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arXiv · 2609.25486

Brace Yourself: Task-Conditioned Environmental Bracing for Forceful Humanoid Manipulation

Zongyuan Zhang·Christopher Lehnert·Will N. Browne·Jonathan M. Roberts
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Abstract

Forceful manipulation is challenging for humanoid robots because interaction forces can disturb whole-body balance. We introduce the Supporting Hand Strategy (SHS), which enables a humanoid to brace against the environment with one hand while performing forceful manipulation with the other. SHS optimises a task-conditioned support configuration that guides two synchronous reinforcement-learning policies, without human motion data or online whole-body trajectory planning. On a Unitree G1, SHS achieved usable contact forces up to 60 N, compared with a maximum sustained force of 13.5 N without environmental bracing, while substantially improving force tracking over a task-independent support configuration. The same policies generalised to different task regions without retraining. SHS therefore provides a simple mechanism for substantially extending humanoid forceful-manipulation capability.

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Zongyuan Zhang, Christopher Lehnert, Will N. Browne, Jonathan M. Roberts. 2026-09-21. Brace Yourself: Task-Conditioned Environmental Bracing for Forceful Humanoid Manipulation. https://arxiv.org/abs/2609.25486

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