Research And Development Of Intelligent Design System For Welded Jigging Machine Based On Case

Automobile welding fixture is very important process equipment to guarantee thewelding quality and accuracy of body. With the maturity of CAD technology and the rapiddevelopment of knowledge engineering, the flexible degree of fixture is more and morehigh. Construction of intelligent system of automobile welding fixture basedon case-based reasoning can reduce the cost, shorten the cycle and promote the upgradeof the automobile, which is an indispensable element in the field of artificial intelligenceand has become one of the hot research at home and abroad. The method of case-basedreasoning is adopted, the knowledge database of automobile welding fixture is constructed,the modular architecture of the intelligent system is analyzed and the workflow ofintelligent design system of automobile welding fixture based on case-based reasoning ispresented in this paper.On the construction of knowledge database of automobile welding fixture, thebackground and status at home and abroad is analyzed. The case database，moduledatabase and part database is constructed from the view of universality, flexibility andportability， which is parameterization and standardization. The rule database isconstructed according to design specifications and requirements，which is used to selectcylinder. Based on the object-oriented method and group technology, The knowledgeexpression and package management for the information of knowledge database is takenin this paper.On the realization of intelligent design system for automobile welding fixture, Thedifferent structure of automobile welding fixture is studied systematically, the differentfactors of case unit structure are analyzed, the hierarchical relation is presented, judgmentmatrix is constructed and weight coefficients are calculated in this paper. The analyticalhierarchy process is applied in automobile welding fixture and a brief introduction to theK-Nearest Neighbors is given in the paper. The distance function is defined to solve thesimilarity and expand the search scope in this paper.In the design process based on case-based reasioning, The modularization principle is adopted to divide the whole system into four sub modules in this paper, which comprisespath configuration module, information management module, case management moduleand reasioning design module. Case-based reasoning is relatively mature, which cansimulate human thinking and realize the retrieval, reuse, revise and storage of the case.Rule reasoning is embeded in the process of matching in this paper, which saves the timeof selecting component, improves the design precision and reduces duplication of thelabor.The research of intelligent design system for automobile welding fixture is carried onthe NX8Platform, which combines with the VC++6.0programming software.Information is extracted from assignment book and input system for retrieval.3D modelsof case database are imported into the NX platform, which successfully realizes theinteractive intelligent design. The working flow of intelligent design system is discussedin this paper through the experimental verification and achieves the design of simplefixture unit. The research of intelligent design system for automobile welding fixtureachieves perfect combination of MFC dynamic link library and the NX/OPEN APIfunction, which has important theoretical and practical significance.