Towards Green-Aware Assistive Robotics for Sustainable Rehabilitation at UNICAL

Towards Green-Aware Assistive Robotics for Sustainable Rehabilitation at UNICAL Simone Leone DIMEG - Department of Mechanical, Energy and Management Engineering University of Calabria Rende, Italy [email protected] Francesco Lago DIMEG - Department of Mechanical, Energy and Management Engineering University of Calabria Rende, Italy [email protected] Giuseppe Carbone DIMEG - Department of Mechanical, Energy and Management Engineering University of Calabria Rende, Italy [email protected] Abstract—This paper presents examples of green-aware assistive robotic solutions developed at University of Calabria addressing critical challenges in healthy aging and rehabilitation while minimizing environmental impact. Our systematic design methodology incorporates sustainability principles, producing innovative mechatronic devices including energy-efficient upper-limb rehabilitation systems, sustainable cable-driven exoskeletons, and low-power wheelchair-mounted feeding assistants. These solutions feature intuitive interfaces, energy-optimized telemonitoring, and adaptive green-aware control systems for clinical and home environments. Experimental validation demonstrates significant improvements in user engagement, motor function recovery, and quality of life while achieving up to 30% energy reduction compared to traditional systems. The approach combines advanced robotics with user-centered and environmentally conscious design principles, making assistive technologies more sustainable and accessible for elderly populations and individuals with disabilities. Keywords— Green-Aware, Assistive Robotics, Sustainable Rehabilitation, Mechatronic Design, Energy-Efficient I. INTRODUCTION The global aging population presents unprecedented challenges for healthcare systems, with over 771 million people aged 65+ worldwide requiring innovative solutions for maintaining independence and quality of life. Traditional rehabilitation approaches often face limitations in personalization, accessibility, long-term adherence, and environmental sustainability, creating a critical need for green-aware assistive technologies [1]. The World Health Organization emphasizes that assistive technologies should enhance functioning and promote wellbeing across diverse populations while considering environmental impact. In alignment with UN Sustainable Development Goals (SDGs 3, 9, 12), our research group at UNICAL has developed a comprehensive portfolio of green-aware assistive robotic solutions that address these challenges through systematic design methodologies, user-centered approaches, and environmentally conscious principles. This paper presents our latest developments in sustainable assistive robotics, focusing on two main areas: energy-efficient upper-limb rehabilitation and environmentally responsible daily living support systems. These solutions illustrate how modern green-aware robotics can be seamlessly integrated into healthcare workflows while ensuring cost-effectiveness, user accessibility, and environmental sustainability. II. GREEN-AWARE SYSTEMATIC DESIGN METHODOLOGY Our design process follows a systematic methodology structured in six sequential phases, integrating rigorous mathematical modeling, numerical simulation, experimental validation, and sustainability assessment. This approach ensures that every design decision considers both demonstrable theory and environmental impact, reducing integration problems and minimizing ecological footprint [3]. The methodology incorporates green-aware principles including energy efficiency through low-power electronics and optimized control algorithms, sustainable material selection (PLA, TPU, natural fiber composites), lifecycle assessment, and circular design strategies. Material selection balances sustainability with clinical requirements considering durability and safety standards. Future AI integration will employ edge computing and model compression to maintain energy efficiency. The framework progresses through sustainable concept generation, mathematical modeling, parametric CAD prototyping with virtual simulations predicting energy consumption, and experimental validation ensuring functional and sustainability goals. This systematic approach has proven effective across diverse applications, shortening development time, minimizing environmental footprint, and facilitating multidisciplinary collaboration in the evolving robotics landscape [3]. III. INNOVATIVE GREEN-AWARE SOLUTIONS Examples of assistive robotic solutions are shown in Figure 1. They address various rehabilitation needs through specifically designed sustainable mechatronic systems. (a) (b) (c) (d) Fig. 1. Overview of the assistive robotic devices developed: (a) Adiutor home rehabilitation system [4]; (b) Upper limb exoskeleton; (c) Pick&Eat Wheelchair-Mounted Robotic Arm; (d) ReHArm System The Adiutor system (Fig.1.a) is a home-based platform based on parallel delta architecture enabling safe upper-limb exercises with optimized energy consumption. It features energy-optimized performance evaluation, compressed data telemonitoring, modular recyclable PLA design, and lowpower e-ink display. The architecture prioritizes portability and component recycling [4]. The cable-driven exoskeleton (Fig.1.b) provides modular rehabilitation for elbow, wrist, and finger mobility using sustainable materials. The back-mounted motor assembly connects via lightweight recycled PLA modules reducing limb loading. Design features include bio-based TPU backplate 2025 I-RIM Conference October 17-19, Rome, Italy ISBN: 9788894580570 10.5281/zenodo.17629756 127 with seven servomotors featuring regenerative braking and energy-aware control (IMU, Kalman filtering, PID) for smooth execution [5]. The Pick&Eat platform (Fig.1.c) provides autonomous feeding assistance using green-aware design principles. Its modular architecture features interchangeable end-effectors manufactured from compostable bio-plastics via 3D printing with recycled filaments. Strategic sensor integration (forcesensing resistors, proximity detection) enables safe manipulation. Energy-optimized inverse kinematics with adaptive power modes reduce caregiver workload [6]. The ReHArm system (Fig.1.d) is a 5-DOF platform incorporating Variable Stiffness Joints with energy-efficient actuation dynamically adjusting resistance to patient needs. Green-aware innovations include piezoelectric energyharvesting sensors, adaptive algorithms optimizing energy profiles, and recyclable aluminum-PLA design. The A.R.M.S.minterface structures therapy into progressive stages adapting complexity based on real-time performance evaluation [7]. IV. RECENT EXPERIMENTAL VALIDATION Table I compares updated green-aware designs against original versions of the same devices [4-7]. "Original version" refers to first laboratory prototypes before implementing green-aware improvements (Section II). Percentage variations represent improvements (positive) or reductions (negative for energy, setup time, material impact) as: Δ = [(updated - original)/original] × 100%. Recent experimental studies conducted on our devices demonstrate significant improvements in terms of engagement, motor functionality, and sustainability. Table I presents the performance parameters obtained by comparing the updated systems with the original versions. TABLE I. COMPREHENSIVE VALIDATION RESULTS Metrics Devices Adiutor Cable Exos Pick&Eat ReHArm User Engagement +4% Maintained +3% +4% Motor Function +4% +3% Enhanced autonomy +6% Setup Efficiency -37% -33% -30% -20% Energy Consuption -22% -30% -25% -28% Material Impact -35% -40% -30% -38% All platforms achieve substantial environmental benefits including average 26% energy savings compared to original versions, 35% material footprint reduction through sustainable design incorporating recyclable and bio-based materials, and 40% carbon footprint reduction with enhanced recycling capabilities through modular architectures. Specific improvements include: Adiutor features upgraded energy-efficient motors with optimized control reducing idle consumption; modular design enables component replacement and recycling. Cable Exoskeleton uses recycled PLA modules with triangular structures improving efficiency and comfort; bio-based TPU backplate enables better anatomical adaptation. Pick&Eat employs optimized endeffectors via 3D printing with recycled filaments reducing material usage; enhanced integration enables efficient motion planning. ReHArm implements energy-efficient stiffness modulation; A.R.M.S. interface minimizes processing overhead while responding to patient progression. All systems reduced supervisory burden without compromising efficacy. Laboratory validation demonstrates technical feasibility and potential benefits of the green-aware approach, suggesting promising directions for accessible, environmentally friendly rehabilitation solutions. Further clinical validation with larger diverse populations is necessary to assess real-world effectiveness and long-term outcomes. V. CONCLUSIONS AND FUTURE DIRECTIONS Our comprehensive green-aware assistive robotics approach demonstrates the feasibility of integrating environmental sustainability with assistive technology development. The systematic design methodology combining user-centered principles with sustainable mechatronic solutions has produced devices that address key challenges while maintaining clinical functionality and minimizing environmental impact. Current limitations include validation confined to laboratory studies with limited samples, requiring future large-scale clinical trials across diverse populations. Long-term durability assessment of sustainable materials under intensive usage requires extended evaluation. Material selection criteria need further investigation to characterize clinical safety standards and lifecycle performance.Future developments focus on: (i) AI integration employing edge computing for personalized therapy; (ii) energy-efficient telemonitoring for remote management; (iii) sustainable manufacturing with circular economy principles; (iv) largescale clinical validation. International collaborations will expand assessment maintaining environmental standards, positioning these innovations toward sustainable technologysupported aging and rehabilitation. ACKNOWLEDGMENT This work was supported by the PNRR “FAIR” project: “Development of green-aware methodologies for the design and use of innovative robots” (CUP H23C22000860006), funded by the Italian Ministry of University and Research (MUR) under the National Recovery and Resilience Plan, Mission 4, Component 2, Investment 1.3— NextGenerationEU. REFERENCES [1] A. Guatibonza, L. Solaque, A. Velasco, et al., Assistive Robotics for Upper Limb Physical Rehabilitation: A Systematic Review and Future Prospects, Chinese Journal of Mechanical Engineering 37 (2024): 69. [2] J. Owuor, F. Larkan, B. Kayabu, et al., Does Assistive Technology Contribute to Social Inclusion for People with Intellectual Disability? A Systematic Review Protocol, BMJ Open 8 (2018): e017533. [3] S. Leone, F. Lago, D. Pisla, G. Carbone, A Systematic Approach for Robotic System Development, Technologies 13 (2025): 316. [4] E. M. Curcio, G. Carbone, Mechatronic Design of a Robot for Upper Limb Rehabilitation at Home, Journal of Bionic Engineering 18 (2021): 857–871 [5] G. Lavia et al., Design and Development of a Cable Exoskeleton for Elbow Rehabilitation, in New Trends in Medical and Service Robotics, Mechanisms and Machine Science, vol. 186 (2025). [6] S. Leone, L. Giunta, V. Rino, S. Mellace, A. Sozzi, F. Lago, E. M. Curcio, D. Pisla, G. Carbone, Design of a wheelchair-mounted robotic arm for feeding assistance of upper-limb impaired patients, Robotics 13 (2024) 38. [7] S. Leone, M. A. Laribi, E. Castillo-Castañeda, G. Carbone, An interactive combined mechatronic approach to enhance upper limb rehabilitation, in: Advances in Italian Mechanism Science, Springer Nature Switzerland, Cham, 2024, pp. 19–26 128