AGV scheduling for automated material distribution: a case study

We have studied the scheduling of automated guided vehicles (AGVs) for efficient and uniform material distribution from a truck-dock to machining units of the machine shop in an automotive manufacturing plant. The material distribution problem, being a much simpler special case of the more general material transfer problem, is easily amenable to analysis. We have assessed the number of AGVs required to meet the total material requirements of all the machining units in the shop. Proposing innovative dispatch rules, we have evaluated their performance in simulation by monitoring parameters reflecting efficiency and uniformity of material distribution, both for single AGV and multiple AGV case. In multiple AGV case, we introduce the notion of zones having comparable demands for AGV, and assign one AGV to each zone, so that each AGV can operate largely independently--sharing a minimum path with other AGVs using deadlock avoiding protocols. The results of simulation runs and their implications are discussed.