Car Cover Cad Model Reconstruction And Forming Simulation

With development of global economic integrity after entering WTO, the auto-industry of our country faces serious challenge. At present it is in urgent need to introduce advanced science and technology, especially the digital information technology, into research and development of auto-industry for establishment of key technology with independent knowledge property right to be lifted out of dependence of foreign enterprises and raise the innovative ability. Based on the above facts, present paper focused attention on comprehensive study of surface reverse reconstruction and CAE for forming process of automobile back boot inner panel in order to shorten the period of research and development for modern car, improve the quality of body cover panel and automobile in whole.To create finite element (FE) model for cover panel forming process, the reducing and noise eliminating process were employed in the point cloud of cover panel and its dies acquired by ATOS laser scan measuring system. Then, according to characteristics of cover panel forming process, CATIA modules created each surface of the CAD model through reverse and obverse method. Barlat's 3-parameter yield model and Belytschko-Tsay shell element were used for FE simulation according to characteristics of cover panel forming process and materials. Commercial FE software DYNAFORM was employed for FE simulation of CAD model. Elements with different size were used for the corner and smooth surface of dies. The element size for the blank was determined in the light of minimum dies fillet. The simulation results obtained by using DYNAFORM can reveal development course of the defects during body cover panel forming process and method to prevent the defects from occurrence was proposed based on the simulation results. The simulation results indicated that the primary factors that dominate the cover panel forming process are the bind mode, dimension and location of beads, shape and dimension of the blank. The optimized parameters for cover panel forming process were obtained through FE simulation.To sum up, the results presented in the paper are valuable for practice of cover panel forming process. Incorporating reverse engineering method into FE simulation of automobile cover panel forming process is conducive to employ information technology in auto-industry and has important scientific and practical significance.