TIGHTENED ANALYTICAL BOUNDS ON THE IMPACT OF DISPATCHING RULES IN AUTOMATED GUIDED VEHICLE SYSTEMS

Rule-specific formulations of the expected volume of empty travel for vehicle recirculation are developed for random and distance-minimizing/maximizing dispatching rules used in automated guided vehicle systems. These formulations are also used in developing upper and lower bounds on the volume of empty vehicle travel associated with other types of dispatching rules. It is shown that these bounds are significantly tighter than those reported in previous literature. Example problems are used to illustrate the bounding procedures.