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arXiv · 2411.09935

Whole-Body Impedance Coordinative Control of Wheel-Legged Robot on Uncertain Terrain

Lei Shi·Xinghua Yu·Cheng Zhou·Wanxin Jin·Wanchao Chi·Shenghao Zhang·Dongsheng Zhang·Xiong Li·Zhengyou Zhang
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Abstract

This article propose a whole-body impedance coordinative control framework for a wheel-legged humanoid robot to achieve adaptability on complex terrains while maintaining robot upper body stability. The framework contains a bi-level control strategy. The outer level is a variable damping impedance controller, which optimizes the damping parameters to ensure the stability of the upper body while holding an object. The inner level employs Whole-Body Control (WBC) optimization that integrates real-time terrain estimation based on wheel-foot position and force data. It generates motor torques while accounting for dynamic constraints, joint limits,friction cones, real-time terrain updates, and a model-free friction compensation strategy. The proposed whole-body coordinative control method has been tested on a recently developed quadruped humanoid robot. The results demonstrate that the proposed algorithm effectively controls the robot, maintaining upper body stability to successfully complete a water-carrying task while adapting to varying terrains.

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Lei Shi, Xinghua Yu, Cheng Zhou, Wanxin Jin, Wanchao Chi, Shenghao Zhang, Dongsheng Zhang, Xiong Li, Zhengyou Zhang. 2024-11-15. Whole-Body Impedance Coordinative Control of Wheel-Legged Robot on Uncertain Terrain. https://arxiv.org/abs/2411.09935

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