Research On Feature-based Technology Of Data Exchange Between Heterogeneous CAD Systems

With the acceleration of the process of enterprise information, the more and more intense competition among enterprises, as an important factor affecting the speed of products research, the information exchange of the collaborative products design is directly related to the business benefits. Data exchange technology among heterogeneous CAD systems is an important method to solve this problem. Therefore, a data exchange integration strategy based on feature is built, and research the key technology, details are as follows:(1) By analyzing the feature modeling technology and feature types, the constitution of CAD model's feature information and the description of feature based on basic feature class and extended feature class are given, and determine to use XML to descript and share the CAD model information for the characteristic of the constitution of CAD model's feature information and the advantage of XML.(2) The geometry element identification method based on improved geometry certification is propounded to name and identify the geometry element. A clear identification process is given and the identification method of the sketch element in 2D space, the edges and faces in 3D space is described in detail.(3) The exchange method of sketch constraints, location and topology constraints on the layer of feature are presented for the problem of constraints lost, which resolved the problems about design intent lost and inconsistent with source CAD model of the target CAD model.(4) The frame of the data exchange platform among heterogeneous CAD systems is constructed. Firstly, the operating mechanism of data exchange system is defined by analyzing the operating principle of data exchange tools, then the development of the whole system is completed on UG NX5.0 using VC++6.0, JSP and so on. Finally, the feasibility of the method is proved by two examples and compared with other three methods.Experiments show that this method resolves the problem of exchanging and sharing of CAD model. Compared with other methods, the target CAD model not only reserve the design intent, come along for the source CAD models, but also the target CAD model can be edited and modified.