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arXiv · 2609.31880

Efficient Bezier Velocity Optimization for Free-Floating Space Manipulators

Duo Zhang·Zhizhuo Zhang·Xiaoli Bai·Jingjin Yu
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Abstract

We present FAVOR (Free-floating Arm Velocity Optimization with Recursive Sensitivities), a planner for collision-free reaching, tracking, and prescribed-time pre-grasp interception on an unactuated spacecraft. It optimizes Bezier joint-velocity curves with linear velocity, acceleration, and continuity constraints. Decision dimension is independent of rollout resolution. Analytical recursive sensitivities provide task and clearance gradients through the coupled base-arm motion. Parallel evaluation, caching, and incremental collision discovery reduce computation. With a seven-DoF arm and five simulated spacecraft models, FAVOR achieves 99.8% point-to-point success with 1.779 s mean computation, versus 62.9% and 50.270 s for an IK-initialized position-spline baseline. Means include failures and timeouts. FAVOR completes 30 of 36 tracking cases, versus 15 for single-step QP, and all 36 interception instances, versus 22 for the spline baseline. A controlled ablation shows that finite differences increase mean planning time 4.7-fold.

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Duo Zhang, Zhizhuo Zhang, Xiaoli Bai, Jingjin Yu. 2026-09-25. Efficient Bezier Velocity Optimization for Free-Floating Space Manipulators. https://arxiv.org/abs/2609.31880

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