Online scheduling of a multi-robot system by using genetic algorithms

Abstract

This paper proposes an online method to schedule the movement of robots in a multi-robot system. The authors introduce a multi-agent based search method to cope with small modifications of the system during the execution of a schedule which is preliminarily obtained by a genetic algorithm (GA). They apply the method to a welding plant, in which a number of seams are processed simultaneously by several robots, but there is no one-to-one relation between the seems and the robots. A GA is used to assign the welded seams to the robots and to schedule the welding order of the seams of each robot in a way which minimizes the overall welding time. The task of the proposed multi-agent based search method is to cope with troubles of the robots and sudden changes of the seams for which a online modification of the schedule is necessary. As a result of computer simulations, the proposed method shows fairly good results for perturbations in the system during the task.