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Peer-review under responsibility of Assembly Technology and Factory Management/Technische Universität Berlin.

doi: 10.1016/j.procir.2014.07.032

Procedia CIRP 26 ( 2015 ) 58 – 63

ScienceDirect

12th Global Conference on Sustainable Manufacturing

Graphical Visualization of Sustainable Manufacturing Aspects for

Knowledge Transfer to Public Audience

Wei Min Wanga*, Lars Woltera, Kai Lindowa,b, Rainer Starka,b

aDepartment for Machine Tools and Factory Management, Technische Universität Berlin, Pascalstr. 8-9, 10587 Berlin, Germany

bDepartment forVirtual Product Creation, Fraunhofer-Institute for Production Systems and Design Technology, Pascalstr. 8-9, 10587 Berlin, Germany

* Corresponding author. Tel.: +49-30-39006-272; fax: +49-30-393-02-46. E-mail address: w.wang@tu-berlin.de

Abstract

Sustainability is characterized by complex interplay between economic, environmental and social aspects and a temporal di-

mension. The public perception is often mistakenly limited to single aspects due to deliberated influence by marketing or misuse.

Reliable scientific articles usually address expert audience only. To create a broad public understanding knowledge has to be

available and comprehensible. In the World Wide Web various concepts are applied to represent knowledge each utilizing differ-

ent sets of media without interactive elements. To get an overall picture of sustainability an understanding of complex relation-

ships is necessary. Non-interactive text based approaches lack the necessary capabilities to present this picture. This paper pre-

sents a graphical approach involving a simplified product configurator based on an ontology developed in the CRC1026. It em-

bodies gamification elements to draw people’s attention and uses ontological trees to illustrate relationships.

Peer-review under responsibility of Assembly Technology and Factory Management/Technische Universität Berlin.

Keywords: Sustainability; Knowledge transfer to public audience; Ontology; Gamification

1. Introduction

The understanding of “Sustainability” has come a long way

since it was first conceptualized by Hans Carl von Carlowitz

in 1713[1]. The report of the “Brundtland” Commission in

1987 laid the foundations of the modern understanding and

took it into public discourse [2]. It defined sustainable devel-

opment as “development that meets the needs of the present

without compromising the ability of future generations to meet

their own needs” [3]. This definition has been complemented

and modified ever since by various organizations on interna-

tional (e.g. UN Conferences on Environment and Develop-

ment in Rio de Janeiro1992 and 2012, Johannesburg 2002)

and national level (e.g. the German Enquete Commission on

Protection of Humanity and the Environment 1995) in order to

clarify its meaning and to adjust it to present conditions [4, 5].

Recent models usually describe sustainable development in

the context of the three sectors economy, environment and

society. Although the philosophies behind the models may

vary they all embodies the fact that those sectors or pillars

cannot be treated separately but with regard to their interde-

pendencies. There is also an agreement that sustainability not

only means shifting our lifestyle and economy according to

societal and environmental limitations but also to balance the

inequities between industrialized and developing countries.

[6, 2]

One way of bridging that gap is to reshape the nature of

global value creation to meet the requirements for future sus-

tainable development. This is also the vision and the mission

of the Collaborative Research Center 1026 – Sustainable

Manufacturing (CRC 1026, www.sustainable-

manufacturing.net). This project brings researchers from dif-

ferent disciplines together to work collaboratively towards the

goal of sustainable manufacturing. One important step to

achieve that goal is to communicate the benefits of sustainable

or sustainable manufactured products (hereafter called sus-

tainable products) into the general public. From a scientific

point of view this step proofs to be quite challenging as the

(http://creativecommons.org/licenses/by-nc-nd/3.0/).

Peer-review under responsibility of Assembly Technology and Factory Management/Technische Universität Berlin.

Wei Min Wang et al. / Procedia CIRP 26 ( 2015 ) 58 – 63

concept of “Sustainability” as a complex structure that is char-

acterized by the interplay of economic, environmental and

social aspects and with regard to a temporal dimension has to

be simplified without biasing its holistic meaning. Although

there is plenty of information about sustainability in the World

Wide Web (WWW) there is still a lack of proper concepts to

present such information in a comprehensible and pleasant

way.

To face the challenge of improving the public understand-

ing of benefits of sustainable products this paper proposes an

approach that utilizes gamification aspects to encourage peo-

ple to deeply explore the concept of sustainable manufactur-

ing. The concept is developed within the CRC1026 and uses

research results generated during the course of the project. The

starting point is a simplified interactive configurator for a

Pedal Electric Cycle (Pedelec) where the user takes the role of

a design engineer. The user can influence the sustainability

characteristics of the pedelec by configuring it with features

from a predefined collection. Effects of the user’s choices will

be calculated and visualized in real time. To provide an easily

comprehensible presentation of the underlying interdependen-

cies ontological trees are applied to visualize relationships

between relevant concepts.

2. What hinders the general public to clearly understand

the benefits of sustainable products?

Although the consciousness for responsible or ethical con-

sumption has increased in the recent years [7] the benefit of

sustainable products is still often unclear to the general public.

Usually, consumers associate such products with higher prices

but with no obvious practical advantages. The idea of “Sus-

tainability” is becoming a catch phrase for the general public

that is somehow used and interpreted unequally [8, 9]. One

reason is that a comprehensible definition is still missing de-

spite or perhaps because of ongoing efforts to find a universal

definition by politicians, non-governmental organizations

(NGOs) and companies. This leads to a confusingly high

number of possible interpretations allowing all kinds of actors

to claim themselves to be sustainable. Furthermore, the lack of

reliable and comprehensible sources of information permits

and facilitates the misuse of “Sustainability”. [2, 10]

For decision making in their daily life consumers often

have to rely on information provided by the companies or on

various quality seals like “Fairtrade” (www.fairtrade-

deutschland.de) or the “EU Ecolabel” (www.eu-ecolabel.de).

Unfortunately, both sources proof to be of only limited relia-

bility. Company presentations may lack the necessary trust-

worthiness as sustainability phrases may be embodied unjusti-

fiably to improve the company’s image (Greenwash). From a

business point of view such action can be quite profitable as a

“green” image can have significantly positive influence on

market shares and position while regulations regarding penal-

ties for such fraudulent claims are “lax and uncertain”[11].

Regarding quality seals the problem lies in the countless varia-

tions of labels existing for numerous product categories. Some

of them are awarded by non-governmental and governmental

organizations (e.g. “Blauer Engel” by the German Federal

Ministry for the Environment, Nature Conservation and Nu-

clear Safety) and some are even introduced by single compa-

nies (e.g. “Pro Planet” by the REWE Group). A study con-

ducted by the German Öko-Institut e.V. in 2012 revealed over

50 different seals for seven product categories that are some-

how related to sustainability [12]. Consequently, we propose

that one hurdle for public audience to grasp the benefits of

sustainable products is determined by the four criteria availa-

bility, comprehensibility, reliability and proper presenta-

tion of relevant information. To assist consumers in making

informed decisions all four criteria have to be met, but in reali-

ty there is often the dilemma that some of these criteria con-

tradict each other. For example, available and comprehensible

information may be unreliable as they could be intentionally

provided by companies to improve their image. More reliable

information such as independent studies or scientific papers

usually address expert audience only and are thus not compre-

hensible to the general public and sometimes even of limited

availability (e.g. due to fee based access).

Another hindrance is related to the complex nature of mod-

ern product creation with its network structures and early

product lifecycle (PLC) considerations. A valid assessment of

products not only demands the sustainability dimensions to be

additionally considered in combination with the value creation

network behind it but also detailed PLC analysis [13]. Modern

products usually consist of a multitude of mechanical, electri-

cal and electronic subsystems and additional software compo-

nents each produced by a highly specialized company in glob-

ally distributed networks [14]. The PLC includes “the entire

planning and development of products including the corre-

sponding equipment, resources, assembly and production

processes, its manufacturing as well as its utilization, opera-

tion and recycling” [15]. Taking these two aspects into con-

sideration it becomes clear that for non-experts it is almost

impossible to grasp the complexity.

3. Application of ontological trees to visualize sustainable

manufacturing aspects for knowledge transfer

An often underestimated aspect of knowledge transfer is

the presentation form of information. In the WWW various

concepts (e.g. Wikis, Glossaries, Tutorials) are applied to

represent knowledge each utilizing different sets of media

(e.g. text, video, audio), but mostly without interactive ele-

ments. In terms of sustainable manufacturing such static rep-

resentations are insufficient as an understanding of complex

relationships is necessary. Instead, a representation form is

needed which is capable of reducing the complexity according

to the recipient’s requirements, the general public in our case.

In the CRC1026 nineteen sub projects with over 70 re-

searchers from different disciplines are working collaborative-

ly towards the goal of sustainable manufacturing. Each sub-

project contributes expertise on a very specific aspect of sus-

tainable manufacturing. In order to draw an overall picture of

the involved knowledge domains and their relationships and to

help the researchers to understand those relationships an on-

tology is developed [16].

60 Wei Min Wang et al. / Procedia CIRP 26 ( 2015 ) 58 – 63

Ontologies are formal representations of the shared under-

standing of certain domains of interest. Here, the world view

of the domain is conceived as a set of concepts and their rela-

tionships. [17] With proper tools (e.g. CmapTools,

http://cmap.ihmc.us) ontologies can be visualized as treelike

graphs (see Figure 1) where the concepts are represented as

nodes and the relationships are named edges between the

nodes. Other tools enable such ontological trees to be explored

sequentially and thus partly hide the complexity of huge net-

works from the viewer (e.g. RelFinder,

http://www.visualdataweb.org/relfinder.php). In case of the

CRC that kind of representation possibilities seemed particu-

larly suitable as they would allow the researchers to explore

the network of involved concepts in a controlled way. They

can either display the complete network at once or decide to

navigate from node to node. Similarly, ontological trees can

be used to introduce the public audience into sustainability

aspects without overwhelming them with the whole complexi-

ty of the concept.

4. Gamification

As described above the topic of sustainability is rather

complex and therefore takes time to supply an interested per-

son with the necessary knowledge. In the context of the gen-

eral public the interest in picking up information without be-

ing forced to (by work, school or similar) is decreasing if too

much time is necessary to supply the knowledge. Gamification

addresses this topic by the use of game design elements in

non-game contexts [18]. Gamifictaion provides elements that

keep the interest of a person to a specific topic by using design

elements like scores, achievements and storylines. Adding

gamification concepts to the product configurator seems logi-

cal to raise the time an interested person will learn about sus-

tainability. Different Gamification Design Elements where

chosen to motivate the user.

x Mechanics of the configurator which construct a system

of interacting parts that can be combined to achieve dif-

ferent results, therefore exploring the different sustaina-

bility impacts of the pedelec parts is necessary to under-

stand the game mechanics.

x Feedback visualization which shows the result of the

combination by delivering not only values in terms of

graphs but also by visualizing them using a 2D/3D repre-

sentation of a pedelec giving the ability to create their

own styled bike.

x Fun motivator – role play, by putting the user into the role

of a design engineer with the task to create a sustainable

pedelec.

x Fun motivator – research, by using the ontologies to visu-

alize the complex network behind the sustainability of the

pedelec which allows the user to explore those networks

discovering new relations.

Using the above gamification elements enriches the config-

urator in a way that users are kept interested to supply them

with more information about sustainability during the usage of

the configurator.

5. Concept of the Product Configuration Game (PCG)

The idea of the PCG is to raise awareness for sustainability

and to demonstrate the complexity behind it by using simpli-

fied examples. For the PCG the user will be put in the role of a

design engineer whose objective is to configure a contempo-

rary pedelec for the German market with the best possible

sustainability characteristics. In the PCG these characteristics

are represented by Sustainability Values which can be influ-

ence by the design decisions made by the user.

Due to simplification matters we consider only the Frame

and small number of Functional Features to be relevant for

the configuration of a pedelec. The Frame can be made of four

possible materials: Aluminium, Bamboo, Stainless Steel and

Titanium. Each frame type can be obtained from three Suppli-

ers located at different regions. Supplier A is located in West-

ern Europe (e.g. Netherland), Supplier B in Southern Europe

(e.g. Italy) and Supplier C in Asia (e.g. Malaysia). Relevant

Functional Features include Motor, Battery, Computers

Systems and Charging Options.

Figure 1: Excerpt of Sustainable Manufacturing aspects for the Pedelec example visualized as ontological tree (does not cover all sustainability aspects). The

Pedelec (orange) is the root. Yellow boxes represent the main concepts (classes). Green boxes represent sub sets of main concepts (sub classes). Grey boxes

represent concrete instances on the lowest level (individuals). Named arrows represent relations between the concepts.

Wei Min Wang et al. / Procedia CIRP 26 ( 2015 ) 58 – 63

Possible motors are a Standard Electric Motor or an Elec-

tric Motor with Regenerative Braking. The battery type can be

Battery Type A with low efficiency or Battery Type B with

high efficiency. Computer Systems can be a Smartphone Con-

nector or a Driver Assistance System. As Charging Option a

Solar Panel can be equipped. This set of predefined options

simulates existing supply chains and product politics and de-

termines the boundary conditions for the PCG (see Figure 2).

To enable the calculation of the Sustainability Values

each of the product options are associated with certain values

in all three sustainability dimensions. To determine the Total

Sustainability Score of one specific configuration the values

of all selected features will be summed up. The higher that

sum is the better is the result of a configuration. The values as

displayed in Figure 2 are mostly derived from results from a

pedelec assessment done by Neugebauer et al 2013. [19] Still,

these values have to be considered as fictive as the assessment

had been done for a specific network of producers and suppli-

ers and according to their production processes and methods.

For the PCG the basic implications from that assessment were

adopted, but a series of assumptions had to be made for the

different configuration options in order to simplify the scoring

system.

The Frames are the core feature of the pedelec. Hence,

they are the features providing the initial sustainability values.

Alternative Suppliers and Functional Features only modify

the initial sustainability values set by the frames and the de-

fault configuration. To determine the initial sustainability

values for the frame types, the following indicators were used:

a. Economic: Maintainability and Lifetime of the material

b. Environmental: Climate Change and Primary Energy

Demand related to material processing

c. Social: Labour Health conditions related to material pro-

cessing

To determine the Sustainability Value for each frame mate-

rial a comparison within the materials was applied for each

dimension and a value according to the material’s ranking was

set. The value ranges from one to four where four is best and

one is worst. If two materials are equal or have no significant

difference the same value is applied. In the economic dimen-

sion for example Bamboo is worst and gets the value one as it

has the shortest lifetime and is difficult to maintain. Stainless

Steel is significantly better and gets the value three. Alumini-

um and Titanium have the longest lifetime and are easy to

maintain. As both materials have no significant differences

they both get the value four.

The default configuration at the beginning of the PCG is a

pedelec with a Stainless Steel frame from Supplier B, a Stand-

ard Electric Motor and a Battery Type A. In that configuration

the pedelec has a Total Sustainability Scores of 3/2/2 (see

Figure 2). All modification values are determined in compari-

son to the features of the default configuration. If one option

deteriorates one of the sustainability values in one dimension

it gets a modification value of minus one in that dimension. If

it improves the sustainability value it gets a modification value

of plus one there. If the option has no effect on the sustainabil-

ity value it gets a modification value of zero.

For the three Suppliers the modification values of each

sustainability dimension depend on the following indicators:

a. Economic: Production Costs

b. Environmental: CO2-Emmsion due to transportation from

supplier to retailer (in Germany)

c. Social: Fairness of Salary

Supplier A is situated in Western Europe and has high pro-

duction costs and salaries but short transportation distance.

Supplier B is situated in Southern Europe and is the default

setting without modifications. Applying the value determina-

tion model mentioned before Supplier A gets the modification

values -1/0/1. Supplier A gets a -1 in the economic dimension

as it has higher production costs than Supplier B (default con-

figuration) due to higher salaries. At the same time the higher

salaries are better in terms of fairness of salary and result in a

+1 in the social dimension. In the environmental dimension

there are no significant differences between Supplier A and B

as the transportation distances from both supplier locations

(west and south Europe) are similar.

The third Supplier C is situated in Asia and has low pro-

duction costs and low salaries which are hardly enough for

living, but introduces a long transportation distance which

affects the environmental score. We assume that all three

suppliers are equally able to provide all types of frames. Addi-

tional effects on sustainability characteristics e.g. due to costs

and CO2-emissions caused by the transport of raw materials to

the supplier’s location are ignored.

For the Functional Features the modification values of

each sustainability dimension depend on the following indica-

tors:

a. Economic: Maintainability and Production Costs

b. Environmental: Primary Energy Demand and Energy

Efficiency

c. Social: Fairness of Salary

Figure 2: Table of predefined options with assigned scores

62 Wei Min Wang et al. / Procedia CIRP 26 ( 2015 ) 58 – 63

The features that affect the Sustainability Scores are the

Electric Motor with Regenerative Braking, the Battery Type

B, the Solar Panel and the two types of Computer Systems.

The Electric Motor with Regenerative Braking reduces energy

consumption during use of the pedelec but introduces higher

production cost and worse maintainability. The Battery Type

B increases efficiency but also introduces higher production

costs. The Computer Systems raise additional production

costs, but the Driver Assistance System uses gathered infor-

mation to optimize the electric drive support, controlling the

motor and giving the driver hints how to save energy reducing

the energy consumption of the pedelec. The Smartphone Con-

nector only displays information like speed, total distance

travelled and so on.

All relationships between the pedelec’s possible configura-

tions and the sustainability values described before are mod-

elled in an ontology (see Figure 1).

6. Course of the Product Configuration Game

The starting point is a web based Product Configurator (see

Figure 3). The PCG consists of two stages. At the beginning of

the first stage the product configurator will show a pedelec

configured with the default settings that has a Stainless Steel

frame from Supplier B, a Standard Electric Motor and a Bat-

tery of type A. In that stage the Sustainability Scores are hid-

den. The only hints the user has regarding the bicycle’s charac-

teristics are the product characteristics shown in the according

box in the lower right corner. Thus, the user has to configure

the pedelec based on this information and his instinct. This

simulates the fact that real product engineers also have only

limited prospective possibilities to assess the sustainability of

their products. Once the user is done with his changes he can

move on to the next stage by submitting his configuration.

Now the Sustainability Scores will be calculated and displayed

as diagrams. The user’s score will be saved and compared to

previous scores to show the user his ranking. In that stage the

user can alter his configuration freely while the sustainability

scores are calculated and displayed in real time. Additionally,

he can explore the reasons and relations that led to the score by

accessing the ontological trees through the questions mark

symbols behind each sustainability dimension. Finally, the user

can also leave a feedback about the PCG.

7. Discussion and outlook

Regarding commercial goods a clear framework is missing

that helps public audience to understand the complex delibera-

tions behind sustainable manufacturing. For non-experts the

inherent interdependencies of a product’s characteristics and

its sustainability performance throughout the PLC may not be

obvious or comprehensible [6]. As the willingness to spend

time on researching product characteristics is still limited

despite of growing awareness for sustainability, the absence of

available, comprehensible and reliable information may enable

deliberate misuse and lead to misunderstanding.

The proposed concept does not claim to represent the com-

plexity of modern value creation networks properly in that

stage. It is rather supposed to raise the awareness of public

audience for these underlying complexities of “Sustainability”

and motivate them to investigate the relationships of modern

value creation networks. Although the applied model of sus-

tainable manufacturing is a very simplified one, we believe

that the playful and interactive way in which the idea of sus-

tainability is presented can encourage people to think about

the products they use in their daily life and to explore the

consequences of their consume decisions. As the scores and

decisions of the users will be anonymously stored the collect-

ed data can be used to investigate whether the proposed con-

cept confirms the intended effect. Combined with the feed-

Figure 3: User interface of the Product Configurator Game

Wei Min Wang et al. / Procedia CIRP 26 ( 2015 ) 58 – 63

back of users those data can also help to find improvement

potentials for the PCG.

During the development of the PCG it became clear that

sustainability assessment is not “black or white” [19] as it was

needed for a clear scoring. In many cases sustainability indica-

tors are closely related to each other and cannot be treated

alone. Tradeoffs between the characteristics in the three di-

mensions are almost inevitable. The intended simplifications

regarding sustainability assessment need much more elabora-

tion to meet the scientific standard. For the further develop-

ment of the PCG results from the CRC1026 will be integrated

continuously. Therefore, the sustainability values and modifi-

cation values used in this paper should be regarded as first

drafts that will be refined progressively.

Acknowledgement

The research is funded by the DFG through the project

CRC1026 – “Sustainable Manufacturing - Shaping Global

Value Creation”. We thank all researchers of the CRC 1026

for sharing their expertise and for their contributions in the

ongoing process of ontology development. Especially, we

want to thank our colleagues from the Chair of Sustainable

Engineering of the TU Berlin. Their valuable contribution

allowed us to find scientific correct simplifications for the

complex topic of sustainability and to turn our idea into reali-

ty.

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