针对高度非线性、多变量、强耦合的高超声速飞行器的纵向模型,设计了飞行控制系统。首先对其进行输入/输出线性化,然后,选择2个解耦的滑动面,以改进的符号函数作为到达条件,设计了一种多输入多输出滑模变结构控制器。分别研究了飞行器对速度和高度阶跃指令下的响应,对标称模型和含有大范围时变参数模型进行了仿真研究。仿真结果表明该方法在存在参数不确定性的条件下,具有较强的鲁棒性能,能够满足系统的性能要求。
Considering nonlinear,multivariable and strong coupled longitudinal mode of hypersonic aircraft,the plant flight control system is designed.First,the hypersonic vehicle mode is transformed into an affine system through input-output feedback linearization.Then,A multi-input/multi-output sliding mode controller is designed by selecting two decoupled sliding surfaces and the improved sign function is used as the reaching condition.The response of the vehicle under speed and high step instruction is studied.The comparison between the nominal model and the model with time varying parameters over large ranges is made.The simulation results show that the method has strong robustness and can meet the system performance requirements under the condition of uncertain parameters.