Research On Techniques Of CAD/CAM Integration In Collaborative Development Environment

The rapid development of information technology and network technology quickens the course of economy globalization. Web-based distributed manufacturing is the necessary trend of manufacturing technology. Various computer-aided technologies, such as CAD, CAPP, CAM and so on, are essential tools for product development. And the CAD/CAM integration is the key to implement web-based distributed manufacturing effectively. Thus the researches on technology of CAD/CAM integration in collaborative development environment (CDE) have great value both in theory and practice. It can help enterprise to short the product development time, improve the quality of product, reduce the product cost, and improve the quality of the after service so that the competition abilities of the enterprise are enhanced.In this dissertation, the architecture of CAD/CAM integrated system in CDE is proposed firstly according to characteristics and requirements of CAD/CAM integration in CDE, so a foundation is established for the construction of CAD/CAM integrated system supporting collaborative product development. And the key techniques to implement the integration are discussed so that a foundation has been set up for the other parts of the dissertation.Feature technology is the kernel of CAD/CAM integration, and feature is the medium of information transmission in CDE. According to the information requirements of CDE, feature definition, feature classification, feature relationship, feature representation and establishment and management of feature library are all researched systematically in the dissertation. An idea of representing the hierarchy of feature class using O-O knowledge representation method is proposed. Then O-O representation modes of feature classes are designed and feature library is established. In order to support the maintenance and management of feature library, both the transmission of information among subsystems in CDE and the searching of processing plan during process planning, coding strategy of part feature and feature class are researched in the dissertation.Product modeling is the key to implement CAD/CAM integration. Uniform product definition model is the foundation of achieving collaborative development. In the dissertation, feature-based integrated product definition model is put forward, and the establishment and realization of this model are researched. This model not only can provide whole product data for all subsystems inCDE but also support information transmission among subsystems to make convenience for management and operation of product data and ensure real integration of information in CDE.CAPP is the bridge of connecting CAD, CAM, MIS and other subsystems in CDE. Connotation, function and aim of CAPP in CDE are greater. In the dissertation, a distributed CAPP system based on database and web and integrated computer human interaction is brought forward. Layered process decision-making strategy and process searching mechanism based on part feature code and feature class code are proposed. During the process planning, technologies of process planning navigation and visualization are used. In order to make convenience for collaborative designers to use technical data and knowledge, various methods of representing different kind of technical data and knowledge are studied, a layered technical data and knowledge management model is put forward, and corresponding technical data and knowledge management platform is developed to set up a powerful foundation for process planning.CAD/CAM integrated data management is the base for implementing CAD/CAM integration. In the dissertation, the CAD/CAM integrated database and its datasheets are built applying O-O method. Solutions of information transmission and control during collaborative development and maintenance of consistency are all put out in the dissertation, so as to manage and operate CAD/CAM integrated data effectively, and support distributed multi-users to develop product and related process concurrently.We have developed the C...