Abstract
Empty-vehicle travel time plays an important role in the design and control of automated guided vehicle systems (AGVSs). However, many analytical models of these systems assume the amount of empty-vehicle travel time is the same as the loaded-vehicle travel time. This paper examines empty-vehicle travel time in AGVSs with low traffic intensity. The model uses a discrete-time Markov chain based on vehicle location and represents dispatching rules in the one-step transition matrix. The model can be used to compute moments and cumulative probabilities for the empty-vehicle travel time. Coupled with the loaded-vehicle travel time and the loading/unloading time, similar results can be obtained for the time to service a load request.
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References
Hodgson, T., King, R. and Monteith, S. (1987) Develo** con-trol rules for an AGVS using Markov decision processes. Material Flow, 4(1), 85–96.
Schwind, G. (1990) AGVS: latest developments in guidance sys-tems. Material Handling Engineering, November: 53-60 (1990).
Egbelu, P. and Tanchoco, J. (1984) Characterization of automatic guided vehicle dispatching rules, International Journal of Produc-tion Research, 22(3), 359–374.
Malmborg, C. (1990) A model for the design of zone control automated guided vehicle systems. International Journal of Pro-duction Research, 28(10), 1741–1758.
Egbelu, P. (1987) The use of non-simulation approaches to esti-mating vehicle requirements in an automated guided vehicle based transport system. Material Flow. 4(1-2), 33–51.
Kaspi, M. and Tanchoco, J. (1990) Optimal flow path design of uni-directional AGV Systems. International Journal of Production Research, 28(6), 1023–1030.
Malmborg, C. and Shen, Y.-C. (1994) Heuristic dispatching models for multi-vehicle materials handling systems. Applied Mathematical Modelling, 18, 124–133.
Shen, Y.-C. (1995) The impact of vehicle dispatching on the design of multiple-transporters material handling systems. Ph.D. dissertation, Virginia Polytechnic Institute and State University, Blacksburg, VA.
Shen, Y.-C. and Kobza, J.E. (1997) A dispatching-rule based al-gorithm for automated guided vehicle systems design. Production Planning and Control, (to appear).
Srinivasan, M., Bozer, Y. and Cho, M. (1994) Trip-based material handling systems: throughput capacity analysis. IIE Transactions, 26(1), 70–89.
Ross, S. (1993) Introduction to Probability Models, Academic Press, Inc, San Diego, CA.
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Kobza, J.E., Shen, YC. & Reasor, R.J. A stochastic model of empty-vehicle travel time and load request service time in light-traffic material handling systems. IIE Transactions 30, 133–142 (1998). https://doi.org/10.1023/A:1007410016136
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DOI: https://doi.org/10.1023/A:1007410016136