Image Measurement on Curvature Around Seam Line for Motion Control of Laser Welding Robot

Abstract

Automating robot laser welding requires that the laser irradiation direction and laser focus positioning influencing welding strength are controlled precisely. Since the edge of the welded object can be transformed on processing by such as cutting, bending and grinding, the direct measurement is necessary to control the laser irradiation. Especially, the information of the curvature around the seam line is important because the precision influences the molten direction. The image measurement for curvatures around the seam line derives a three-dimensional approximation of the welded object’s curved surface from core-lines of images of the laser for measurement. By results of experiments the effectiveness and the limitations of our proposal are demonstrated.