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This paper describes the design of guaranteed transient performance based attitude control for the near space vehicle (NSV) with control input saturation using the backstepping method. To improve the robust controllability of the NSV, the parameter adaptive method is used to tackle the integrated effect of unknown time-varying disturbance and control input saturation. Based on the backstepping technique and parameter estimated outputs, a robust attitude control scheme is proposed for the NSV with input saturation. A novel robust attitude control scheme is then proposed based on a prescribed performance bound (PPB) which characterizes the convergence rate and maximum overshoot of the attitude tracking error. The closed-loop system stability under both the developed robust attitude control schemes is proved using Lyapunov's method and uniformly asymptotical convergence of all closed-loop signals is guaranteed. Finally, simulation results are given to show the effectiveness of both the proposed robust constrained attitude control schemes.

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The control law design for a near-space hypersonic vehicle (NHV) is highly challenging due to its inherent nonlinearity, plant uncertainties and sensitivity to disturbances. This paper presents a novel functional link network (FLN) control method for an NHV with dynamical thrust and parameter uncertainties. The approach devises a new partially-feedback-functional-link-network (PFFLN) adaptive law and combines it with the nonlinear generalized predictive control (NGPC) algorithm. The PFFLN is employed for approximating uncertainties in flight. Its weights are online tuned based on Lyapunov stability theorem for the first time. The learning process does not need any offline training phase. Additionally, a robust controller with an adaptive gain is designed to offset the approximation error. Finally, simulation results show a satisfactory performance for the NHV attitude tracking, and also illustrate the controller's robustness.

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