Robust aeroelastic instability suppression of an advanced wing with model uncertainty in subsonic compressible flow field

Abstract

This paper addresses the robust aeroelastic instability suppression of an advanced aircraft wing modeled as a thin-walled beam structure with fiber-reinforced composite material featuring a circumferentially asymmetric stiffness (CAS) configuration. The unsteady aerodynamic loads in subsonic compressible flow are derived through the indicial function approach. Aeroelastic instability suppression is achieved via sliding mode control (SMC) based on sliding mode observer (SMO). To demonstrate the robustness of the SMC based on SMO, linear quadratic Gaussian (LQG) methodology is compared with respect to the model uncertainty. To this end, the obtained numerical simulation results emphasize the efficiency of the sliding mode control based on sliding mode observer to control the unstable aeroelastic phenomenon in conjunction with the model uncertainty.