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arXiv · 2006.09921

Approximate Simulation for Template-Based Whole-Body Control

Vince Kurtz·Patrick M. Wensing·Hai Lin
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Abstract

Reduced-order template models are widely used to control high degree-of-freedom legged robots, but existing methods for template-based whole-body control rely heavily on heuristics and often suffer from robustness issues. In this letter, we propose a template-based whole-body control method grounded in the formal framework of approximate simulation. Our central contribution is to demonstrate how the Hamiltonian structure of rigid-body dynamics can be exploited to establish approximate simulation for a high-dimensional nonlinear system. The resulting controller is passive, more robust to push disturbances, uneven terrain, and modeling errors than standard QP-based methods, and naturally enables high center of mass walking. Our theoretical results are supported by simulation experiments with a 30 degree-of-freedom Valkyrie humanoid model.

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Vince Kurtz, Patrick M. Wensing, Hai Lin. 2020-06-17. Approximate Simulation for Template-Based Whole-Body Control. https://arxiv.org/abs/2006.09921

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