基于三维视觉的焊接机器人轨迹跟踪

3-D vision-based trajectory tracking of welding robots

为改善激光焊接机器人的运动轨迹精度,提出一种基于视觉的机器人轨迹跟踪控制方法。该方法将摄像机安装于工业机器人末端构成视觉反馈的控制系统,采用阈值分割方法检测出激光焦点,利用灰度投影积分方法快速检测出焊缝线,然后以修正的线-线匹配和立体视觉技术计算出激光焦点和焊缝线的空间位置,得到激光焦点相对于焊缝线的误差,再结合机器人运动学原理控制机器人实时运动以消除此误差。实验结果表明该方法能够有效提高机器人轨迹精度。

The trajectory accuracy of laser welding robots is improved by a robot trajectory tracking method using a robot control system based on visual feedback through two cameras mounted on the end of an industrial robot. A threshold segmentation method is used to find the laser focus and a gray projecting integral method is used to quickly detect weld seam. Then a modified line-line matching method and stereo vision technologies are used to calculate the laser focus and weld seam positions and the error between the laser focus and the weld seam. The robot then moves to reduce the error as soon as possible based on the robot kinematics. Test results show that the method effectively improves the trajectory accuracy of industrial robots.