UAV surveillance mission planning with gimbaled sensors

In this paper, the problem of mission planning with UAVs for urban surveillance is studied. The target is to guide a group of UAVs equipped with cameras to fly over an urban area (possibly hostile) to provide complete surveillance coverage in an optimal manner. The camera, mounted on gimbals fixed to the UAVs, has the capability of panning and tilting. Thus, not only the trajectory of the UAVs, but also the schedule for orienting the camera axis needs to be provided in the mission plan. The problem is solved with a two-stage approach. In the first stage, a set of candidate camera configurations (location + camera axis) are identified. The sum of coverage of these camera configurations forms a super set for covering the target area. In the second stage, the optimal set of camera configurations, called the vantage set, is constructed from the super set. On one hand, the vantage set ensures complete coverage. On the other, it also leads to lowest flying cost with the available UAVs. Evolutionary algorithms (PSO and GA respectively) have been developed for optimization in both stages. Different fitness functions have been established to deal with situations with/without enemy presence.