Models for automated storage and retrieval systems: a literature review

Abstract

Automated Storage and Retrieval Systems (AS/RS) are warehousing systems that use mechanised devices to accomplish the repetitive tasks of storing and retrieving parts in racks. Since these systems represent a significant investment and considerable operating costs, their use must be as efficient as possible. AS/RS performance is the result of the interaction of many complex and stochastic subsystems. This reality creates a need for robust and efficient evaluation models. This article complements previous surveys on AS/RS by focusing on the particular research question addressed by each work and the associated assumptions used for the various models designed for evaluating AS/RS. Dynamic models based on simulation dominate the most recent literature; however, static approaches based on travel-time modelling have strongly contributed to the study of AS/RS. This review includes dynamic – simulation-based – models, but considers also steady-state (travel-time-based) models. We believe that this review may be of great help to researchers and industrial users in their search for the best modelling approach for a specific problem.

Keywords:

• AS/RS
• warehousing systems
• warehouse design
• simulation

Acknowledgements

This research was partially financed by grants (OPG 0293307 and OPG 0172633) from the Canadian Natural Sciences and Engineering Research Council (NSERC). This support is gratefully acknowledged. The authors also gratefully acknowledge the insightful comments of two anonymous reviewers.