A novel reduced-order guidance and control scheme for hypersonic gliding vehicles

Abstract A novel analytical model between roll, pitch rates and components of acceleration of the hypersonic vehicle is established, and a reduced-order gliding guidance and control (G&C) design approach for the hypersonic vehicle is proposed in this paper. The six-degree-of-freedom (6DOF) dynamical and kinematical equations of the hypersonic vehicle in the gliding phase are described. An analytical model suitable for the bank to turn (BTT) control strategy is derived by connecting body rates with components of acceleration in the ballistic coordinate system. A novel reduced-order guidance and control design model with respect to quasi-equilibrium gliding flight is deduced and converted into the strict feedback form. The three channel body rates are treated as pseudo-inputs for tracking errors of flight path angle and heading angle of the hypersonic vehicle. Then, the commanded control surface fin deflections of the hypersonic vehicle are obtained by controlling tracking errors of the flight path angle, heading angle, and the body rates by adopting the block dynamic surface control method. In this paper, the aerodynamic coefficient interpolation process for obtaining the commanded angle of attack and bank angle based on expectant guidance overload is avoided. Meanwhile, the control loop of tracking Euler angles for getting the desired body rates is also elided. Finally, effectiveness and robustness of the novel G&C design method are verified and investigated. Moreover, the feasibility of entering quasi-equilibrium gliding phase only depending on the aerodynamic control mechanism is discussed.