Research On Material Delivery Optimization In Mixed Flow Manufacturing Workshop Based On JIT

In order to solve the problems of material delivery in mixed-flow manufacturing workshop,such as untimely delivery,slow response of information and low utilization rate of resources,the optimization of material delivery in mixed-flow manufacturing workshop is studied in the dissertation from two aspects,including the strategy of material delivery and the optimization of delivery routes.Firstly,research on material delivery strategy in mixed-flow manufacturing workshop.Through the analysis of material delivery,the material delivery mode is divided into direct delivery and transit delivery.On this basis,materials are divided into three categories: spare parts,transfer parts and batch parts.By comparing and analyzing various triggering strategies of delivery demand,the automatic triggering strategy of Manufacturing Execution System(MES)with strong feasibility is determined.According to the different types of materials,three dynamic material delivery algorithms based on MES are proposed to determine the trigger point of material delivery,delivery quantity,delivery time window and other information.Secondly,research on delivery route optimization model and algorithm.A multiobjective delivery routing optimization model with time windows and vehicle load constraints is established under the idea of balancing optimizing indicators.Based on the basic particle swarm optimization(PSO),the crossover and mutation operations of genetic algorithm(GA)are introduced to improve the adaptability of the PSO to discrete combinatorial optimization problems.Simulated annealing(SA)is introduced into the renewal of individual extremum of particles,which allows particles to deteriorate to a certain extent and improves the defect of PSO easily falling into local optimum.A Sequence-based grouping combination optimization coding method is proposed to reduce the repetition of particles and improve the efficiency of optimization.And,the results show that the practicability and advantages of the improved algorithm become more and more obvious with the increase of particle complexity.Finally,based on the demand of an enterprise,a prototype of manufacture execution and material delivery system is designed and developed to verify the feasibility and validity of this research.