Description: DynSan proposes to develop a flight controller that will preserve the aircraft trajectory while directing to sources of potential updrafts to optimize fuel consumption of Unmanned Aircraft Vehicles (UAV). Fuel consumption represents a significant factor in powered flight operations; it is desirable therefore to limit the fuel consumption in order to extend an aircraft's flight range and/or flight duration. Glider pilots use their knowledge in micrometeorology to locate and exploit sources of lift. The same soaring techniques could be used with UAV, to exploit atmospheric energy that is renewable. The exploitation of this source of energy can be automated using a controller that will correct the aircraft trajectory in order to optimize the climb rate and thus the average cruising speed. Dynamic soaring is the final source of energy that exploits the differential wind velocity at different heights. In Phase I, we propose to build a map of potential updrafts based on terrain and meteorological conditions and test the validity of this map using actual data extracted from sailplane contests. The data will provide the horizontal and vertical glider speeds; using glider polars will allow us to extract information of the vertical movement of the surrounding airmass. This information will be used by a novel controller that will direct the UAV through locations or rising air, while keeping the aircraft on trajectory to target. The flight of a model UAV through selected topographic and atmospheric conditions will be simulated. Comparisons to actual archived flight data will be made. In Phase II, we will fabricate, program and integrate the developed controller on a real UAV. With the UAV equipped with cameras, it will be possible to visually locate the updraft columns that are marked by fair weather cumulus clouds and manually direct the UAV to such columns. The controller performance in optimizing the aircraft climb rate will then be tested.

Benefits: NASA will be able to develop novel UAVs that will exploit atmospheric features and increase the efficiency of these aircraft. Moreover NASA expressed a need for improving dropsondes. In order to explore more efficiently atmospheric features, these dropsondes need to be guided. The technology developed in this proposal can be applied to these devices.

The development of an autopilot optimizing the fuel consumption is of interest to the civilian and military market. Usage of UAVs by military forces is rapidly accelerating. One of the advantages of unmanned systems is that they can be very light since they do not need to carry a pilot. When unmanned aircraft are piloted from the ground, the communication can be intercepted and the aircraft cannot remain stealthy. Therefore, it is desirable for a UAV to fly autonomously for the longest period of time. Our approach that allows the aircraft to fly autonomously for extended periods of time has strong support from Boeing and Lockheed-Martin (see letters of support at end of proposal) and can be used with their fleet of vehicles such as the K-MAX, Desert Hawk III, Sky Spirit, SURGE-V, EER, Samurai, and Nighthawk Micro UAVs.