An analytical nonlinear predictive controller for wing rock suppression

Wing rock suppression, which is essentially a finite horizon nonlinear control problem, plays an important role in flight control for modern aircraft. A new nonlinear predictive control algorithm is proposed to suppress the wing rock motion. Using this algorithm, the wing rock suppression problem is transformed into the system output tracking problem. First, Based on the relative degree of output with respect to the control input, the predicted tracking error is expressed as a truncated Taylor series dependent on the control input. The control input is then selected to minimize a cost function related to the predicted error. The executed command is obtained by correcting the optimal control input according to the limitation of Reaction Control System (RCS). At last, the predictive controller is tested in different working conditions, and is compared with other controllers in literature. The simulation results indicate that the nonlinear predictive controller is of superior performance.