针对含有并行机器组、可进行多品种小批量生产的可重入航空发动机装配车间,其调度问题的研究属于NP难问题。文中首先采用分层有色赋时Petri网进行系统的逻辑分析;然后给出了三种调度规则:①FCFS+;②SPT+CR+返工工件优先加工;③返工工件优先加工+ATC来实现生产调度;最后采用离散事件系统仿真方法,研究了上述3种调度算法对于最小化系统总的拖期时间的性能影响。实验结果表明,第二种调度最能有效的改善系统性能。
The aircraft engine assembly system is a kind of reentrant system that contains parallel machines and can realize as- sembly production for multiple product-types and small batch size.Its scheduling problem is NP-hard.First of all,we use the Layered,Colored and Timed Petri Net (LCTPN)for logical analysis.Then three dispatching rules are proposed for production scheduling,i.e,(1)the improved FCFS;(2)SPT+CR+higher priority for the rework process;(3)higher priority for the rework pro- cess +ATC.Finally,by using the discrete event simulation method,this paper study the performances of the three dispatching rules for minimizing the system's total tardiness.The results of experiments indicate that the second dispatching rule is the most effective for improving the system performance.