The Effect of Storage and Routing Policies on Picker Blocking in a Real-life Narrow-aisle Warehouse

Abstract

Upcoming e-commerce markets force warehouses to handle a large number of orders within short time windows. Narrow-aisle order picking systems allow to store a large number of products in small areas. In manual order picking systems, narrow aisles can result in substantial waiting time compared to wide-aisle systems. The objective of this study is to analyse the joint effect of the two main operational order picking planning problems, storage location assignment and order picker routing, on order picking time, including travel time and waiting time due to picker blocking. Multiple horizontal and vertical storage assignment policies, as well as multiple routing policies are simulated with the aim of reducing order picking time. The results of a full factorial ANOVA are used to formulate managerial guidelines to increase order picking efficiency in narrow-aisle systems in order to face the new e-commerce market developments resulting in enhanced customer service.