Physical Model-based Data Management System

Influenced by the economic globalization, China is becoming one of the world's "Manufacturing plants" at a faster pace since the very beginning of this century. In order to survive in the drastic competition for the market, most manufactories have to shorten their product developing cycle on the premise of ensuring the quality of the products. However, the product designing methods and modeling in existence have some deficiencies, such as, 1. They can only describe geometric information, and the designing process is infected by many non-geometrical factors; 2. They ignore the utilization of designing experience which is gained during product designing process. For most of the enterprises, a very realistic problem is how to dig out from the present resources valuable experience that is useful for designing. After studying the present state of both domestic and foreign modeling theories, we propose the concept of PM (Physical Model), which, combining the geometric model, the topological model, and especially the assembly model of the present CAD system, can describe and record the geometrical, topological, and assembly information of mechanical parts, the load of product and other physical and mechanical information. Carrying out rationalized designing on the basis of PM is a breakthrough to the product designing theory. This paper intends to build a data management system based on the PM. By effectively organizing the related design information during the rationalized designing process, the data could be shared, and, especially, the designing experience could be utilized. This research is made on the Pro/Engineer platform. Through the development of this system and its application to engineering examples, it can be proved that the data management system for rationalized designing which is based on the PM could conduce to the realization of integrating and sharing of design data, shortening product developing cycle, and improving the enterprises' competing ability.This paper is developed in 6 chapters and introduces at length the data management model, the system structure, the capture and the organization of data, which are all included in the data management system for rationalized designing basedon the PM, and also introduces through engineering example the utilization of design information. The 1st chapter presents the background in which the theme is put forward, analyzes the deficiencies of the designing theories and ideas in existence, points out their limitations in integrating and utilizing information, determines the aim of the rationalized designing idea, indicates the key problem to be studied in the theme, i.e., experience utilization, and arranges the work for the whole paper. The 2nd chapter briefly summarizes the development of product modeling ideas, confirms the idea of top-down designing in pursuit of precision gradually. The 3rd chapter introduces the PM, including the definition, the system structure, the data structure, and the main function modules, and then indicates the necessity of rationalized designing based on the PM. The 4th chapter deals with the experience management model of rationalized designing, and further gives the designing data management model in a broader sense; it also introduces a version management method for design information, which lays a foundation for the implementation of the data management system based on PM. The 5th chapter introduces the implementation of the data management system in detail. First, it introduces the system structure of the data management system based on PM, and then particularly discusses information capture and organization. Through an engineering example - the reducer designing process, the 6th chapter demonstrates how the system captures, organizes, and utilizes the design information, and further validates the feasibility of the research. Finally, the paper makes a summarization to the theme and gives an expectation.