Study On The Key Technology Of Auto-body Panel Forming Process

Auto-body panel is basic constituted part of bodywork, its quality distinctly influences the capability of whole car. As the shape of auto-body panel is very complicated, and auto-body panel requires forming process uniformity of accessory position, the design of forming process is very important.The design of auto-body forming process commonly includes edge un-wrapping, choice of drawing direction, roughcast reckoning, design of addendum, adding the binder surface and setting the draw bead.In this paper, the key technology of auto-body panel forming process is first studied, including the optimizing of drawing direction, sheet unwrapping and the automatic adding of addendum. Then professional and effective modules are created using UG software as a platform for secondary program, using the exploitation tool of UG/Open API, using C programme and using the translating circumstance of VC++. The detailed research performed is as follows:(1) In the aspect of the optimizing the drawing direction, the methods of creating the modules for optimizing the drawing direction of auto-body panels were presented, and basic principles were concluded. According to these principles, three mathematic models, including of the model deciding the possible area of drawing direction, goal function and assessment function of optimizing the drawing direction, were established. Based on the mathematic models, the software module was developed. This module can decide the drawing direction of the panels rapidly and preciously.The typical example is provided.(2) In the aspect of unwrapping the panel sheet, the methods generally usedto estimate the dimensions of the unwrapped sheet were discussed, and the mathematic model for estimating the maximum dimensions of the sheet was established. Based on the mathematic model, the software module for deciding the dimensions of the sheet was developed and testified by the practical examples. To further improve the precision, the maximum solution was modified according to the concept of molding degree.(3) After the drawing direction has been created, the addendum of auto-body panels will be added. At first, the section curves of addendum is analysed, mathematic analytic models are established, the parametric design is finished and method to deal with especial questions is presented.Then the adding process of addendum is overall narrated and three methods of WCS conversion are specified to establish theoretic bases for secondary program.A car back-door is designed by this method as application example to testify the feasibility of this addendum module.With the application of examples, it is feasible to develop professional and effective modules using secondary program technology based on UG software. This will increase quality of auto-body panels die and shorten cycle of making auto-body panels.