Research On The Approach Of Naming And Identifying Topological Entities In Feature Modeling

As the key technology and the core of manufacturing, the development of CAD has radically changed the research direction of automatic design, greatly improved the quality and efficiency of mechanic design, reduced the period of refreshment of products. A deep revolution of mechanic design is coming. Now 3D technology has bebome the mainstream for its outstanding advantage, which reflects that the application of CAD system tends to be much deeper and wider.Most engineering designs are accomplished through modifying the present designs, so the history-based three-dimensional feature modeling system emerges as the times require. The problem of naming and identifying topological entities is the core problem that the system need to solve. JhSolid system is a history-based three-dimensional feature modeling system. The system has the same problems with the other busyness modeling system in naming and identifying topological entities, can't resolve the problem of rebuilding feature and expressing design intention after engineering modifying.The paper does some research on the naming and identifying topological entities, proposes an approach to naming the topological entities based on face, and gives a research approach to identify topological face and topological edge. The binary tree, multi tree and list are used to record the modeling history and the relationship between the topological entities before and after feature-rebuilding. A researching approach to the topological faces and edges which the feature-rebuilding needs is designed. The system frame is improved or rewrited to make sure that the system frame can give better services for problem resolving.The programs have been proved correct and feasible through coding, debugging and testing and have realized above-mentioned functions successfully.