Research And Development Of The Instance-based Computer-aided Fixture Design System

Fixture is very important equipment in process of machine manufacturing because it can directly affect the quality of products and productivity and cost. It has been the "bottleneck" factor to restraining the development of modern manufacturing technology.Analyzing the requirement of Computer Aided Fixture Design system, system architecture is proposed. The paper is organized and extended by two parts, including Case-based Reasoning and standard parts library. Based on the analysis of the content and the point of the design of the fixture, the author used CBR methods in fixture design.Though the analysis of the fixture comparability, the rational technology about instance is applied for the practice process of fixture design, at the same time the model for the instance of fixture is set up and express, and then established a part classification and coding system. So the reusability of fixture is improved and obtained the best result of searching with the calculating of comparability which supports feature weights adjusting on-line. A design method of standard parts libraryfor fixture based on template part is presented.VC6.0 and Unigraphics18 applying to above-mentioned theory basis have developed a CAFD system. Applying CBR into fixture design, we can directly solve current problems depending on similar problems previously solved. Thus we can avoid duplication of design work, improve the design quality of fixture and shorten the design cycle.