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arXiv · 2504.03988

Bistable SMA-driven engine for pulse-jet locomotion in soft aquatic robots

Graziella Bedenik·Antonio Morales·Supun Pieris·Barbara da Silva·John W. Kurelek·Melissa Greeff·Matthew Robertson
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Abstract

This paper presents the design and experimental validation of a bio-inspired soft aquatic robot, the DilBot, which uses a bistable shape memory alloy-driven engine for pulse-jet locomotion. Drawing inspiration from the efficient swimming mechanisms of box jellyfish, the DilBot incorporates antagonistic shape memory alloy springs encapsulated in silicone insulation to achieve high-power propulsion. The innovative bistable mechanism allows continuous swimming cycles by storing and releasing energy in a controlled manner. Through free-swimming experiments and force characterization tests, we evaluated the DilBot's performance, achieving a peak speed of 158 mm/s and generating a maximum thrust of 5.59 N. This work demonstrates a novel approach to enhancing the efficiency of shape memory alloy actuators in aquatic environments. It presents a promising pathway for future applications in underwater environmental monitoring using robotic swarms.

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Graziella Bedenik, Antonio Morales, Supun Pieris, Barbara da Silva, John W. Kurelek, Melissa Greeff, Matthew Robertson. 2025-04-04. Bistable SMA-driven engine for pulse-jet locomotion in soft aquatic robots. https://arxiv.org/abs/2504.03988

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