Research On System Of Manufacturability Analysis Of Mechanical Parts

Based the study in the manufacturability evaluation methods of machine's parts, combine with the requirement of the project "The system of developing hi-tech product for area economic development", which is sponsored by the Committee of National Development & Plan, a knowledge-based system for analyzing the manufacturability of machine's parts was founded in this paper. The rotational parts were used as examples in the system.First, this paper compared the concepts of "manufacturability evaluation" and "manufacturability analysis", then gave the conclusion that manufacturability analysis system was the base of instantaneous DFM design system in future. There are two key points from the current manufacturability analysis system to instantaneous DFM design system. One is the integration of manufacturability analysis system and CAD system, the other is the reasoning of manufacturability analysis system is fast enough. This dissertation give a system based Pro/Engineer, it also put forward some new methods concerned on knowledge representation, feature-based part modeling and reasoning mechanism.Knowledge acquisition and knowledge representation is the key technology of DFM system. An integrated knowledge representation method which can represent parts manufacturability knowledge is developed after studying the composing, the classification, and the characteristics of parts manufacturability knowledge. Based rotational parts and Microsoft ACCESS, the knowledge is set up, and the knowledge base is organized for improve the efficiency of reasoning engine. After studying parts manufacturability knowledge and parts themselves, summed up rotational parts' feathers and their parameters, advanced all kinds of information that the part's molding should be included, then gave the structure of the part's molding.The reasoning engine is designed with mixed reasoning direction, it uses part's feature-based molding tree as its facts. The reasoning engine can obtain the information from molding tree to avoid to input much of data or to answer many questions, so the operation of the system becomes simplified. Through assorting and filtering knowledge bases by sort keywords and matching rules step-by-step, the reasoning engine is high efficient.In the beginning, the dissertation studies some relational advanced design theories and several evaluation methods of product manufacturability, then decides the functions and the essential technology of IDFM. In the end of the dissertation, a conclusion is educed and next research is pointed out.