关键词: 3维计算机辅助设计, 产品数据管理, 信息集成

Abstract: To deal with problems in three-dimension (3D) Computer Aided Design(CAD), the architecture of Product Data Management (PDM) system oriented to 3D CAD was designed which focused on entity constraints and relationships management.The semantic of constraint and relationship among entities was defined, and the classes of implementing relationship management were introduced. Entity constraint and relationship management supported simultaneous update of related parts within a design. It also helped to ensure consideration of the original design intent or specifications during engineering changes. At the same time, relationship management provided methods for process and knowledge management. Some auxiliary modules in PDM for 3D CAD were discussed. General CAD transform platform provided a viewer for displaying all kinds of 3D model, which were implemented based on ACIS. Attributes and structure information were extracted from 3D model, and function menus such as retrieval attributes were embedded inside CAD systems. Association between 3D model and two-dimension(2D) drawing was maintained in PDM, and the synchronous checking-in and checking-out keep consistency with 3D and 2D. The PDM for 3D CAD has been implemented in several projects.

Key words: three-dimension computer aided design, product data management, information integration