An energy-based optimal control problem for unmanned aircraft systems flight planning

In this paper, we formulate the flight planning problem for a multirotor Unmanned Aircraft Systems (UAS) as an optimal control problem. The cost optimized is the energy consumption at the cruise phase of a mission. We first present a general formulation, then address a special cases: optimizing flight directions given vehicle speed. The problem was solved numerically on digital elevation models (DEM) with the Ordered Upwind Method (OUM). By combining the optimized path with timestamps, we can generate 4D trajectories typically used in aviation flight planning, and thus maximize the software compatibility between manned and unmanned aviation. Simulation shows that the algorithm can generate energy-optimal paths avoiding obstacles, as well as estimate energy consumption along the entire trajectory.