Adaptive backstepping control for a hypersonic vehicle with uncertain parameters and actuator faults

For a hypersonic vehicle with redundant elevators, an adaptive backstepping fault-tolerant control scheme is designed for its longitudinal motion model. In the backstepping design, the dynamic surface control strategy is adopted to eliminate the explosion of complexity in calculating the derivatives of virtual control inputs by introducing two first-order filters. An appropriate controller structure is proposed and the matching conditions are derived for adaptive fault compensation for the vehicle with redundant elevators subject to uncertain actuator faults. The adaptation laws are designed to update parameter estimates to implement the adaptive controller. The closed-loop stability under the proposed adaptive actuator fault compensation scheme is analyzed. Both analytical and simulation results are given to verify the effectiveness of the design and demonstrate the desired performance for altitude and velocity control.