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arXiv · 2411.00347

An Untethered Bioinspired Robotic Tensegrity Dolphin with Multi-Flexibility Design for Aquatic Locomotion

Luyang Zhao·Yitao Jiang·Chun-Yi She·Mingi Jeong·Haibo Dong·Alberto Quattrini Li·Muhao Chen·Devin Balkcom
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Abstract

This paper presents the first steps toward a soft dolphin robot using a bio-inspired approach to mimic dolphin flexibility. The current dolphin robot uses a minimalist approach, with only two actuated cable-driven degrees of freedom actuated by a pair of motors. The actuated tail moves up and down in a swimming motion, but this first proof of concept does not permit controlled turns of the robot. While existing robotic dolphins typically use revolute joints to articulate rigid bodies, our design -- which will be made opensource -- incorporates a flexible tail with tunable silicone skin and actuation flexibility via a cable-driven system, which mimics muscle dynamics and design flexibility with a tunable skeleton structure. The design is also tunable since the backbone can be easily printed in various geometries. The paper provides insights into how a few such variations affect robot motion and efficiency, measured by speed and cost of transport (COT). This approach demonstrates the potential of achieving dolphin-like motion through enhanced flexibility in bio-inspired robotics.

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Luyang Zhao, Yitao Jiang, Chun-Yi She, Mingi Jeong, Haibo Dong, Alberto Quattrini Li, Muhao Chen, Devin Balkcom. 2024-11-01. An Untethered Bioinspired Robotic Tensegrity Dolphin with Multi-Flexibility Design for Aquatic Locomotion. https://arxiv.org/abs/2411.00347

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