A Polynomial Time Tour Algorithm for Order Picking Operations in Warehouses and New Aisle Designs

Abstract

In this paper we aim to develop a new innovative warehouse design that provides savings for order picking operation which is the most costly and the most related operations with the order delivery time in warehouses. For this purpose we propose a Discrete Cross Aisle Warehouse Design layout as an alternative to traditional 2-block warehouse layout. In this proposed layout linear middle cross aisle is designed as a discrete structure (one tunnel on each pick aisle). Harmony search algorithm is used to find an optimal tunnel positions that minimize the average tour length under randomized storage policy by searching the space of all possible designs. In order to calculate average tour length on a proposed design an algorithm that solves order picking problem optimally in polynomial time is presented. Computational experiments show that optimum designs have the same layout with the traditional 2-block design for small size order lists. As the number of locations to be visited increases we propose new tunnel allocations that present up to 5% less travel than that in 2-block traditional layout. Warehouse design order picking tour algorithm and randomized storage. © 2017 Elsevier B.V. All rights reserved.