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arXiv · 2409.09203

Pinto: A latched spring actuated robot for jumping and perching

Christopher Y. Xu·Jack Yan·Justin K. Yim
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Abstract

Arboreal environments challenge current robots but are deftly traversed by many familiar animal locomotors such as squirrels. We present a small, 450 g robot "Pinto" developed for tree-jumping, a behavior seen in squirrels but rarely in legged robots: jumping from the ground onto a vertical tree trunk. We develop a powerful and lightweight latched series-elastic actuator using a twisted string and carbon fiber springs. We consider the effects of scaling down conventional quadrupeds and experimentally show how storing energy in a parallel-elastic fashion using a latch increases jump energy compared to series-elastic or springless strategies. By switching between series and parallel-elastic modes with our latched 5-bar leg mechanism, Pinto executes energetic jumps as well as maintains continuous control during shorter bounding motions. We also develop sprung 2-DoF arms equipped with spined grippers to grasp tree bark for high-speed perching following a jump.

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Christopher Y. Xu, Jack Yan, Justin K. Yim. 2024-09-13. Pinto: A latched spring actuated robot for jumping and perching. https://arxiv.org/abs/2409.09203

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