An optimum-seeking approach to the design of automated storage/retrieval systems

This paper reports on an optimum-seeking approach to the design of automated storage/retrieval systems. The method was developed to improve the effectiveness with which simulation models of such systems can be used as design aids. The system modeled consists of several aisles of storage bins, storage retrieval devices (stacker cranes), closed loop conveyor, work stations, and input/output buffers to interface with the conveyor. Since simulation models are only descriptive in nature, there is no algorithmic way proceed toward an optimum design specification. Starting with an expected value or balanced flow model, however, the simulation can be used to develop a cost effective design. An interactive program assists the designer in developing the expected value model. From this point, optimum-seeking rules or heuristics are used in conjunction with the simulation model to reach a local optimum solution. Several rules are proposed and evaluated.