Design and optimization of order picking systems: An integrated procedure and two case studies

This paper outlines an integrated order picking system (OPS) design procedure for the optimization of manual picking activities and shows its practical application by means of a software tool in two case studies. The proposed OPS design procedure takes into account the factors typically suggested in literature for the optimization of the picking process, e.g. warehouse layout, item allocation policy, picking strategy and type, and routing. For each factor, the various design options are listed and described, starting again from the available literature. Then, two real cases are presented to show how the proposed approach can be applied in practice by implementing it in an ad hoc software tool designed in Microsoft Excel (TM). The application of the software tool allowed to evaluate the current picking performance of both companies and to test alternative configurations of their order picking process, in the attempt to improve it. In both cases, the framework proved to be effective to redesign the picking process and allowed deriving practical suggestions for the optimization of the process.