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

TL;DR

This paper introduces a bio-inspired, flexible, cable-driven dolphin robot with tunable design features, aiming to enhance aquatic locomotion by mimicking dolphin flexibility and muscle dynamics.

Contribution

It presents the first bio-inspired, flexible dolphin robot with a tunable skeleton and skin, advancing the design of soft aquatic robots for improved motion and efficiency.

Findings

Flexible tail improves swimming motion

Tunable skeleton affects speed and efficiency

Design is open-source and customizable

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.