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arXiv · 2605.10696

VRA: Grounding Discrete-Time Joint Acceleration in Voltage-Constrained Actuation

Lingwei Zhang·Jiaming Wang·Tianlin Zhang·Zhitao Song·Xuanqi Zeng·Weipeng Xia·Zhongyu Li·Yun-hui Liu
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Abstract

Discrete-time joint acceleration constraints are widely used to enforce position and velocity limits. However, under voltage-constrained electric actuators, kinematically admissible accelerations may be physically unrealizable, exposing a missing execution-level abstraction. We propose Voltage-Realizable Acceleration (VRA), a joint-level acceleration interface that grounds kinematic acceleration in voltage-constrained actuator physics by restricting commanded accelerations to voltage-realizable constraints. Hardware experiments on electric actuators and a wheel-legged quadruped show that VRA removes unrealizable accelerations, restores consistent near-constraint execution, and reduces constraint-induced oscillations.

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Lingwei Zhang, Jiaming Wang, Tianlin Zhang, Zhitao Song, Xuanqi Zeng, Weipeng Xia, Zhongyu Li, Yun-hui Liu. 2026-05-11. VRA: Grounding Discrete-Time Joint Acceleration in Voltage-Constrained Actuation. https://arxiv.org/abs/2605.10696

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