A stochastic model of empty-vehicle travel time and load request service time in light-traffic material handling systems

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.

Notes

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