Abstract:The saturation of control surfaces is more likely to occur for the hypersonic vehicle (HSV) during reentry, and the dynamic model of HSV possesses the feature of strong uncertainty. Both problems make the design of reentry attitude controller a challenging task. The method of external anti-windup system combined with the second-order terminal sliding mode control law is presented for the nonlinear control problem of the restriction of control surfaces. It can realize the compensation for the control surface saturation and let HSV smoothly track the command signals. Then, the adaptive sliding mode disturbance observer (ASMDO) is proposed to estimate aerodynamic parameter uncertainties and strong external disturbances for strong uncertainty. This method does not need the information of disturbance bounds and has fewer learning parameters, so it is suitable for the real-time control. Finally, the simulation of attitude control for the reentry HSV is conducted, and the results show the effectiveness and robustness of this scheme.