Operations sequencing in automated warehousing systems

The block sequencing strategy, where retrievals are sequenced and executed in blocks, is commonly assumed in many works on operations management in automated warehousing systems. The nearest neighbour heuristic is a popular sequencing method. In this work, the destructive effects of block sequencing on the system’s performance: waiting times and queue length, in a non-deterministic environment, is demonstrated. Dynamic application of the nearest neighbour as a dispatching rule is proposed as an alternative. The performance level of the dispatching nearest neighbour rule is surprisingly high.