Study On Virtual Cellular Dynamic Formation And Scheduling With New Task Insertion

Facing the increasing of market competition, personalized customer demand, complicated production environment and so on, the enterprises need to introduce advanced manufacturing mode and efficient production technology to improve their production ability, market response ability and comprehensive competition ability. As a kind of innovative production mode which gives consideration to both flexible production and effective production, Virtual Cellular Manufacturing System(VCMS)integrates agile manufacturing and lean production, takes task-oriented and process-oriented to optimization grouping, and makes logic dynamic reconfiguration in order to timely coordinate the shared resources, ensure logistics load balancing and then optimize the whole process of dynamic scheduling, which can overcome the limitations of the traditional cell production, make rapid response to the changing market, and gradually become a effective way of realizing many varieties and small batch production mode.In the actual production process, some random events often occur which disturb the production order and may not make the original production plan to be properly implemented. To this end, on the basis of analyzing relevant theories and research status of relevant theories and research status, this paper specifically researches the dynamic formation and the dynamic scheduling of virtual cellular manufacturing system with new task insertion. First of all, in the case of the existing virtual cell with new task insertion, a new similarity coefficient formula combining new task and the existing virtual cell is proposed, which comprehensive measures the similarity between the new task and the product family and equipment group of the existing virtual cell. And then, according to the similarity criteria, virtual cell is reformatted, which can make new task and the original tasks to be normal produced.With the mechanism of sharing resources, within a certain period of time, the production tasks at the same time, may need to use a shared resource in one virtual cell or among the virtual cells. Within the specified period, under the established number and the ability of resources, if resources cannot satisfy the production, the resource conflict is existed. After a new task inserts, the reformed virtual cell made by the new similarity coefficient method may exist the resource conflict phenomenon. Therefore, Bayesian network method is used to identify the resource conflict, and with the critical chain method, using the cell priority and operation priority is to resolute the resource conflict, which can ensure that the tasks are done smoothly, the system is stable and realize the dynamic scheduling of the virtual cell.In order to verify the effectiveness of the dynamic formation and dynamic scheduling methods, this paper focus on HDZH shipbuilding(group) co., LTD. and analyzes the related issues of its present production management. At the same time, combining the new task that often appear in actual production process, this paper applies the proposed method of the virtual cellular dynamic formation and dynamic scheduling to the company’s pipe processing workshops. The optimization result satisfies the flexible production and dynamic requirement, which further shows the feasibility and effectiveness of the proposed method.