针对飞行器再入飞行过程中存在的复杂气动环境和未知不确定干扰影响,在对扰动提出一定假设的基础上,提出一种基于自适应二阶非奇异终端滑模的控制方案,保证姿态跟踪误差在有限的时间内收敛于零的同时有效削弱控制舵机的抖振,提高系统控制精度。不需要内外扰的先验知识,通过在线自适应辨识扰动上界以消除其影响。最后以气动参数摄动50%作为扰动条件进行了飞行器再入姿态控制仿真,仿真结果表明控制系统消除了参数摄动影响及舵机抖振,因此具有较强鲁棒性。

On the basis of hypothesis, a robust adaptive flight control scheme based on second-order nonsingular terminal sliding mode control was proposed for the complex aerodynamic conditions and uncertain disturbances exist in aircraft re-entry. It can guarantee the tracking error converge to zero in finite time and weaken steering engine's chattering effectively. The effects cased by inside and outside unknown disturbances were cancelled by on-line upper bound adaptive identification without any information in advance. Finally, simulation was made through assumption that aerodynamic parameters perturb 50%. Simulation results show that the control system eliminates chattering of steering engine and the influence brought by parameters perturbation, so the robustness was proved.