Tracking Control of Hypersonic Vehicle Considering Input Constraint

Abstract

This paper studies the tracking control problem of hypersonic vehicles under the circumstances of external disturbance, coupling response, and input constraint. First, on the basis of the input-output linearization model of the hypersonic vehicle, an auxiliary error variable is introduced to convert the original model into a second-order system model. Then a back-stepping controller is designed for the situation of external disturbance with a known upper bound. Because a consecutive nonlinear function is introduced in the virtual controller, the closed-loop system has a rapid convergence rate. In order to further solve the external disturbance with an unknown upper bound and input constraint, a robust adaptive back-stepping controller that meets the input constraint is proposed based on the command filter and adaptive theory. Finally, the Lyapunov theory is applied to give strict proofs of the designed controllers. A numerical simulation of the longitudinal dynamics model of the hypersonic vehicle is conducted to further confirm the validity and robustness of the controllers.