Hostname: page-component-78c5997874-fbnjt Total loading time: 0 Render date: 2024-10-31T00:51:42.805Z Has data issue: false hasContentIssue false

PICKING CLUMPY ORDERS ON A CAROUSEL

Published online by Cambridge University Press:  22 January 2004

Yat-wah Wan
Affiliation:
Department of Industrial Engineering and Engineering Management, University of Science and Technology, Clear Water Bay, Hong Kong, E-mail: ieywan@ust.hk
Ronald W. Wolff
Affiliation:
Department of Industrial Engineering and Operations Research, University of California, Berkeley, CA 94720, E-mail: wolff@ieor.berkeley.edu

Abstract

Carousels are rotatable closed-loop storage systems for small items, where items are stored in bins along the loop. An order at a carousel consists of (say) n different items stored there. We analyze two problems: (1) minimizing the total time to fill an order (travel time) and (2) order delays as they arrive, are filled, and depart. We define clumpy orders and the nearest-end-point heuristic (NEPH) for picking them. We determine conditions for NEPH to be optimal for problem (1), and under a weak stochastic assumption, we derive the distribution of travel time. We compare NEPH with the nearest-item heuristic. Under Poisson arrivals and assumptions much weaker than in the literature, we show that problem (2) may be modeled as an M/G/1 queue.

Type
Research Article
Copyright
© 2004 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Bartholdi, J.J., III & Platzman, L.K. (1986). Retrieval strategies for a carousel conveyor. IIE Transactions 18: 166173.Google Scholar
Ha, J.-W. & Hwang, H. (1994). Class-based storage assignment policy in carousel system. Computers and Industrial Engineering 26: 489499.Google Scholar
Karlin, S. & Taylor, H.M. (1981). A second course in stochastic process. New York: Academic Press.
Krouse, D.P. & Schmidt, V. (1996). Light-traffic analysis for queues with spatially distributed arrivals. Mathematics of Operations Research 21: 135157.Google Scholar
Litvak, N. & Adan, I. (2001). The travel time in carousel systems under the nearest item heuristic. Journal of Applied Probability 38: 4554.Google Scholar
Litvak, N., Adan, I.J.B.F., Wessels, J., & Zijm, W.H.M. (2001). Order picking in carousel systems under the nearest item heuristic. Probability in Engineering and Informational Sciences 15: 135164.Google Scholar
Rouwenhorst, B., van den Berg, J.P., van Houtum, G.J., & Zijm, W.H.M. (1996). Performance analysis of a carousel system. In R.J. Graves, M.R. Wilhelm, L.F. McGinnis, D. Medeiros, & R.E. Ward (eds.), Progress in material handling research: 1996. Charlotte, NC: The Material Handling Industry of America, pp. 495511.
Stern, H.I. (1986). Parts location and optimal picking rules for a carousel conveyor automatic storage and retrieval system. In 7th International Conference on Automation in Warehousing, pp. 185193.
Wolff, R.W. (1989). Stochastic modeling and the theory of queues. Englewood Cliffs, NJ: Prentice-Hall.