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arXiv · 1908.08645

Robust Navigation of a Soft Growing Robot by Exploiting Contact with the Environment

Joseph D. Greer·Laura H. Blumenschein·Ron Alterovitz·Elliot W. Hawkes·Allison M. Okamura
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Abstract

Navigation and motion control of a robot to a destination are tasks that have historically been performed with the assumption that contact with the environment is harmful. This makes sense for rigid-bodied robots where obstacle collisions are fundamentally dangerous. However, because many soft robots have bodies that are low-inertia and compliant, obstacle contact is inherently safe. As a result, constraining paths of the robot to not interact with the environment is not necessary and may be limiting. In this paper, we mathematically formalize interactions of a soft growing robot with a planar environment in an empirical kinematic model. Using this interaction model, we develop a method to plan paths for the robot to a destination. Rather than avoiding contact with the environment, the planner exploits obstacle contact when beneficial for navigation. We find that a planner that takes into account and capitalizes on environmental contact produces paths that are more robust to uncertainty than a planner that avoids all obstacle contact.

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Joseph D. Greer, Laura H. Blumenschein, Ron Alterovitz, Elliot W. Hawkes, Allison M. Okamura. 2021-02-09. Robust Navigation of a Soft Growing Robot by Exploiting Contact with the Environment. https://doi.org/10.1177/0278364920903774

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