Order Batching in a Bucket Brigades Order Picking System with Consideration of Picker Blocking

A bucket brigade strategy allows workloads in warehouses to be distributed with a minimal level of managerial planning and oversight. However, the variability and uncertainty of the pick locations within a particular order or batch often results in picker blocking and subsequent losses in productivity. This study formulates an order batching model for robust blocking control of dynamic bucket brigade OPSs. The Indexed Batching Model for Bucket brigades (IBMB) is composed of indexed batching constraints, bucket brigade picker blocking constraints, and release-time updating constraints. We show that the model minimizes the total retrieval time and improves picker utilization as much as ten percent across diverse and practical order picking situations.