Sequencing in Flexible Assembly Systems with Blocking

柔性制造系统中的一种重要生产线配置是由多个串联的装配站组成的。通常，每种产品类型都以相同的顺序流经这些站点。然而，每种类型可能具有不同的处理时间。一些先进的生产线有能力跳过工位，当作业不需要在它们那里处理时。此外，如果前一个作业仍在处理，则可以阻止在机器上处理该作业。这通常被称为“阻塞”，是当代准时化制造战略最感兴趣的主题。如果在阻塞上花费太多时间，总线路吞吐量将严重下降。缓解阻塞的旧方法一直是在组装工位之间放置缓冲区，以吸收处理时间的差异。然而，现代制造方法高度重视减少在制品库存。因此，找到加工不同产品类型的最佳顺序对于最大化生产线吞吐量至关重要。

An important production line configuration used in flexible manufacturing systems consists of several assembly stations in series. Usually, each product type flows through these stations in the same order. Each type, however, may have different processing times. Some advanced lines have the ability to skip stations when the jobs require no processing at them. Also, a job can be kept from being processed on a machine if the preceding job is still being worked upon. This is commonly known as "blocking" and is a subject of prime interest for contemporary, just-in-time manufacturing strategies. If too much time is spent in blocking, total line throughput will be severely degraded. The old approach to ease blocking has been to place buffers between assembly stations to absorb differences in processing times. However, modern manufacturing methods place high priority on reducing work-in process inventory. Thus, finding an optimal order in which to process the different product types becomes critical for maximizing line throughput.