焊接机器人工具坐标系标定的研究与实现

Study and Realization of Tool Coordinate Frame Calibration for Welding Robots

采用六点标定法对工具坐标系进行标定.首先标定工具参数的位置向量,其次标定工具坐标系的姿态矩阵,其中工具中心点位置标定采用线性最小二乘法的矩阵形式进行求解,工具坐标系姿态采用向量和矩阵的基本运算进行求解.针对RB_1400六自由度焊接机器人,基于开放式软件平台CODESYS开发了工具坐标系标定算法模块和焊枪位姿变换模块,最后以此为基础移动机器人对准基准点,测试分别绕x、y、z轴旋转检查TCP点的位置是否符合要求.结果表明:该方法确实可行,并且可以适用于其他类型机器人的工具坐标系标定.

The tool coordinate system was calibrated according to six-point calibration method. First,it calibrated the position vector of the tool parameters,followed by calibration of orientation matrix of the tool coordinate system,which used the matrix form of the linear least squares to fit tool center point position and the basic operations of the vector and the matrix transformation to calculate tool coordinate frame orientation. For the RB_1400 six-DOF welding robot,the paper developed the tool coordinate system calibration algorithm module and the welding gun pose transformation module based on the automation software CODESYS. Finally,by executing a movement to the reference point,which uses the result data of the developed function block,the test checked whether TCP can meet the requirements when moving around the x,y,and z axis separately. Result shows that the method is feasible and can be also applied to other types of calibration of the robot tool coordinate system.