A discrete event model for the control and analysis of complex automated warehouse systems

In the last twenty years, a big effort has been made to find optimal strategies for planning and control of automated warehouse systems. An automated warehouse system has two main components: an automated storage and retrieval subsystem consisting of a number of aisles, each one served by a crane, and a picking area which is formed by bays where stock units coming from the aisles are partially emptied by human operators. These two components are connected via an interface area consisting of carousels, conveyors and buffers. The role of this interface area is usually neglected, while the overall system performance depends on how this subsystem is controlled. A model focusing on the interface area is proposed in this paper to improve the control and the analysis of complex automated warehouse systems. A real case study is considered to show the effectiveness of the approach.