Research On Fixture Plan Design Based On Case Reasoning

Because of rapid development of market economy, a key concern of a manufacturing company is the ability to design and produce a variety of high quality products in as short time as possible. Quick release of a new product into the market, ahead of any competitors, is a crucial factor in being able to secure a higher percentage of the market place and a higher profit margin. The design time, quality and flexible of fixture have important influence on the development cycle of product and the competitive capability of company. Fixture plan design is the base of fixture design, so it is necessary to study how to determine fixture plan rapidly and effectively. Based on case-based reasoning (CBR), this paper studies on technology for design of fixture plan based on case. The main work is as follows.In this paper, the existing illustrating method for information of parts is studied. Considering the complicated character of box part, multi-levels representation method of part's information, which could express the complicated box part clearly is adapted. XML technology is used to express hierarchy structure and nested relationship of box parts'information effectively. The XML schema definition file and XML expression example of box parts are given. The method of fixture plan design using CBR technology is studied. Because a part needs multiple fixturing in the period of processing, in case expression, the expression method of fixturing sequences and similar elements theory are studied. According to box parts, methods of how to select similar elements, how to determine the priority level of these similar elements and how to calculate the similar coefficient of parts are provided. The most similar case can be found from case base according to the size of similar coefficient. Fixture plan of new problem would be designed based on this one. At last, the rapid prototype system using B/S architecture based on Web network which used for design fixture plan was developed. In the system, ASP technology is applied, and relational database SQL Server 2000 and XML are used as data management, which make the data integrating and sharing between applications.