带攻角约束的高超声速飞行器自适应反步控制器设计

针对带攻角(AOA)约束的高超声速飞行器控制问题，提出一种基于非对称时变障碍函数的非线性自适应反步控制方法。首先，将飞行器模型化为严反馈形式，以反步法为基础进行控制器设计。然后通过光滑饱和函数对名义攻角指令信号进行限幅，并保证限幅信号的可导性，限幅产生的误差通过设计辅助系统进行补偿。进而使用障碍函数对攻角指令跟踪误差进行非对称时变约束。针对不确定性和干扰，设计新型自适应律对集中干扰上界进行估计并补偿。最终通过Lyapunov理论证明了闭环系统状态量一致最终有界并且攻角始终满足时变约束。仿真结果表明，本文方法能够在满足攻角约束基础上保证良好跟踪性能。

Adaptive Backstepping Controller Design for Hypersonic Vehicle with Limited Angle of Attack

A new adaptive backstepping controller is proposed for a hypersonic vehicle with limited angle-of-attack(AOA). Firstly, the vehicle model is rewritten into a strict-feedback form so that backstepping can be employed in the design process. Then a smooth saturation function is introduced to restrict the nominal AOA into the prescribed range and the filtered signal remains differentiable. Moreover, the filtering error is compensated with an auxiliary system. Further, the asymmetric time-varying barrier function is utilized to constrain the virtual AOA command. Regarding the uncertainties and disturbances, the novel adaptive laws are built to estimate the upper bounds of the lumped disturbances. Finally, the stability of the closed-loop system is proved based on the Lyapunov theory. All the signals are uniformly ultimate bounded and time-varying AOA constraint is guaranteed. The simulation results show that the proposed controller can guarantee good tracking performances with limited AOA.