Feasibility-aware Hierarchical Task Assignment for Equipment Inspection Robots with Heterogeneous Work

In this paper, we address optimal task assignments for equipment inspection robots in a factory. In view of the complex work environment and variety of the devices to be inspected, coordination of heterogeneous robots is inevitable for such a system. In this paper, we propose a computationally efficient hierarchical optimization architecture for a robotic team with heterogeneous work efficiency, where the upper layer assigns robots to subareas and the lower assigns them to target devices together with the inspection items. In order to ensure feasibility of the lower-layer optimization, we present novel logical constraints for the upper-layer problem such that enough robotic resources are reserved at each time frame, while showing that the resources used in the past can be kept track of by a dynamic constraint. Finally, we demonstrate the effectiveness of the present solution through simulation that duplicates operations in an actual factory.