Study On Virtual Cell Dynamic Coordination Strategy And Dynamic Scheduling Problem

Faced with the market demand of multi-variety and small batch, and the complexproduction environment, the enterprises need to take the advanced manufacturing modeand the effective shop scheduling control technology to improve their competitive ability,production capacity and market responsiveness capacity. Virtual Cellular ManufacturingSystem (VCMS) is an innovative production method which can ensure system flexibilityand efficiency, and also it’s integrated the advanced concepts of agile manufacturing andlean manufacturing. Based on production tasks and production processes, VCMS forms agroup of cells logically, and timely coordinates the sharing of resources, and dynamicreconfiguration to ensure load balancing and optimize the entire scheduling process.Therefore, it can effectively improve the quick responsiveness ability and dynamicadjustment capabilities of the system.Based on analyzing the relevant theories and research status of virtual cell in a deepgoing way, this paper specific studies the dynamic scheduling problem of virtualmanufacturing cell under the combined effect of cycle and events. Considering thecomplexity of dynamic scheduling problem, this paper is divided into two steps. Firstly,considering the plan period control mechanism, this paper adopts the method of timedivision multiple stage to develop the virtual cell production scheduling plan. Virtualmanufacturing cell multi-period dynamic scheduling model was established whichincorporated parameters of the processing task dynamic demand, delivery time, equipmentprocessing capability, and load balance. And we proposed task priority sorting strategies ateach time stage to coordinate the allocation of shared resources. The objective is tominimize completion time and the total materials and components travelling distanceincurred. Meanwhile, the hybrid algorithm combining heuristic rules and ant colonyalgorithm is designed to improve the effect of solution.Considering the complexity and variability of the actual production environment, andon the basis of the cycle scheduling plan, this paper concretely studies virtual cell dynamicscheduling adjustment process with the random events which occurred at a certain time.And we propose dynamic scheduling method with machine breakdown, make decisionaccording to the affected operations and virtual cell available resource capacity, and applythe mixed rescheduling strategy combined with right shift and route change to handlemachine breakdown. These measures can ensure that the processing tasks are successfully completed and the stability of system.In order to verify the validity of the proposed dynamic scheduling model and method,after in-depth research of the HZ ship engineering co., LTD, this paper detailed analyzes theoutstanding problems of its existing production management, and applies the virtual celldynamic scheduling method to the company’s pipe processing workshops, and obtains theoptimization scheduling solution that could satisfy the requirement of flexible production.The analysis of the final result shows that the proposed method is feasible and effective.