An algorithm for routeing control of a tandem automated guided vehicle system

Abstract

A tandem AGV (automated guided vehicle) system is composed of several non-overlapping closed loops. Stations within each loop are served by a single dedicated vehicle. The transit area located between two adjacent loops serves as an interface and allows loads to be transferred from one loop to another. If a load needs to be delivered to a station not located within the same loop, the load needs more than one vehicle to carry it to its destination. We regard this routeing problem as a problem of finding the shortest travel time. After a command to deliver a load is issued, finding a route from the source to the destination as rapidly as possible without disrupting other active travel schedules was the objective of this study. A task-list time-window algorithm to find a shortest travel time based on the current status to route a load from point A to point B is presented. Two idle-vehicle managements are considered: circulating (CIRC) and STAY policies. Experiments showed that the STAY policy is more efficient than the CIRC policy in routeing control.

Additional information

Notes on contributors

J. T. LIN

To whom correspondence should be addressed.