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arXiv · 2412.07343

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

Thomas Barois·A. Boucherie·L. Tadrist·H. Kellay
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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.

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Thomas Barois, A. Boucherie, L. Tadrist, H. Kellay. 2024-12-10. Controlled Locomotion of a Minimal Soft Structure by Stick-Slip Nonlinearity. https://doi.org/10.1103/physrevlett.133.238301

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