Determining Number of Zones in a Pick-and-Pack Orderpicking System

In this study we consider a pick-to-pack orderpicking system, in which batches of orders are picked simultaneously from different(work) zones by a group of order pickers. After picking, theorders are transported by a conveyor to the next station for packing. Our aim is to determine the optimal number of zones such that the overall (picking and packing) time to finish a batch isminimized. We solve this problem by optimally assigning items to pick routes in each zone. Weillustrate the method with data taken from a distribution center of one of the largest onlineretailers in the Netherlands