This paper considers a parallel aisle warehouse, where order pickers can change aisles at the ends of every aisle and also at a cross aisle halfway along the aisles. An algorithm is presented that can find shortest order picking tours in this type of warehouses. The algorithm is applicable in warehouse situations with up to three aisle changing possibilities. Average tour length is compared for...

Abstract In warehouses, order picking is known to be the most labor-intensive and costly task in which employees account for a large part of warehouse performance. Hence, many approaches exist, that optimize process based on diverse economic criteria. However, these focus single objective at once disregard ergonomic criteria their optimization. Further, influence placement items picked underest...

We propose a simulated annealing algorithm specifically tailored to optimise total retrieval times in a multi-level warehouse under complex pre-batched picking constraints. Experiments on real data from a picker-to-parts order picking process in the warehouse of a European manufacturer show that optimal storage assignments do not necessarily display features presumed in heuristics, such as clus...