Minimum risk planning for teams of unmanned air vehicles

A method for task assignment for persistent, low-altitude surveillance by a team of soaring-capable uninhabited air vehicles is discussed. The task assignment approach is based on minimizing the overall risk of mission failure (defined as failure to maintain continuous surveillance), where the risk to the mission of failure to perform a particular task defines the reward function in task assignment. Tasks include target surveillance, energy exploitation, exploration, and transit to target. Methods for assessing the risk of mission failure if each task is not performed are described and the Munkres algorithm is used for task assignment. Monte Carlo simulations show the utility of the proposed approach and the effect of flock size on the likelihood of mission failure is discussed.