基于滚动窗口技术和遗传算法的柔性作业车间动态调度研究

Dynamic scheduling of flexible job shop based on rolling window technology and genetic algorithm

在柔性车间的动态调度过程中,存在生产效率和设备利用率低的问题,为此,提出了一种基于滚动窗口技术和遗传算法的柔性车间动态调度新方法。首先,采用最大完工时间最小作为评价指标,根据滚动窗口技术的特点,对滚动窗口中参数的修正、重调度时刻的解码以及窗口中工件的数量和调度周期进行了分析,为后续研究提供了理论指导;然后,采用分段编码的方式对机器选择部分和工序排序部分进行了编码,并设计了相应的交叉操作、选择操作方法;最后,采用工件和机床数据对柔性车间动态调度新方法进行了实验验证。研究结果表明:采用基于滚动窗口技术与遗传算法的新方法求得的最短完工时间值为17,在保证了遗传算法具有全局搜索性能的基础上,既能满足用户多品种、中小批量生产的要求,又能有效降低生产成本;在有效处理动态事件的前提下,该方法既能提高作业车间的生产效率,又能保证设备具有较高的利用率,满足柔性作业车间的动态调度要求。

Aiming at the problem of low production efficiency and equipment utilization in the process of flexible workshop dynamic scheduling,a new flexible workshop dynamic scheduling method combining rolling window technology and genetic algorithm was proposed.Firstly,the minimum completion time was used as the evaluation index.According to the characteristics of rolling window technology,the correction of parameters in rolling window,the decoding of rescheduling time,the number of workpieces in window and scheduling cycle were analyzed,which provided theoretical guidance for subsequent research.Then,the machine selection part and process sequencing part were coded by segment coding,the corresponding crossover and selection operation plans were designed.Finally,the solution method of flexible workshop dynamic scheduling problem was verified by workpiece and machine tool data.The results show that the shortest completion time obtained by the combination of rolling window technology and genetic algorithm is 17,which ensures the global search performance of genetic algorithm,and can not only meet the requirements of users with multiple varieties and small and medium batches,but also effectively reduce their own production cost.On the premise of effectively dealing with dynamic events,it can not only improve the production efficiency of the job shop,but also ensure the equipment utilization,which meets the requirements of dynamic scheduling of flexible job shop.