Fast Calibration for Robot Welding System with Laser Vision

Camera calibration and robot hand-eye calibration are important parts in applications of robots with visions. A way to simultaneously carry out camera calibration and robot hand-eye calibration is presented in robot welding system with laser vision. It is based on a certain relation between hand-eye matrix and matrix of robot hand frame to robot base frame. Calibration experiments are performed in this way using specifically designed calibration objects. And all parameters to be calibrated are solved out in nonlinear least square optimization method. 3D world coordinates of 20 sample points selected from a v-groove seam are reconstructed with the calibration results. By contrasting their real coordinates, average error is 0.12 mm, which is sufficient to the requirement of robot seam tracking.