On-machine Measurement and Compensation of Assembling Gap for 5-axis Friction Stir Welding based on 2D Laser Profilometer

Gap width control is an important task for friction stir welding (FSW) since assembling gap width greatly influences the welding quality. A new efficient method with on-machine measurement (OMM) system based on 2D laser profilometer has been developed in this paper. The method is divided into three steps. Firstly, kinematics and calibration are analyzed to establish the transform relationship from laser sensor coordinate system to workpiece coordinate system (WCS). Then, width information is obtained by an automatic recognition algorithm. Lastly, compensation strategy based on measurement results is presented. Experiments have been performed to verify the efficiency of the proposed compensation method. The results prove that the method is efficient in improving the accuracy and uniformity of assembling gap width.