Short and full horizon motion planning for persistent multi-UAV surveillance with energy and communication constraints

The strong resource limitations of unmanned aerial vehicles (UAVs) pose various challenges for UAV applications. In persistent multi-UAV surveillance, several UAVs with limited communication range and flight time have to repeatedly visit sensing locations while maintaining a multi-hop connection to the base station. In order to achieve persistence, the UAVs need to fly back to the base station in time for recharge. However, simple motion planning algorithms can result in mutual movement obstructions of UAVs caused by the constraints. We introduce two planning algorithms with different planning horizons and cooperation and compare their performance in simulation studies. It can be seen that the short horizon uncooperative strategy can outperform other strategies if a sufficient number of UAVs is used. The full horizon strategy can generate a solution visiting all sensing locations if the existence conditions for such a solution are fulfilled.