Scalable System Approaches to Unmanned Aerial Vehicle Upset Prevention and Recovery Navy SBIR FY2005.2 Sol No.: Navy SBIR FY2005.2 Topic No.: N05-097 Topic Title: Scalable System Approaches to Unmanned Aerial Vehicle Upset Prevention and Recovery Proposal No.: N052-097-0384 Firm: Barron Associates, Inc. 1410 Sachem Place Suite 202 Charlottesville, Virginia 22901-2496 Contact: Jeffrey Monaco Phone: (434) 973-1215 Web Site: http://www.barron-associates.com Abstract: Wind shear, icing, wake vortices from ship superstructures or other aircraft, actuator malfunctions, or component failures can all contribute to upset conditions. For piloted aircraft, prevention of or recovery from these events is challenging because of the nonlinear dynamics encountered at angles of attack and sideslip outside of the normal flight envelope. The problems are magnified for unmanned aircraft given typical vehicle sizes, actuator bandwidth, and the absence of a pilot. The goal of our research is to develop the control technologies that enable unmanned aerial vehicles to perform flight-envelope protection and upset recovery autonomously. Reinforcement learning control is a core technology to design outer-loop controllers that affect situation-appropriate recovery within the problem constraints (structural loads, for example). Manual recovery practices and NATOPS procedures are also encoded in the design. Novel control devices can make air vehicles more resistant to departure by postponing the onset of flow separation at high angles of attack. Thus, we address the role of add-on actuators in the recovery control-system framework. These range from a flip-tail for a flight-test UAV to arrays of synthetic jets for a tailless UCAV. High-fidelity simulations of two dynamically dissimilar models are used to develop the technology in Phase I. Benefits: The proposed product is a scalable system for autonomous upset recovery of various classes of UAVs. The R&D shows, by construction, that the system can assimilate information about the aerodynamic characteristics, flight controls, flying qualities, structural limits, and other relevant constraints to recover from the upset modes that are unique to the different vehicles considered. The proposed work demonstrates that our system can flexibly integrate control algorithm and hardware configurations to address the technical and practical/implementation considerations for a given platform and its concept of operations. If provable, the ability to accommodate unique control software and hardware requirements has obvious commercialization arguments for long-term US Navy UAV and UCAV platforms, UAVs presently in consideration by the US Navy (BAMS, VTUAV, J-UCAS), in-service UAVs (Predator), and existing, civilian flight test UAVs. This flexibility means that certain configurations can also be transitioned, in principle, to commercial transport aircraft to provide some level of autonomous upset recovery. Return