Research on quality inspection for backside weld of tailored blank laser welding based on texture feature

In tailored blank laser welding, the quality of backside weld has a significant influence on mechanical properties of tailored blanks. The conventional method for the quality inspection of weld seams is based on the structured light deformation. However, the structured light deformation is not obvious in the backside weld which with dust disturbance, so the extraction of feature points is difficult only based on the structured light. A quality inspection system for backside weld of tailored blank laser welding was built and a new method based on combination of texture feature and structured light was proposed in this paper. In this method, the textural feature of the image was firstly analyzed, and then the image was segmented by the difference of the image texture feature between the weld region and the base metal region; finally, the zone of the weld were recognized based on voting strategy and the feature points were extracted. Experiments were conducted with this method, then the considered weld width was detected and other weld defects could also be detected. The experiment results showed that the proposed inspection system and method were effective for backside weld quality inspection of tailored blanks laser welding.