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arXiv · 2605.21398

From swept contact to pose: Probe-aware registration via complementary-shape docking

Chen Chen·Yunwen Li·Yifan Xu·Xiangjie Yan·Chang Shu·Jianxia Hou·Shiji Song·Xiang Li
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Abstract

Accurate registration between a prior model and the real scene is essential for high-precision robotic manipulation, yet optical methods suffer from long calibration chains, line-of-sight constraints, and fabrication errors. We propose a calibration-free alternative that reformulates contact registration as complementary-shape docking between the object and the probe's swept volume, explicitly accounting for probe geometry and leveraging both contact and non-contact evidence. Our solver integrates a global-to-local search via 3D FFT correlation over low-discrepancy SO(3) samples, then followed by continuous SE(3) refinement using Lie-algebra updates and analytic contact sensitivities. This pipeline yields efficient exploration and metric-grade convergence without fragile point correspondences. Simulation across free-form meshes achieved sub-0.04 mm and sub-0.4{\deg} accuracy and robustness to pose noise and contact loss. On a tooth-preparation robot, our method attained 0.42 mm and 3.75{\deg}, outperforming an optical tracker registration while requiring no external sensors. These results demonstrate a practical and precise registration strategy for surgical and industrial robots.

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Chen Chen, Yunwen Li, Yifan Xu, Xiangjie Yan, Chang Shu, Jianxia Hou, Shiji Song, Xiang Li. 2026-05-20. From swept contact to pose: Probe-aware registration via complementary-shape docking. https://arxiv.org/abs/2605.21398

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