Abstract:

In block stacking storage systems, the warehouse management has to decide whether to apply dedicated policy and store only one item in a lane with undisturbed access to it or to apply shared policy and mix different items in a lane. In the former case, the storage space is not utilized at as high level as in the latter one. The radio-shuttle compact storage systems which allow to automatically storage and retrieving items can compromise both criteria. In such systems, a lane is divided into channels and a channel is dedicated to one item. In this way, the possible number of stored items and storage space utilization is increased in contrary to traditional block stacking systems with dedicated policy. However, when the channels are quite long the increased potential of storage space can be utilized on a moderate level. In this paper, the shared policy for radio-shuttle compact storage systems is introduced. First, a MILP model that minimizes the number of relocated items is presented. Then, using simulations two different layouts of the radio-shuttle system are compared. The equations for storage space utilization for the analyzed layouts are presented. The research indicates that the system efficiency is still the compromise between the accessibility to the items and storage space utilization but the space dedicated for storage can be utilized on a very high level.