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arXiv · 1208.6289

Lift-off dynamics in a simple jumping robot

Jeffrey Aguilar·Alex Lesov·Kurt Wiesenfeld·Daniel I. Goldman
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Abstract

We study vertical jumping in a simple robot comprising an actuated mass-spring arrangement. The actuator frequency and phase are systematically varied to find optimal performance. Optimal jumps occur above and below (but not at) the robot's resonant frequency $f_0$. Two distinct jumping modes emerge: a simple jump which is optimal above $f_0$ is achievable with a squat maneuver, and a peculiar stutter jump which is optimal below $f_0$ is generated with a counter-movement. A simple dynamical model reveals how optimal lift-off results from non-resonant transient dynamics.

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Jeffrey Aguilar, Alex Lesov, Kurt Wiesenfeld, Daniel I. Goldman. 2012-08-30. Lift-off dynamics in a simple jumping robot. https://doi.org/10.1103/physrevlett.109.174301

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