A study on Mobil racks automated storage and retrieval system (M-AS/RS)

Our work consists in studying a storage system with Mobil racks (M-AS/RS) which are a variation of the multi aisles AS/RS. This system consists of storage racks moving laterally on rails so that one can open an aisle between any two joint racks, storage/retrieval (S/R) machines, the control system and an input/output (I/O) station. In this paper, our interest was concerned with the mathematical modeling of the average cycle time of the (S/R) machine which is an important criteria of performances for these systems. We developed a continuous analytical expression allowing an approximate calculation of the cycle time of a Mobil -AS/RS. This expression was compared with an existing exact discrete expression.