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arXiv · 2403.10955

Agonist-Antagonist Pouch Motors: Bidirectional Soft Actuators Enhanced by Thermally Responsive Peltier Elements

Trevor Exley·Rashmi Wijesundara·Nathan Tan·Akshay Sunkara·Xinyu He·Shuopu Wang·Bonnie Chan·Aditya Jain·Luis Espinosa·Amir Jafari
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Abstract

In this study, we introduce a novel Mylar-based pouch motor design that leverages the reversible actuation capabilities of Peltier junctions to enable agonist-antagonist muscle mimicry in soft robotics. Addressing the limitations of traditional silicone-based materials, such as leakage and phase-change fluid degradation, our pouch motors filled with Novec 7000 provide a durable and leak-proof solution for geometric modeling. The integration of flexible Peltier junctions offers a significant advantage over conventional Joule heating methods by allowing active and reversible heating and cooling cycles. This innovation not only enhances the reliability and longevity of soft robotic applications but also broadens the scope of design possibilities, including the development of agonist-antagonist artificial muscles, grippers with can manipulate through flexion and extension, and an anchor-slip style simple crawler design. Our findings indicate that this approach could lead to more efficient, versatile, and durable robotic systems, marking a significant advancement in the field of soft robotics.

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Trevor Exley, Rashmi Wijesundara, Nathan Tan, Akshay Sunkara, Xinyu He, Shuopu Wang, Bonnie Chan, Aditya Jain, Luis Espinosa, Amir Jafari. 2024-03-16. Agonist-Antagonist Pouch Motors: Bidirectional Soft Actuators Enhanced by Thermally Responsive Peltier Elements. https://doi.org/10.1109/iros58592.2024.10802253

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