Digital Sheet Forming Technology And Experimental Research

With the development of intelligent manufacturing in recent years,the field of sheet metal stamping and forming has been developing from automation to intelligent.At present,in the forming process of sheet metal workpiece,the feeding method of sheet metal is mostly robot feeding.This feeding method requires a lot of teaching work to ensure the accuracy,and it has high requirements on the placement and shape of the sheet metal to be processed.At the same time in the plate forming process,high strength steel plate is prone to rupture,wrinkle and other defects.At present,it is commonly used to improve the forming performance by optimizing the shape of the drawing bar,and compensating the mold surface.But it takes a lot of time to test and repair the mold.In view of the above problems in feeding,this research uses the manipulator to combine the vision to complete the automatic feeding of the sheet metal stamping forming process.After relevant image processing and positioning algorithm,the robot can complete intelligent feeding.In view of the quality problem in sheet forming,the flexible variable blank holder force is proposed to form the workpiece.Firstly,based on the servo press,the blank holder control system is improved,and an independent loading intelligent control system with flexible variable blank holder force is proposed.Then,in the digital simulation,the cap workpiece is selected as the simulation object,the stamping simulation results of the cap workpiece under different fixed values and variable blank holder forces are analyzed,and the optimal blank holder force curve and the curve of the stamping load changing with time are obtained.The blank holder force curve is loaded into the control system,and the blank holder force and the punch load are controlled flexibly to adapt to the characteristics of different deformation stages of the parts.Through the research,the robot can position and feed the stamping plate based on vision.According to the optimized blank-holding curve,the drawing experiment was carried out on the control system loaded with variable blank-holding force,and it was proved that the proposed flexible blank-holding force stamping method can not only prevent the folding of the sheet metal from thinning,but also improve the drawing limit of the sheet metal.