基于遗传算法和延时Petri网的柔性装配系统的设备调度方法

为解决柔性装配系统的设备调度问题，提出了一种将基于延时Petri网的装配过程仿真与基于遗传算法相结合的调度方法。在该方法中，遗传算法使用的染色体是由延时Petri网模型中的部分选择库所名称排列而成，每个染色体都代表一种设备调度方案。遗传操作包括选择、交叉和变异3种类型，利用基于延时Petri网的装配过程模型进行仿真，得到每个染色体相对应的装配时间，进而将装配时间通过适应度函数转化为适应度。该方法融合了Petri网和遗传算法各自的优点，较好地解决了柔性装配系统中的装配建模和装配任务分配优化的问题。仿真实验证明该方法是有效的。

Facilities assignments of flexible assembly system based on GA & TPN

To solve facilities assignments problem of Flexible Assembly System(FAS),a scheduling method combining Genetic Algorithm(GA) and Time-Delay Petri net(TPN) was proposed.With this method,each chromosome of the GA was coded by some of the selecting places of the TPN model in FAS and represented a kind of facilities assignments plan.The GA included three operations of selection,crossover,and mutation.By simulating the assembly process determined by a chromosome with TPN model,assembly time corresponding to each chromosome was obtained.Adaptability value of the chromosome could be calculated by the assembly time.The method has combined the strongpoint of GA and TPN and resolved the problem of assembly modeling and optimizing facilities assignments of FAS.Finally,the simulations results proved the validity of the method.