Study On Virtual Cellular Dynamic Formation Problem By Double Driven Of Period And Event

With the product life cycle continuously shortening, increasing product variety and thegradual improvement of market personalized requirements to make the manufactutingenterprises facing the grim situation. In the dynamic changeable environment, how toquickly response changing market demand has become a key to make the enterprise in animpregnable position. Virtual cellular manufacturing system is an innovative way ofproduction organization which both in the production of flexibility and efficient. And itgradually becomes an effective mode to realize many varieties and small batch production.Cell formation is the first step to implement cell, and plays a decisive role in response tocustomer demand timely.In the changeable market environment, the internal configurationof cell also need subsequently adjust. In response to the changing demand of product mixesand components, virtual manufacturing cell can be according to the requirements ofdifferent products, when the task is accumulated to a certain number then periodically createvirtual cells, namely at some stage of cell formation may not be suitable for the next stage,so it is necessary to reconfigure cellu at any time. However at the same time there are slaodiaturbance in the manufacturing system, such as order changes. When there is a new order,the original parts are usually configured on the processing manufacturing resources. Underthe premise of not disturbing the original tasks to make the new order to be processed assoon as possible is also a problem to be solved.Based on the discrete manufacturing enterprises to implement virtual cellular productionmode is as the research background. In the research status of virtual unit mode of production,especially after carried on the thorough analysis of cell formation problems, this paperstudies the cell formation dynamicly problems.Multi-periods dynamic formation problem is studied that virtual cellular internalconfiguration can be adjusted dynamically in the dynamic changeable situation of marketdemand, and the corresponding system reconfiguration planning model is established. Inmodel design, the model incorporates parameters of the problems of product dynamicdemand, machine capacity, operation sequence, balanced workload, alternative routings andbatch setting. The objective of mixed integer programming model is to minimize the totalcosts of operation, moving raw materials, inventory holding and process routes setup.Fordiscrete manufactures in the production process often appear changes of order, this paper studies virtual cellular dynamically formation problem under the condition of new ordersincrease, and set up multi-objective mathematical programming model to maximize the sumof parts processing route similarity coefficient and equipment load balance, minimize thetotal costs of operation and put forward the improvement of cooperative multi-objectiveoptimization algorithm to join the cataclysm operator to solve the mathematicalprogramming model. Through the similarity criteria of the new parts with the existingvirtual cell, to make new jobs to be processed as soon as possible, at the same time themanufacturing resources were made optimized.In order to verify the application of virtual cellular production mode in discretemanufactures. This paper combines with the actual situation of a shipbuilding enterprise toillustrate the dynamic cell formation problem in thevirtual cellular manufacturing system.Proposed the corresponding plan for virtual cell formation, this paper made a comparisonbetween the result before and after improvement. The results showed the feasibility andeffectiveness of the proposed program.