Image Measurement on Curvature Around Seam Line for Motion Control of Laser Welding Robot
Akihiko Matsushita*, Takuya Hokari**, Shun’ichi Kaneko*,
Hitoshi Ohfuji***, and Kaoru Fukuda***
*Graduate School of Information Science and Technology, Hokkaido University, North 14 West 9, Sapporo 060-0814, Japan
**School of Engineering, Hokkaido University, North 14 West 9, Sapporo 060-0814, Japan
***SANKO-STEEL, Zenibako 3-515-1, Otaru-shi 047-0261, Japan
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.
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