Pre-stressed Bi-stable Hair Clip Mechanism for Faster Swimming Robots

TL;DR

This paper introduces a novel in-plane prestressed mechanism inspired by hair clips, which leverages structural instability to improve the performance of swimming robots and soft grippers.

Contribution

It presents a new in-plane prestressed actuator design that harnesses buckling and snap-through phenomena for enhanced soft robotics applications.

Findings

Enables faster swimming in underwater robots.

Improves soft gripper performance.

Provides analysis of buckling energy landscapes.

Abstract

Structural instability is a hazard that leads to catastrophic failure and is generally avoided through special designs. A trend, however, has emerged over the past decades pointing to the harnessing of mechanisms with instability. Inspired by the snapping of a hair clip, we are finessing the unique characteristics of the lateral-torsional buckling of beams and the snap-through of pre-buckled dome-like thin-wall structures in a new field: the in-plane prestressed mechanism. Analyses reveal how the 2D-3D assembly of an in-plane prestressed actuator (IPA) is achieved and how the post-buckling energy landscape is pictured. Combining them with soft robotics, we show that the inclusion of a bistable IPA can enormously enhance the performance of an underwater fish robot as well as inspire a finger-like soft gripper.