Batch construction heuristics and storage assignment strategies for walk/ride and pick systems

The retrieval of items from storage is a chore faced by virtually every bus iness concern. Walk/ride and pick systems are a popular method for performi ng this chore in many applications. When retrieval requests consist of mult iple items, order pickers must travel to numerous storage locations to comp lete each order. When these requests are made in sufficient volume, a metho d of order retrieval known as batch picking is often used. Batch picking is a popular approach in the mail-order industry and is employed in industria l settings such as tool cribs and in warehouses, which service assembly lin e operations. Batch construction heuristics are developed and tested under three strategi es for assigning storage space to individual items that have been suggested in the literature. Our results are derived from the simulation of a single hypothetical warehouse model. Specifically, we employ a model that is squa re in travel distance and assume the walk and pick method of order retrieva l with sequential one-way travel. Sensitivity analysis is performed on work force level and batch size. Our results indicate that the methods used for constructing batches of orders and for assigning storage space to individua l items can significantly impact order retrieval efforts in warehouses of t his type.