Piecewise analytic optimized ascent trajectory design and robust adaptive finite-time tracking control for hypersonic boost-glide vehicle

Abstract

This paper proposes a novel robust real-time trajectory optimization method to obtain the analytic solutions for hypersonic boost-glide vehicle (HBGV), and the corresponding robust adaptive controller is designed to lead the tracking error to a small neighborhood near zero in finite time. The cost functions reflect the constraints and the direction of trajectory optimization about several essential traits, such as dynamic pressure, load factor, heat flux and thrust. Through the conditions on continuity and constraints at the joint points, the parameters of piecewise analytic ascent trajectory could be automatically modulated. Additionally, the real-time robustness of the analytic trajectory is guaranteed by replacing initial values with current states. Then, the referenced program pitch angle with far more practical application value for tracking problem is exported. Next, a controller integrating nonsingular terminal sliding mode control (NTSMC) with adaptive control is employed to guarantee that the closed-loop tracking system is robust under time-varying uncertainties with unknown bounds. The finite-time convergence is theoretically proved by detailed analyses on Lyapunov functions. In the end, simulation results demonstrate the feasibility of the piecewise analytic optimized ascent trajectory and the validity of the tracking controller in comparison with NTSMC and proportional derivative (PD) control.