Novel linear parameter-varying modeling and flutter suppression control of a smart airfoil

In this article, two novel linear parameter-varying modeling and control techniques are proposed for active flutter suppression of a smart airfoil model. The smart airfoil model is instrumented with a moving mass that can be used to actively control the airfoil pitching and plunging motions. The first linear parameter-varying modeling approach makes use of the moving mass position as a scheduling parameter, and the hard constraint at the boundaries is imposed by proper selection of the parameter-varying function. The second modeling technique utilizes nonlinear springs and dampers, which are added to both ends of the airfoil groove to confine the motion of the moving mass. A state-feedback-based linear parameter-varying gain-scheduling controller with the guaranteed H infinity performance is proposed by utilizing the dynamics of the moving mass. In this study, both the position of the moving mass and the free-stream airspeed are considered as the scheduling parameters. The numerical simulations demonstrate the effectiveness of the proposed linear parameter-varying control architectures by significantly improving the performance, while increasing the flutter speed and reducing the control effort.