A priority based conflict resolution approach for automated guided vehicles

Automated guided vehicle systems (AGVS) need to control large number of AGVs in time-critical applications where they are required to complete a number of tasks in real time. Whenever a conflict condition arises between two vehicles, successful resolution of conflicts becomes necessary in order to avoid collision. In this paper "priority based conflict resolution" strategies have been proposed to resolve the conflict. The collision avoidance of AGVs has been presented as a hybrid control problem assuming AGVs as "free". Two conflict resolution algorithms viz. "Conflict resolution without steering the controller vehicle" and "Conflict resolution by steering the controller vehicle" are proposed. The methodology proposed in the paper can be used to obtain safe sets of initial conditions for which the controllers will always guarantee collision free maneuver of controller vehicle. These safe sets can be used for deciding the routing for AGVs and can also be used for planning the layout of the floor and placing the stationary objects, machines etc. The strategies have been successfully verified on the example cases. The results obtained have also been illustrated through graphs in the paper