IMPACT OF EMPTY VEHICLE FLOW ON OPTIMAL FLOW PATH DESIGN FOR UNIDIRECTIONAL AGV SYSTEMS

This paper addresses the flow path design issue of automated material handling systems. We concentrate on the design of unidirectional guide path for automated guided vehicle systems. We present a modelling app roach to determine the optimal flow path, which takes into account the impact of empty and loaded vehicle flows on the objective function to be minimized. We suggest a branch and bound algorithm, based on a dep th-first search, which gives the excellent results in a very reduced t ime. The presented modelling approach exploits the structure of the pr oblem to reduce the number of constraints by contraction and subtracti on. Computational performance of this algorithm is compared with a pro cedure developed by Kaspi and Tanchoco and Kim and Tanchoco.