Controlled Locomotion of a Minimal Soft Structure by Stick-Slip Nonlinearity

TL;DR

This paper introduces a novel soft structure locomotion mechanism utilizing stick-slip nonlinearities and internal resonance, enabling controlled multi-modal movement through harmonic excitation.

Contribution

It demonstrates a new method for soft structure locomotion leveraging stick-slip transitions and internal resonance to achieve controlled, multi-modal movement.

Findings

Validated relation for motion acceleration threshold.

Discovered velocity inversion near resonance.

Achieved controlled multi-modal motion.

Abstract

We present a locomotion mechanism that uses the stick-slip transition of a soft passive structure with an internal mechanical resonance. The structure is harmonically driven by a global vertical shaking and, because of its resonance dephasing and the threshold response of stick-slip transition, it can either move forward or backward. We establish a relation for the motion acceleration threshold that we experimentally validate. We identify a non-trivial regime close to the resonance with a velocity inversion for a constant excitation frequency and an increasing driving amplitude. We finally show that we can achieve a controlled multi-modal motion by combining multiple internal resonances.