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arXiv · 2412.13196

ExBody2: Advanced Expressive Humanoid Whole-Body Control

Mazeyu Ji·Xuanbin Peng·Fangchen Liu·Jialong Li·Ge Yang·Xuxin Cheng·Xiaolong Wang
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Abstract

This paper tackles the challenge of enabling real-world humanoid robots to perform expressive and dynamic whole-body motions while maintaining overall stability and robustness. We propose Advanced Expressive Whole-Body Control (Exbody2), a method for producing whole-body tracking controllers that are trained on both human motion capture and simulated data and then transferred to the real world. We introduce a technique for decoupling the velocity tracking of the entire body from tracking body landmarks. We use a teacher policy to produce intermediate data that better conforms to the robot's kinematics and to automatically filter away infeasible whole-body motions. This two-step approach enabled us to produce a student policy that can be deployed on the robot that can walk, crouch, and dance. We also provide insight into the trade-off between versatility and the tracking performance on specific motions. We observed significant improvement of tracking performance after fine-tuning on a small amount of data, at the expense of the others.

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Mazeyu Ji, Xuanbin Peng, Fangchen Liu, Jialong Li, Ge Yang, Xuxin Cheng, Xiaolong Wang. 2024-12-17. ExBody2: Advanced Expressive Humanoid Whole-Body Control. https://arxiv.org/abs/2412.13196

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