Design of dynamic sliding mode controller to aeroelastic systems

It is well known that for the model with a single trailing-edge control surface, trajectory control of either the plunge displacement or the pitch angle (but not of both) can be achieve by the controller design and there exist internal dynamics describing the residual motion in aeroelastic closed-loop systems. The internal dynamics of aeroelastic depend on the model parameters including the free stream velocity and spring constant. Motivated by the limited effectives of using single control surface, improvements in control of limit-cycle oscillation by using leadingand trailing-edge control surface are investigated. Moreover, two control surfaces provide flexibility in shaping both the plunge and the pitch responses. This study uses the dynamic sliding mode control (DSMC) to achieve system stability and eliminate the phenomenon of limit cycle response. Compared to the conventional sliding mode control design, the proposed control law preserves not only the robustness of the system but also avoids chattering phenomenon. Simulation results are presented which show that these controllers are effective in regulating the response to origin in state space in spite of controller input with saturation.