基于手眼立体视觉的弧焊机器人平面工件定位系统

Locating system for planar workpiece based on hand-eye stereo vision in arc welidng robot

在工业生产中应用的焊接机器人都是示教再现式的机器人 ,在批量生产时这种机器人要求每次工件定位必须一致 ,否则需要重新示教 ;带有离线编程系统的机器人同样存在工件定位问题 ,如果工件定位不准 ,焊接机器人无法按原离线编程系统生成的路径完成焊接。作者针对平面工件开发了一套基于手眼立体视觉的弧焊机器人工件定位系统 ,首先对摄像机的内外参数和机器人手眼关系进行标定 ;然后控制机器人运动 ,使安装在机器人末端的摄像机在两个不同的位置取像 ;最后通过图像处理和立体视觉的方法来计算出平面工件在机器人基坐标系中的三维信息。试验表明该系统获取的工件定位信息精确。

Arc welding robots applied in the industrial production all are the teaching and playback robots.This robot requests that the workpiece is located conformably every time in the instance of the batch quantity production,otherwise teaching is requested over againg.Also there is locating problem in arc wedling robot with off-line program system.If the workpiece is located inaccurately,arc welding robot can’t finish welding along the original track made by off-line program.In the paper,the locating system for planar workpiece based on hand-eye stereo vision in arc welding robot is developed.First the inside and outside parameters of the camera and the hand-eye relation are calibrated.And then the robot is controlled and moved to the two positions.The images are captured by the camera mounted in the end effector of the robot at the two positions.Finally the workpiece’s 3D coordinates in the basal coordinate of the robot are calculated by image processing and stereo vision.Experiments show that the workpiece’s locating information got by locating system is accuracy.The locating system laid the foundation of independent welding.