The Research Of CAD Modeling And Redesign Technology In Reverse Engineering

As one of the most important methods of modern advanced design, the reverse engineering (RE) is playing an increasingly important role. With the development of computer graphics, computer aided geometric design, high performance computing and other relative technologies, RE has being deeply researched and widely used. In order to RE is conducive to innovation redesign of product, how to combine with the reverse design and forward design becomes one of the focus problems of RE research. This thesis mainly studied the method of RE modeling for redesign, and it wanted to provide the practical advice for RE application.According to the different processing ways to different products, the main content of this paper contains:reverse modeling in the products of structural type and method of redesign, reverse modeling in the surface products and method of redesign based on surface deformation. The commercial software of CATIA and ThinkDesign as the platform was used in this paper, to study the relevant technology of reverse modeling and method of redesign based on RE theoretical.When facing the problem of structural products reverse modeling, this paper proposed some methods of extraction for kinds of character according to the existing, mature commercial CAD software and relevant theoretical about character extraction. For example:extraction of auxiliary feature, extraction of sectional feature, extraction of 3D curves and so on. Through this extraction, we can not only exactly reflect the design intent of original products, but also get a parameterized feature model. So this is benefit to support innovation redesign.When facing the surface products, this paper also proposed the method of surface reverse modeling based on features. That is fitting and extraction of freeform curves and surfaces, extraction of multi-sectional feature, extraction of blend surface and so on. So it can get a CAD model fit to the original design intent, and at the same time the quality of the surface can be guaranteed. Moreover, this paper studied the method of redesign based on surface deformation. For example, deformation based on constraint, deformation based on control points and so on. Through that there is an approach to redesign for that non-parametric surface CAD model as the structural CAD model.Through an example in this paper, those methods were proved to be an effective path to products innovation redesign.