differe nt vibra tion input pro files were used while observin g an d recording dat a from the accelerometers p laced on different sp ots on the experim ent’s body . One of the ch allenges of performing the test was the d esign a nd ma nufacturing of the interface bo ard to the s haker that was need ed to match the shaker m echanical interfaces with our experiment. The success criteria was to have a functiona l experiment after exposed t o vibratio ns. 2.7. Vacuum REQ: The experim ent s hall have n ominal performance in v acuum c onditions (pres sure below 0.5 mbar) . Most of t he electronics used are off - the -sh elf components that w ill be ex posed t o vacu um for a short t ime durin g operation in mi lligravity. For this reason, a ll the electronics parts wer e teste d while in operation insid e a vacuum chamb er at a pressure of less than 0.5 mbar. The proc edure consiste d in runn ing t he electronics with the printing software inside the vacuum chamber while measur ing and recording tem perature dat a via the sensors placed on the most critical p arts of th e assembly (the s tepper- motor and the most p ower consuming chips of the PCB). To command the electronics while inside the cham ber, we implemented a Bluetooth communication that allowed us to c ontrol the pr ocess. 116 DOI: 10.5821/conference-9788419184405.021 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 5 of 5 The success criteria consisted of confirmin g full functionality of th e electron ics while inside the vacuum chamber and t o prove that t he hotspots’ temperatures of the assembly were i n line with the re quirements. Figure 7 . El ectronics Vacuu m Test 3. Results All the test procedures presented in S ection 2 were suc cessful ly carr ied out by the team in the given t imefram e. The Therma l Test was performed w ith some delay as the initial plan was to acc ess a thermal chamber but given t he high n umber o f CO VID i nfections at th at t ime, we continued w ith the freez er/oven pr ocedure. All th e suc cess criteria were achieved, an d extensive test rep orts were delivered to the campaign pane l. The test activities ende d with a succes sful Experi ment Acceptance Review and with the d elivery of th e experim ent to the REXUS/BEXU S organiser s for the launch campaign pe nding to take place in 202 3. 4. Conclusions The test campaign execut ed by the ECRIDA team p articipating i n th e REXUS/ BEXUS framework is presented. O ur method of designing th e camp aign, the constra ints we faced, and a high-leve l des cription of every test performed are described with focus on t he more general aspects and w ithout digging i nto the specifics of our experi ment . The purpose of t he authors is to make a ll the informa tion val uable to any stud ent proj ect that will be hosted by a launch v ehicle a nd that must under go test procedures. Given the c ircumstance s of the CO VID pandemic, our team faced v arious ch allenges while p erforming the test p lan but eluded them with c onfide nce resulting in a succ essful test campaign. The experiment was delivered to the REXUS/BEXU S org anizers and no w fi nal preparations for the launch are perf ormed . Acknowledgem ents The team behind ECRIDA would like to acknowledge the inva luable h elp duri ng the testing campaign of prof. Bogdan Vasile and prof. Bogdan Ionescu fro m CAM PUS Researc h Centre, U niversity P olitehnica of Bucharest, and Claudiu Cherci u from t he Roman ian Institute of Space Sciences. T he team grati tude also goe s to our advisors from t he R EXUS/B EXUS framework : Koe n DeBeu le (ESA), Armelle Frenea-Schmi dt ( SSC), Dieter Bischoff (ZARM), and to al l the people involved in organising and running this amazing campaig n. The au t hors would also like to acknowledge th e institutional and private sponsors of ECRIDA , namely: U niversity Politehnica of Bucharest, Thales, GM V, RISE, T ech Lounge Ass ociation, 2Space, Fau lhaber, Top Metrology, SNS A, DLR and ESA. References [1 ] Sacco, E., & Moon, S. K . (2 019). Additive manufacturing for sp ace : status and promises . The Internat ional Journ al of Advanced Manuf acturi ng T echnology [2 ] Haoyuan Quan, Tin g Zha n g, Ha ng Xu, Shen Luo, J un Nie, X iaoqun Zhu , Photo- curing 3D pri nting techn ique and its challenges . Bioactive Materials, Volum e 5, Issue 1, 20 20 [3] Projec t ECRIDA Website : www. ecr ida- rexus.github.io , last v isited: 21 st Marc h 2022. [4] REX US User Ma nual: www. rexusbexus.n et/rexus/r exus -us er- manual , last v isited: 21 st M arch 202 2. 117 DOI: 10.5821/conference-9788419184405.021 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 1 of 6 D e v e l o p i n g a 3 U C u b e S a t E n g i n e e r i n g M o d e l - F l a t S a t & C h a s s i s D e s i g n Willi am Crofts 1 , M att ias L anger 2 , Alex Bolland 2 , Ta hrim Uddin 2 , C hiara Biquet 2 , Edua rd Hopkins 2 , Jai Bassi 2 , M yles Ing 2 , Julia Hunter - And erson 2 ____________ _________ ________ ___________ ____ ____________ _________ ________ _ Abstract WUSAT-3 is a 3U Cub eSat being designe d to c arry an experimental RF sig nal d irec tion fin ding pa yload in Low Earth Orbit (LEO). Success ful outc ome of this experiment could l ead to significant benefits for the f ield of wildlife mon itoring from Space. Commerc ial adoption of this proces s would enable the development and use of muc h smaller, lighter RF t racking tags , which in tur n would co nsiderably increase the potential r ange of spec ies that could be tr acked by S atellites. The effect of the Covid- 19 pandem ic lockdowns has limited phys ical progress over the past 18 months, but the team continues to g ain e normous experience and mot ivation fr om purs uing this exc it ing proj ect with a very re al-w orld mission. A recent return to near - normal w orking p atterns has ena bled t he team to fully engage w ith t he prac tical ities of pro gressing the previous ly prod uced WU SAT -3 C onfiguratio n Model, towards a testable Engineering M odel. This paper outlines t he dev elopment of both t he initial chass is prototype ( includin g mechan isms) a nd a subsystem F latSat as a firs t stage towards building th e complete Engineer ing Mod el. The c hassis prototype was required t o meet a ll the r e quirement s of t he FY S D esign Specification [1], the NanoRacks Cub eSat ICD [2], the Cub eSat Desi gn Specificat ion [3] and thos e features iden tified by the outcomes of the WU SAT -3 Configurati on Model. The FlatS at w as required to include a ll subs ystems capable of be ing constructe d a nd t ested wi thout the availability of c ertain proprietary items that will be purchased later. The function and interface of t hese items, where it was necessary for the purpose of tes ting th e assembled s ubsystem units that were available, was met by the design and inclusio n of temporary s ubstitute arrange ments that provided similar performa nce. Systems Engineer ing methodo logies were emp loyed throug hout as a means of e nsuring that th e design features of both ch assis an d FlatSat me t all necess ary requireme nts. Keywords CubeSat , Engineering- Model , F latSat , S pace, System s, ____________ _________ ________ ___________ ____ ____________ _________ ________ _ 1 William Crofts, Universi ty of Warw ick , United K ingdom , W. E.Crofts@warw ick.ac .uk , 2 University of W arwick , Un ited Kin gdom 118 DOI: 10.5821/conference-9788419184405.022 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 2 of 6 Acronyms/Abbr eviations ADC Analogue- to -D igital Co nver ter DDD Direct Dis placeme nt Damage DoD Depth of D ischarge EEPROM Electr ically Er asable Programmable Read-Only Me mory EM Electroma gnetic EPS Electr ical Power Sys tem FlatSat Flat Sate llite, internal subsystems of the satellite c onstructed an d connected outs ide of the ch assis FYS Fly Your Satellite LDO Low -Drop out LEO Low Earth Or bit OBDH On -Board Data Handl ing RF Radio Frequency SEE Single Eve nt Effect SEU Single Event Ups et TID Total Ionizin g Dose TMR Tr iple Modular Re dundanc y WUSAT Warwick Un iversity Satellite XCAM The CubeSat C amera & Co mpany Figure 1. WU SAT-3 Cub eSat Di agram 1. Introduction In prev ious years, work carried out has been highly c oncept ual i n nature , ow ing in no small part to the impact of t he Covid- 19 pandemic. Building upon t he work of prev ious t eams, the focus this ye ar was tra nslating con c eptual designs into re ality – manuf acturing, assembling, and testing as ma ny CubeSat subsystems as possible in preparation for the project’s am b ition of admiss ion to the Europe an Space Agency’s S atellite P rogram [1 ]. 2. Discussions Detailed be low is a s ummary of each subsystem develo ped this year by the WUSAT - 3 te am , outl ining the key design features, their function , the ir testing an d v erification as w ell as relevant major c onsider ations for each. 2.1 Chass is The primary f unction of the chassis is to support the pay load’s ability to fulfill the satel lite’s mission. It provi des a stable ba s e to secur e internal c ompo nents during launch fro m Earth , as well as to withstand the vibrations and large forces experi enced. The ch assis c onsists of tw o side pane ls whi c h i ncorporate four external rails, nadir and back pa nels, top and botto m plates alongs ide an additional intern al structura l support . The panels act a s anchors to attac h multiple patch antennas in addition to the s olar panels requ ired to power the s ystem. W here required, cut outs were implemen ted to facilitate connections betw een exter nal compon ents and internal sys tems, with al l de signs c onforming to the dynam ic envelope spec ification [1] . 2.2 Chassis Testi ng Static stress testing was conducte d using finite element s oftware. Thro ug h Abaqus r elevant parameters s uch as Von Mises str esses highlight areas which may be prone to yielding failures from lo ading and vibrati on during launch. This information has be en used to inform design on key loadbeari ng components wh ere rein forcement or r edesign has been required . Additional simulati on outputs investigated c omponent deflect ion, wh ich is presented as the displacement magnitude in Abaqus. The first simu lation for stres ses in th e X ax is shows v alues lie we ll wit hin t olerate d levels peaking at only 42.90 MPa. The maximu m deflections of 0 .04 mm are also w ell within reasonable s afety m argins. Similar results ar e seen across the Y ax is w ith peak s tress at 68. 86 Nadir facing side Deploya ble patch antennas Fixed pa t ch antennas XCAM Figure 2. Re sults of simu lation in Y axis showing th e Von Misses stress in MPa (left) and def lection in m m (right) 119 DOI: 10.5821/conference-9788419184405.022 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 3 of 6 MPa c ausing a 0.1 8 mm deflection, and over the Z axis a pe ak 73. 18 MP a resulted again in a small 0.18mm deforma tion. With the use of aluminium 7075 as the material for the chas sis construction t hese forc es are well b elow the 31 0 MPa yield limit. Dynamic vibrational testing was al s o performed to g ain insight on the natu ral fre quency of the satellite chass is. Th is was carried o ut in s imilar fashion by s imulat ion - with res ults yiel ding a first natura l freq uency 547.77Hz, which is wel l outside t he requ ired m inimum tolerated 130Hz [1] . Th is testing however, indicated that large deformations of the struct ure up t o 8.68m m could occur, which could potentially dama ge internal co mponents , whi lst also pot entially exceeding the a llowable dy namic enve lope [ 1]. 2.3 Internals The i nternal compone nts are separated into ‘shelves’, each containing a m otherboard wi th the PC/10 4 form factor. Sta ndoffs sit uated i n th e corners of each s helf, allow them t o b e arr anged into a stack con figuration ac ross the axial length of the C ubeSat , a nd maintain c ontrolle d separation between each internal com ponent . This shelf stack fits wit hin the chassis and is attached via the sta ndoffs at two mountin g points, loc ated a t t he top and b ottom p lates respectively. Figure 3. Conf iguration of Component Shelves 2.4 Patch Antenna Fr ame a nd Hing e There are f our payload pat ch ant ennas on t he CubeSat ( Abracon A RRT N5- 915.000 MHz ), each receiving data fro m the freq uency of the RFID tags. T wo are fixe d and located on th e nadir (Y+) panel of the satellite, a nd two are deployable from the side pane ls. The latt er are constrained w ith a hinge to the X+ and X - panels respect ively, where a de ploymen t mechanism a llows them to rotate 9 0° about the Y ax is to face th e Earth. Deployable ant enna mechanisms were neces sary , as there is insufficient s pace on the n adir panel to host al l four of t he earth facin g an tennas re quired by the payload – g iven the pos ition of the cam era aperture. Give n th e thickne ss of 6.9 mm of the antenna module, thes e could not be mounted flush on to the s ide panels o f the chassis since it will exceed the maximum 6.5 m m of a llowable dynamic enve lope protrud ing fr om th e sid e. Therefore, a recess in the aluminum chassis was implemented to house the patch antenna in its deployed conf iguration. 2.5 Deployment M echanisms The r eliability of the deplo yment mechanisms for the patch and TM/TC an tennas was a criti cal factor for gu arantee ing the success of the WUSAT-3 miss ion. For this reason, the deployment mecha nisms underwent rigor ous design, testing and valida tion to ensure the designated mechan isms were s ufficient. Both deployment mecha nisms utilize a nichro me melt w ire d evice to release the appropriate spring-loaded deployment mechanism for the respective a ntenna system. In order t o increase the effective ness of the burn wire break point, a spring me c hanis m pul ls the melt wire in the direction o f cutting across the respect ive b urn wire. Collective ly this mechanism is k nown as a “thermal knife”. Figure 4 . WU SAT Deplo yment Mech anism s To reduce th e likelihood o f deployment failure – which would result in mission failure, redundant pairs of t hermal knives were em ployed in the deployment mechanisms for each an tenna . During testing, it was discovered that a sufficiently high curr ent of 2. 6 A would b e required to ens ure a succes sful c ut within the acceptable time fram e ( < 10 s ec onds). For this reason, it wo uld be necessary to activate only a single therma l kn ife at a ny gi v en mom ent, to 120 DOI: 10.5821/conference-9788419184405.022 4 th Symposium on Space Educational Activities Barcelona, April 2022 Page 4 of 6 remain withi n the limi ted p ower budget ava ilable from the s atellite’s battery. Thus, a sensor would be employed t o detect unsucc essful antenna deployment and en able power to be re- routed to the redundant thermal knife. In addition, t his d esign cho ice elim inates the possibility of burn wires be coming a sourc e o f space debris. 2.6 Thermal Radiati on Conside rations Despite the abu ndance of literature about thermal radiation effects and shi elding pertaining to C ubeSats, th ere is a significant dearth of investigations into the effect of t hermal radiation in space on t he temperat ures of internal el ectronic co mponents . Th is lack of analysis s eems str ange – giv en that the i nter nal electronics are the co mponents for which a suitable te mperature eq uilibrium must be maintained. F or this reason, building on d ata obtained throu gh prev ious thermal an alyses, a n investigation into the effects of thermal radiation – an d spec ifically – how they affect t he temperatures of inter nal electronics, was undertaken. T he data y ielded that, wit hout insulation, the curr ent design of t he WU SAT - 3 CubeSat would not be capable of suff iciently insulating its interna l e lectr onics, a nd that the minimum and maxim um temperatures of at least one or several compon ents would be exceeded i n wors t case, eclipse, or m aximum solar flux sc enarios. Figure 5. Internal Operati on Temp erature This resulted i n the i mp lementati on of aluminumized mylar multi-l ayer insulation w ithin the interior of the chassis pane ls betwe en the outer fac es an d th e internal c omponents. With the add ition of t his new insulat ion, res ults determined that th e Cube Sat would be c apable of e nsuring sufficient ther mal stab ility for the duration of its deployment “surv ival” period, as well as the e ntire mission. 2.7 Electrical Power Sy stem (EPS) Figure 6 ill ustrates the block diagram of the EPS, showin g the b asic layout for the power network. Power is generated by photovoltaic cells a nd su bsequent ly tra nsmitted t o th e EPS control, which incl udes c omponents s uch as buck converters and additi onal subsystems to protect against un der and over voltages. After this, the E PS c ontrol can proceed to distri bute th is power to t he battery to charge it as well as to sensin g subs ystems wi thin th e Cu beSat. The On Board D ata Handling ( O BDH) contr ols t he EPS sy stem and batt ery - distributi ng store d charge when n eeded a nd with in the c orrect operating conditions . The battery o utputs a range of voltages depending on the a mount of remaining stored char ge. I n id eal c onditions, i t outputs 8.26 V DC, how ever this mus t s till be reduc ed to a usable vo ltage for the range o f components on t he sat ellite. This is achieve d with two buck converter s ; one to deliver regulated power to various subsys tems and the other the delivered pow er to the O BDH microcontroller. These buck c onverters are a part of the pow er distribution in F igure 6. They were success fully designed , man ufactured, and tested and are able to provide sufficient power to the satellite during opera tion . Figure 6. E PS Block Diag ram 2.8 EPS Testing The constructed buck converters, s een in Figure 7 Error! R eference source no t foun d. , were test ed for the ir outpu t voltages a nd the ir ripples to determ ine if the y were suitable a nd could thus be accepted as feasible for further development. The LM226 79 buck converter was found to successfully supply 5 V a nd 3.3 V power r ails for various s ubsy stem s, although outputs were meas ured at 5.2 V and 3.6 V respectively. The LM103 6 buck converter delivers exactly 3.3 V to the microcontrol ler (PIC16), as desired. The ripple of all t he po wer rails was found t o be n egligible d ue to the Lo w Dropout (LDO) regulato rs, names given respectively for each buck convert er. 121 DOI: 10.5821/conference-9788419184405.022 [Document text truncated for crawler view.]