Command filter based robust nonlinear control of hypersonic aircraft with magnitude constraints on states and actuators

The command filter based robust nonlinear controller is designed for the longitudinal dynamics of a generic hypersonic aircraft in presence of parametric model uncertainty and magnitude constraints on the states and actuators. The functional subsystems are transformed into the linearly parameterized form and the controller is proposed based on dynamic inversion and adaptive gain. Since the dynamics are with cascade structure, the states are considered as virtual control and the signal is filtered to produce the limited command signal and its derivative. To eliminate the effect of the constraint, the auxiliary error compensation design is employed and the parameter projection estimation is proposed based on the compensated tracking error. The uniformly ultimately boundedness is guaranteed for the closedloop control system. Simulation results show that the proposed approach achieves good tracking performance.