Tactical and operational models for the management of a warehouse

This paper deals with the modeling, routing, and managing aspects of a warehouse with parallel aisles and cross-aisles, in which we assume a picker-to-part process. Pickers either retrieve in the aisles-stored products to fulfill a customer order, or do some nonurgent activity. The main contribution of this paper is the consideration of constraints, which are often disregarded by other papers. We study in particular the consequences of some 'working conditions' for the pickers on the overall solution quality. We analyze a warehouse layout designated to vehicle routing. We study the organization of products into locations, given some statistical forecasts on the future orders. Then we describe a management strategy to regulate the number of pickers doing the picking activity. Finally, an algorithm is proposed as a solution and tested by simulation experiments.