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arXiv · 2509.12928

Spatiotemporal Calibration for Laser Vision Sensor in Hand-eye System Based on Straight-line Constraint

Peiwen Yang·Mingquan Jiang·Xinyue Shen·Heping Zhang
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Abstract

Laser vision sensors (LVS) are critical perception modules for industrial robots, facilitating real-time acquisition of workpiece geometric data in welding applications. However, the camera communication delay will lead to a temporal desynchronization between captured images and the robot motions. Additionally, hand-eye extrinsic parameters may vary during prolonged measurement. To address these issues, we introduce a measurement model of LVS considering the effect of the camera's time-offset and propose a teaching-free spatiotemporal calibration method utilizing line constraints. This method involves a robot equipped with an LVS repeatedly scanning straight-line fillet welds using S-shaped trajectories. Regardless of the robot's orientation changes, all measured welding positions are constrained to a straight-line, represented by Plucker coordinates. Moreover, a nonlinear optimization model based on straight-line constraints is established. Subsequently, the Levenberg-Marquardt algorithm (LMA) is employed to optimize parameters, including time-offset, hand-eye extrinsic parameters, and straight-line parameters. The feasibility and accuracy of the proposed approach are quantitatively validated through experiments on curved weld scanning. We open-sourced the code, dataset, and simulation report at https://anonymous.4open.science/r/LVS_ST_CALIB-015F/README.md.

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Peiwen Yang, Mingquan Jiang, Xinyue Shen, Heping Zhang. 2025-09-16. Spatiotemporal Calibration for Laser Vision Sensor in Hand-eye System Based on Straight-line Constraint. https://arxiv.org/abs/2509.12928

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