Automatic Teaching of 3-D Butt Joint for Laser Welding using the Machine Vision

To improve the accuracy and efficiency of laser welding for large-scale thin sheet, an automatic teaching method based on laser vision sensor was proposed. Through homogeneous coordinate transformation, kinematic models of multi-axis laser welding machine tool for the measuring device and torch were established respectively. Based on forward kinematics of the measuring device and inverse kinematics of the torch, seam information acquired by the machine vision were converted into every translational and rotational axis's motion (expressed as G codes), then automatic teaching was realized. Experimental results demonstrate the effectiveness of the proposed method.