Recent aeroservoelastic research at Texas A&M University has involved the use of a trailing-edge control surface (or flap) in order to suppress aeroelastic instabilities such as flutter phenomena. While the controller for the trailing-edge control surface proves effective, studies show that the addition of a leading-edge control surface will further improve the ability to control high amplitude oscillations in the presence of gust disturbances. A leading-edge control surface actuator system of approximately one-third of the full wingspan is installed onto an aeroelastic wing already containing a full-span trailing-edge control surface. Aerodynamic flow sensing in real time is performed by tracking the leading-edge stagnation point using hot-film sensors mounted mid-span on the wing's leading-edge. Using the leading-edge stagnation point to determine aerodynamic loads is shown to be as accurate as using the load sensor. The Nonlinear Aeroelastic Test Apparatus at Texas A&M University allows for free pitch and plunge motions, and a gust generator upstream of the wing creates gust disturbances. Using similar control techniques for the leading-edge and trailing-edge control surfaces as those with the trailing-edge control surface alone, high amplitude oscillations are suppressed in the presence of gust disturbances. Improvement is seen in activating both the leading-edge and trailing-edge controllers over strictly the trailing-edge controller in gust load alleviation tests.
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