任务工时不确定的模具车间前摄性调度研究

摘要

由于模具生产属于非重复性生产模式,各工序的工时具有很强的随机不确定性,这给模具车间制定合理可行的作业计划带来了一定的困难。针对这一实际问题,提出了一种考虑任务工时不确定性的前摄性车间调度算法。首先,分析了模具精加工环节的两道关键工序对制造系统稳定性的影响,并基于工序的工时不确定特性,建立了任务工时不确定的离散概率模型;然后,以调度方案的稳定度作为优化目标,构建了两阶段流水车间前摄性调度模型,针对该模型,提出了一种变宽集束搜索求解算法;最后,将该算法与定宽集束搜索算法进行对比分析,结果表明该算法能很好地兼顾求解质量和计算时间。%Due to non-repetitive manufacturing of mould die industry,the processing time of operations is random uncertainty.Hence,it is difficult to make a reasonable and feasible baseline schedule in the mould shop floor.To deal with this problem,a proactive scheduling algorithm with uncertain processing times was proposed herein.Firstly,how did two critical operations in the mould finishing stage to impact the stability of whole manufacturing system was analyzed.Based on the characteristics of uncertainty of processing time quota,a discrete probability model of processing time uncertainty was developed.Secondly,a proactive scheduling model of two-stage flow shop was built,whose objective was schedule stability.Furthermore,a width-variable beam search（VBS） algorithm was presented for solving the proactive scheduling model.Finally,the comparative analysis with the fixed width beam search（FBS） was pursued.And,the computational results show that the presented algorithm has a good balance between solution quality and computation time.