Template-Type: ReDIF-Paper 1.0
Author-Name: Yu, Y.
Author-Name-Last: Yu
Author-Name-First: Yugang
Author-Name: de Koster, M.B.M.
Author-Name-Last: de Koster
Author-Name-First: René
Title: Optimal Zone Boundaries for Two-class-based Compact 3D AS/RS
Abstract: Compact, multi-deep (3D), Automated Storage and Retrieval Systems (AS/RS) are becoming more common, due to new technologies, lower investment costs, time efficiency and compact size. Decision-making research on these systems is still in its infancy. We study a particular compact system with rotating conveyors for the depth movement and a Storage/Retrieval (S/R) machine for the horizontal and vertical movement of unit loads. We determine the optimal storage zone boundaries for such systems with two product classes: high and low turnover, by minimizing the expected Storage/Retrieval (S/R) machine travel time. We propose a mixed-integer nonlinear programming model to determine the zone boundaries. A decomposition algorithm and a one dimensional search scheme are developed to solve the model. The algorithm is complex, but the results are appealing since most of them are in closed-form and easy to apply to optimally layout the 3D AS/RS rack. The results are compared with those under random storage, and show that a significant reduction of the machine travel time can be obtained. Finally, a practical example is studied to demonstrate the use and validate our findings.
Creation-Date: 2007-05-10
File-URL: https://repub.eur.nl/pub/10180/ERS-2007-034-LIS.pdf
File-Format: application/pdf
Series: RePEc:ems:eureri
Number: ERS-2007-034-LIS
Classification-JEL: M, M11, R4
Keywords: AS/RS, Class-based storage, Order picking, Storage rack design, Travel time model
Handle: RePEc:ems:eureri:10180