Feng Cong, Wang Qing, Liu Chen, Hu Changhua, Liang Xiaohui
Department of Automation Science and Electrical Engineering, Beihang University, Beijing 100191, China.
Science and Technology on Special System Simulation Laboratory, Beijing Simulation Center, Beijing 100854, China.
Sensors (Basel). 2020 Feb 5;20(3):848. doi: 10.3390/s20030848.
This study is concerned with the attitude control problem of variable-structure near-space vehicles (VSNSVs) with time-varying state constraints based on switched nonlinear system. The full states of vehicles are constrained in the bounded sets with asymmetric time-varying boundaries. Firstly, considering modeling uncertainties and external disturbances, an extended state observer (ESO), including two distinct linear regions, is proposed with the advantage of avoiding the peaking value problem. The disturbance observer is utilized to estimate the total disturbances of the attitude angle and angular rate subsystems, which are described in switched nonlinear systems. Then, based on the estimation values, the asymmetric time-varying barrier Lyapunov function (BLF) is employed to construct the active disturbance rejection controller, which can ensure the full state constraints are not violated. Furthermore, to resolve the 'explosion of complexity' problem in backstepping control, a modified dynamic surface control is proposed. Rigorous stability analysis is given to prove that all signals of the closed-loop system are bounded. Numerical simulations are carried out to demonstrate the effectiveness of the proposed control scheme.
本研究关注基于切换非线性系统的具有时变状态约束的变结构近空间飞行器（VSNSV）的姿态控制问题。飞行器的全状态被约束在具有不对称时变边界的有界集合内。首先，考虑建模不确定性和外部干扰，提出了一种具有两个不同线性区域的扩展状态观测器（ESO），其优点是避免了峰值问题。利用干扰观测器来估计姿态角和角速率子系统的总干扰，这些子系统在切换非线性系统中进行描述。然后，基于估计值，采用非对称时变障碍Lyapunov函数（BLF）来构造主动干扰抑制控制器，该控制器可确保不违反全状态约束。此外，为解决反步控制中的“复杂性爆炸”问题，提出了一种改进的动态面控制。进行了严格的稳定性分析，以证明闭环系统的所有信号都是有界的。进行了数值仿真以验证所提出控制方案的有效性。
