Optimization of a Single Machine Flow Rack AS/RS for Minimum Expected Travel Time

In this paper, we aim to determine the optimal dimensions of a flow rack automated storage and retrieval system (AS/RS) using a single machine for storage and retrieval operations. These optimal dimensions are evaluated for minimum expected travel times of the storage and retrieval machine. Enumeration technique is used on a large range of system configurations going from 100 to 20000 storage segments in the rack. Optimization is carried out on six travel time expressions dealing with single and dual cycle travel times. Two dwell point positions are considered. Finally numerical results are studied to investigate the influence of the travel time expressions on the optimal dimensions as well as the shape factor of the system rack.