Fundamental Research On Intelligent Computer Aided Process Planning System

Computer aided process planning (CAPP) system has played a very prominent role in advanced manufacturing system. The intelligent trend is main development trend of CAPP system. This dissertation mainly researched the key techniques of intelligent CAPP. The main contents and achievements of this dissertation as following:(1) Base on the analysis of essential machining features and typical process plans of prismatic box, a fuzzy reasoning model for process selection is put forward. By the model knowledge is expressed as fuzzy membership matrix, it is convenient for use of relation database system and decision of alternative plans.(2) Under the base of studying the typical location plans of prismatic parts, process model and fuzzy comprehensive evaluation model of location datum selection are established. By comprehensive evaluation of pending datums, the system may offer valuable reference information to the technologist.(3) A multi-level decision model for selection of machine, fuzzy reasoning of machine kind and fuzzy comprehensive evaluation of machine spec , is propounded. By divide the decision process into two steps, the decision scope is deflated and the decision complexity is reduced.(4) A combinatorial optimization model for process scheme, based on genetic algorithms, is presented, and the corresponding algorithms are designed. The optimization goal includes best machining qualities, least machine kind and softest process route.(5) A methodology of process sequencing, based on group technology and genetic algorithms, is introduced. This approach makes use of group technology to create typical process route, and makes use of genetic algorithms to improve the route.(6) The information model of CAPP includes feature product model, manufacturing resource model, process plan model and decision knowledge model. Under the base of analyzing the information model, it gave relation database model.