A fixture design system for networked manufacturing

摘要

Fixture design is a complex and intuitive process. An efficient fixture design system is essential to cut costs and reduce product lead time. For networked manufacturing, the fixture design system must contain characteristics of rapid configuration designing, three-dimensional (3D) modelling, a completely standardized elements database, and it should be able to transfer information with various other systems. For the requirement of rapid configuration design, based on the analysis of the contents and characteristics of fixture design, a hybrid CBR/KBR (case-based reasoning/ knowledge-based reasoning) fixture design method is proposed, with CBR as its core, KBR as its assistant and CBR as the support of case-adaptation process. Using design information, the designer can obtain a satisfactory subset of possible configuration designs of a fixture from the KBR process. Then the designer, using this subset and other information (via FIXCOD system), can obtain a similar design of the fixture from the retrieving case database, and then finally use the CBR adaptation technique to obtain the satisfied design of fixture. Networked information releasing technology is applied to part design in the computer aided design (CAD) system, and a new 3D modelling method is presented, driven by networked parameters. The data on the web are integrated into the CAD system to realize multithreading data exchange between the web information releasing system and the CAD system, which will make the CAD system obtain data from the web. Then networked 3D modelling will be realized by the driving of parameters from the web, and a proved model based on CATIA is provided. The internet and the use of extensible mark-up language (XML) as a file format provide a means for the transfer of information and knowledge between the various computer aided manufacturing (CAM) systems. The system has been implemented using Java and is based on a three-tier browser/server (B/S) architecture. This ensures the platform independent performance of the system.