Integrated control laws are developed for stability augmentation and active fluttersuppression (AFS) of a flexible, flying-wing drone. The vehicle is a 12-pound unmanned, flying-wing research aircraft with a 10 ft wingspan. AFS is flight critical since the subject vehicle isdesigned to flutter within its flight envelope. The critical flutter condition involves aeroelasticinteractions between the rigid-body and elastic degrees of freedom; hence the control laws mustsimultaneously address both rigid-body stability augmentation and flutter suppression. Thecontrol-synthesis approach is motivated by the concept of Identically Located Force andAcceleration (ILAF), successfully applied on some previous operational aircraft. Based on theflutter characteristics and on conventional stability-augmentation concepts, two simple loopclosures are suggested. It is shown that this control architecture robustly stabilizes the body-freedom-flutter condition, increases the damping of the second aeroelastic mode (which becomesa second flutter mode at higher velocity), and provides reasonably conventional vehicle pitch-attitude response. The critical factors limiting the performance of the feedback system areidentified to be the bandwidth of the surface actuators and the pitch effectiveness of the controlsurfaces.
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