基于特征线重合的测量系统与机器人坐标系对齐方法

Alignment Method of Measuring System and Robot Coordinate System Based on Feature Line Coincidence

为了提高测量过程中测量系统与机器人之间坐标系转换的精度,结合机器人的结构特点,提出了一种基于特征线重合的坐标转换方法。针对激光跟踪仪测量的坐标数据,求解坐标点云最小闭包球,同时在两个不同的坐标系下的点云中提取对应的特征线。根据空间几何关系,通过一系列的旋转和平移变换使特征线对应重合。利用矩阵变换理论得到变换矩阵,实现坐标系的转换。实验结果表明:相对于一些随机点多点拟合坐标系转换方法,该方法X、Y、Z方向的综合e_(RMS)误差仅为0.2829 mm,综合误差降低超过了10%。该坐标系转换方法可有效提高坐标系转换精度,提升工业机器人测量过程中坐标系的转换精度。

In order to improve the accuracy of coordinate system conversion between the measurement system and the robot during the measurement process,combined with the structural characteristics of the robot,a coordinate conversion method based on feature line coincidence is proposed.Aiming at the coordinate data measured by the laser tracker,the minimum closure sphere of the coordinate point cloud is solved,and the corresponding characteristic lines are extracted from the point cloud in two different coordinate systems.According to the spatial geometry,a series of rotations and transformations make the feature lines correspond to each other.The transformation matrix is obtained by using matrix transformation theory,and the transformation of coordinate system is realized.The experimental results show that compared with some random-point multi-point fitting coordinate system conversion methods,the comprehensive e_(RMS)error in the X,Y,and Z directions of this method is only 0.2829 mm.The combined error is reduced by more than 10%.This method can effectively improve the precision of coordinate system transformation,especially the precision of coordinate system transformation in the measurement process of industrial robots.