Robust control of a nonlinear aeroelastic system using dynamic integral sliding mode control method

This paper presents an adaptive active control method, which is applied for the flutter suppression of a structurally nonlinear wing section with softening spring structure. Firstly, a dynamic integral sliding mode control (DISMC) is introduced to achieve system stability and eliminate the phenomenon of limit cycle response. In order to choose a suitable integral sliding surface, the regulator theory is effectively used through implementation of the Linear Quadratic Regulator (LQR) control methodology. Secondly, the proposed dynamic sliding mode control guarantees the convergence of flutter with the incorporation of integral saturation compensation based on Lyapunov theory. Lastly, a comparison carried out with a second-order sliding mode control with backstepping demonstrates the superiority of the proposed control law. Simulation results indicate that the close-loop system with DISMC can preserve the robustness of the system in the presence of uncertainties although the controller input was limited.