A Sustainable Development Framework for Soft Pneumatic Actuators that are: Biodegradable, Self-healable and Re-programmable

Engineers and roboticists have long been acquainted with the irreversible design-to-fabrication process, where the transition from design to final production is completed in a single, uninterrupted workflow. Despite the well-recognized benefits of this approach, there is an increasing focus on sustainable, eco-friendly, and iterative development frameworks that prioritize biodegradation, reusability, and self-resilience. In response to this evolving landscape, this article presents a novel approach for developing soft pneumatic actuators aligned with sustainability goals. This is achieved through two key features: (1) The soft body is fabricated using biodegradable and self-healing hydrogel materials, primarily composed of Konjac Glucomannan, Gelatin, and Borax; (2) Instead of restarting the costly design-to-fabrication process when the robot’s requirements change, we propose reprogramming the actuator’s behavior by selectively introducing air blockers, made from environmentally friendly materials (Gelatin and Borax). Furthermore, this reprogrammable feature is iterative, leveraging the reversible gelation process, which allows for the extraction of liquid-form air blockers from the soft body, i.e., enabling reconfiguration. To demonstrate the feasibility and versatility of this design strategy, we applied it to a PneuNet soft actuator as a proof of concept, showcasing its ability to achieve varied actuation capabilities. Additionally, the mechanical properties and self-healing characteristics of the composite material were experimentally investigated. This study is expected to contribute to the growing trend of sustainability in soft robotics research.