Spatiotemporal Calibration for Laser Vision Sensor in Hand-Eye System Based on Straight-Line Constraint
Peiwen Yang, Mingquan Jiang, Xinyue Shen, Heping Zhang
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://github.com/RoboticsPolyu/LVS_ST_CALIB.
BibTeX
@inproceedings{ral2025_spatiotemporalca,
title = {Spatiotemporal Calibration for Laser Vision Sensor in Hand-Eye System Based on Straight-Line Constraint},
author = {Peiwen Yang and Mingquan Jiang and Xinyue Shen and Heping Zhang},
booktitle = {RA-L 2025},
year = {2025}
}