Journal of Vibration and Sound

Journal of Vibration and Sound

Body Freedom Flutter Suppression Using LQR Controller

Document Type : research article

Authors
Salman Shafaghat 1
Mohammadali Noorian 2
saied irani 3
1 Aerospace Faculty, Malek Ashtar University of technology
2 Aerospace Faculty, K. N. Toosi University of Technology,
3 Aerospace Faculty, K.N.Toosi University of Technology
Abstract
The body freedom flutter phenomenon is one of the aeroelastic instabilities that occurs due to the coupling of the aeroelastic bending mode of the wing with the short-period mode in the flight dynamics of the aircraft. By using the aeroservoelastic model and applying closed loop control, this phenomenon can be suppressed in the operating conditions of the aircraft and the velocity of this event can be increased. The simplest model aircraft capable of displaying this instability includes the flexible wing and the planar flight dynamics model. For this purpose, the wing structure is modeled using the Euler-Bernoulli beam and, the theory of minimum variable state is used to model unstable aerodynamics to make the conditions suitable for modeling the system in state space. In the control section, the elevator is used as the control surface and LQR theory with Kalman filter is used to body freedom flutter suppression. Finally, the effect of adding a closed loop control to increase the body freedom flutter velocity and the limitations of this work are studied.
Keywords
Aeroelasticity
Full airplane model
Body Freedom Flutter (BFF)
minimum state method
LQR Controller
Subjects
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Journal of Vibration and Sound
Volume 13, Issue 25 - Serial Number 25
September 2024
Pages 50-64