UAV Flight Control for Artificial Icing Testing

Further work in the design, simulation and evaluation of flight control system components for artificial icing testing of UAVs behind the Army's CH-47 Helicopter In-flight Spray System (HISS) aircraft is described. The goals of the system are to provide autonomous approach, formation flight station-keeping, and egress for a UAV operating behind the spray boom of the HISS to ensure efficient and effective icing performance testing of the vehicle, while maintaining safe operation of the UAV in the close proximity of manned aircraft. The flight control system blends differential GPS positioning information from the HISS aircraft and the UAV under test, with inertial measurement unit data to provide smoothed, accurate relative position and orientation data for use in flight path regulation and positioning control. This effort, funded as an Armysponsored SBIR project, involved the selection of the sensors, control computers, and algorithm development for flight control command generation. Analysis of the flight control system and its subcomponents relied upon a detailed simulation of the formation flight environment hosted within a MATLAB environment, which includes a detailed rotor response and vehicle loads analysis, and options for use in real-time flight simulations that may incorporate notional flight hardware-inthe- loop for evaluation.