Based On Petri Net For Mixed Model Ssembly Lines Scheduling Roblem Reseach

With the development of the society and the advance of the scientific technology,the modern manufacturing enterprises are facing a series of problems, such asunpredictable and fast market competition that is strengthening changeably andconstantly.Just under this kind of background,mixed model assembly lines(MMAL)becomes one of the most competitive and potential manufacturing pattern.The mixedmodel assembly lines is a new manufacturing system,which is designed at the outset ofrapid change in structure in response to multi-type,varied-toting,multi-function,quickdelivery,and sudden changes in market.As an advanced manufacturing system,MMALhas become the research focal point of assembly field in recent years.The paper wassupported by the ministry of education humanities and social science research projectfund"Based on the random control with mixed model assembly process optimizationalgorithm for research"to research the mixed model assembly lines system modelingand scheduling problem solving.On the basis of theory of discrete event systems,computation intelligence and computer technology, the theoretical and practicalaspects of the three issues are studied.The main research contents of the paper are outlined as follows:1. The current research situations of the assembly systems are reviewed andanalyzed,the generic research methods and existed problems are pointed out.2. the modeling technology of MMAL is studied.Considering the characteristicsof complexity,reconstructing,intelligent and autonomy of the MMAL,an agent orientedknowledge colored timed Petri net(KATCPN)modeling approach is proposed.Based onthe classification of resources,the resource agent is encapsulated so that knowledgecolored timed Petri net base resource agent is built.The KATCPN model of mixedmodel assembly cell is composed of different resources agent by transition.Accordingto the logical relation of each mixed model assembly cell,the transitive relation ofmessage for assembly system is determined and the assembly line could be quicklyconfigured using this method.finally.Finally, examples demonstrate the feasibility ofthe model.3. The mixed model assembly line scheduling problem isstudied.Using theToyota company put forward to the rate of parts of evenly as the scheduling goal,put forward the mixed model assembly line of the optimizationscheduling mathematicalmodel.At the same time,put forward an add heuristic rules of the constraints of geneticalgorithm as mixed model assembly line scheduling problem solving method,thealgorithm of genetic operations in the use of dynamic mutation rate adaptivestrategies,and to ensure the groups of diversity,to avoid the prematurity of thealgorithm convergence,to improve the algorithm global optimization ability.Case studyproved that the improved genetic algorithm is feasible and effective.