| The development of Computer-Aid Design (CAD) technology goes through about fifty years' history. It also experiences some important development phase such as two-dimensional drawing, line-frame modeling, and cure-panel modeling, entity-sculpt modeling, character-sculpt modeling and mix-modeling and the action-modeling technology on nowadays. In all these phase it was supported by the technology of parametric interaction and size-driving and variable-driving[1]. From the view of applications, CAD technology has been developed in the phase of CAD/CAPP/CAM based on the Product Data Management (PDM). Therefore extracting the data information from CAD effectively and saving them in the response data structure, then we can erect the tree of product and part product. It act on an important role for providing the reliable data in technical producing to realize integrative production.This paper will aim at different model engineering CAD of every unit of production and the defect of singleness function in existence system, present the algorithm of supporting multi-model extracting information from CAD intelligently, further present constructing the model of CAD/CAPP/CAM integrated system on the basis of PDM technology. In here we mainly discuss the definition of model and the algorithm of data extraction and the data exchange between CAD and PDM, finally discuss the instance about above, then present a model about system integration.At first, a systematic survey of CAD and extracting data from CAD research is given, and then the study objectives of this thesis are presented.Secondly, we introduce algorithm of logical structure and data extraction in generic image document. Then we proposed the new Rectangle-Area-Project algorithm of dividing and presenting in logical structure based on existence GLG(Global-Local-Global) algorithm. Then we introduce the definition of multi-model CAD in the technology of data extraction, including title field and data field and total table. We analyze the relation between content and structure and solve the problems which are the extraction of logical structure and the algorithm of data extraction in free form through the expression of matrix of free form. Base on the data extraction from CAD we discussed the relation between the data exchange about CAD and PDM and technical BOM (Bill-Of-Material).Finally, we validate the operational about the former theory through introducing a application instance, then present the integrated model about CAD and PDM system on basic PDM knowledge, also introduce the model of producing the tree of product in deeply, provide the reliable data guarantee for producing and managing information. In the end we proposed the model of enterprise system integration about CAD/CAM/CAPP.
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