Storage & Retrieval Policies for S/R Machine with Capacity Constraints in Man-On-Board AS/RS

크레인의 능력을 고려한 MOB 자동창고 시스템의 저장과 불출정책

This paper deals with storage and retrieval policies for S/R machine with capacity constraints in Man-On-Board AS/RS. It is assumed that storage sequence is based on SFC(spacefilling curve) routine and that storage layout is dedicated by storage policies. We present several heuristic algorithms for storage and retrieval policies which minimize total distance travelled by the S/R machine. These algorithms are based on COI, group COI, frequency of order, similarity between items and capacity of S/R machine. Experimental results of 24 combinastorial policies are provided to illustrate the performance of the heuristics under various rack utilization ratios. In storage policies, the results show that algorithms considering both similarity and frequency are better than those with COI as rack utilization is increasing. And algorithm using group COI is superior to others. In retrieval policies, the method with revision expression is shown to be better than others.