A hybrid model for the control and the analysis of complex 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. This area is usually modeled as a discrete event system, while the overall system performance depends also on continuous time phenomena. A hybrid 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.