Flutter suppression of a high aspect-ratio wing with multiple control surfaces

This paper presents a systematic study on active flutter suppression of a high aspect-ratio wing with multiple control surfaces distributed throughout the span. The dynamic characterization of the wing structure is done by the finite element method. Doublet lattice method is used to model unsteady aerodynamic loads acting on the lifting surface with leading-edge and trailing-edge control surfaces. The open-loop aeroelastic equations with input delays are established by the modal transformation of the structural equations and the minimum state approximation of the aerodynamic influence coefficient matrix. To suppress flutter of the time-delayed system, a dynamic controller is synthesized in H-infinity control theory framework. The delay-dependent stability of the closed-loop system is analyzed by tracing the rightmost eigenvalues of the system. Numerical simulations are made to demonstrate the effectiveness of all the above approaches. (C) 2009 Elsevier Ltd. All rights reserved.