Trajectory Optimization of Solar-Powered High-Altitude Long Endurance Aircraft

Solar-powered aircraft can fly perpetually if they are able to fly a 24-hour mission in which they collect more energy than they expend. The energy collected is determined by the orientation and length of time that the aircraft's solar panels are exposed to the sun. The energy spent is determined by flight maneuvers such as changes in airspeed, altitude and heading. Therefore, a perpetual energy balance can be maintained when the aircraft flies along a trajectory that maximizes solar exposure and minimizes flight maneuvers. This paper presents a faster than real-time dynamic programming strategy that computes the optimal trajectory that contains a loitering aircraft inside a cylindrical volume placed about a reference waypoint.