A new technology for unit-load automated storage system: Autonomous vehicle storage and retrieval system

Material handling is a growing, $80 billion industry that is central to the nation's economic competitiveness and national defense. A major segment of this industry is unit load (UL) storage and retrieval (S/R) systems which form a critical link in global supply chains. The first step in UL S/R system design is the configuration from which subsequent design details are derived. Most UL S/R system life cycle costs and capabilities are established during the selection of S/R device technology, UL throughput rates, storage capacity and system configuration. The crane-based automation technologies were introduced in the 1970s. Automated storage and retrieval system (AS/RS) has been widely used in distribution and production environments to store and retrieve loads (Roodbergen KJ, Vis IFA (2009) A survey of literature on automated storage and retrieval systems. Eur J Oper Res 194:343-362). An AS/RS usually consists of conveyors, racks and automated S/R devices (cranes). The cranes are fully automated and can travel in aisles between the racks to pick up and drop off loads. Between 1994 and 2004, there has been a significant increase in the number of AS/RSs used in distribution environments in the United States (Roodbergen KJ, Vis IFA (2009) A survey of literature on automated storage and retrieval systems. Eur J Oper Res 194:343-362). The most important advantages of using AS/RSs over non-automated systems are: savings in labour costs and floor space, increased reliability and reduced error rates. However, it has significant disadvantages including the high investment cost, less flexibility and higher investments in control systems (Zollinger H (1999) AS/RS application, benefits and justification in comparison to other storage methods: a white paper automated storage retrieval systems. Production Section of the Material Handling Industry of America). © 2012 Springer-Verlag London Limited