A new layout problem for order-picking warehouses

Abstract

Recent studies of warehouse layout designs show that the travel distance for order-picking operations can be reduced by changing the angle of the cross aisles in the traditional warehouse layout. Thus in this study a new design idea is proposed to search for better layouts for order-picking operations than traditional two-block layouts. For this two angled cross aisles are allowed to intersect in the middle of the storage area. A new constructive aisle model is developed so as to evaluate all possible layouts that can be generated in this problem. In order to calculate order picking tour length for a given number of visits one of the best known metaheuristics algorithm called Ant Colony Optimization algorithm is used. Next Differential Evolution algorithm is used to explore the best values of the design variables to minimize average order-picking tour length for a given number of orders. Last it was shown that two-block layouts are superior to the best-found designs with two angled and intersected cross aisles under the considered design assumptions in this study. © 2019 Elsevier B.V. All rights reserved.