Proposal of a bending anomaly estimation method in sequential press forming processes of sheets and its verification

Sequential press forming of thin sheets is a method in which different locations within single workpiece are pressed sequence, and used to manufacture large structures, such as storage tanks. In the sequential forming, it important estimate bending-defect areas efficiently because product shape can be corrected not by repairing dies but only re-pressing subsequent process. At present, high skill required determine they judged measuring gap from template. this study, versatile products obtained with proposed. Specifically, cosine similarity calculated between templates ideal shapes known defects prepared beforehand. A based on curvatures. Bending-defect then evaluated magnitude deviation average multiple similarities. This paper also presents procedure calculate threshold for estimating proposed method. The effectiveness was confirmed through case studies that considered virtual actual workpieces. It excess or deficiency bending even when local deformation measurement noise exist.