Image Detection of Seam Line for Laser Welding Robot

Automating robot laser welding requires that laser irradiation direction and laser focus positioning influencing welding strength be controlled precisely along the seam line. Since the edge of the welded object can be transformed in processing by such as cutting, bending and grinding, direct measurement is necessary to detect the seam line. A robust image detection method of seam lines is proposed for hand-eye laser welding system equipped with an optical microscope, a CMOS camera and two slit lasers for measurement. The seam line is detected indirectly to utilize the difference between local and global distribution of image of measurement lasers. Results of experiments demonstrated the effectiveness of our proposal.