基于资源顺序的柔性制造系统死锁控制策略

摘要

基于资源顺序提出了一种多项式复杂度的死锁控制策略,保证含有并发执行装配过程的一类柔性制造系统G-system的非阻塞性.首先对系统Petri网模型求取操作库所的资源需求量,在任意一组资源顺序的偏序下,调整操作库所的最大资源需求量,然后对每个资源添加控制保证系统资源不会进入循环等待,从而保证系统不会进入死锁状态.通过实例验证,该策略避免了求取信标,在保证系统活性的基础上明显降低了计算复杂度.%This paper develops a novel deadlock control policy with polynomial complexity based on resource orders that can ensure non-blockingness in FMS (Flexible manufacturing systems) modeled by G-system, which allows concurrent execution of manufacturing assembly processes. First,resource requirement of each operation place can be obtained by computing a Petri net model,and maximal resource requirement of each operation place should be adjusted under any partial order of resources. After that,circuit waiting can be avoided by adding monitors to each resource so that the system would not enter a deadlock state. Finally,an application of the proposed method to a G-system is presented, which indicates that siphon enumeration is avoided and computational complexity is greatly decreased without losing liveness of Petri nets.