空空导弹大攻角俯仰自动驾驶仪设计

Design of Pitch Autopilot of High Angle of Attack for Air-to-Air Missile

研究导弹自动驾驶仪优化控制问题,针对空空导弹在大攻角飞行过程中,系统的空气动力学特性存在强非线性耦合和参数不确定性,引起系统稳定性差。为了提高系统性能,在导弹俯仰运动的非线性数学模型的基础上,以导弹攻角为被控信号,舵偏角指令为输入信号,提出采用反馈线性化方法对导弹模型进行线性化,然后运用变结构控制理论进行控制器设计。控制器结构简单,易于实现,能够抑制被控对象中存在的不确定性。并通过数学仿真与全状态反馈控制方法设计的控制器进行了比较。结果表明采用反馈线性化和滑模变结构方法设计的控制系统对气动参数摄动和外部扰动具有较强的鲁棒性。

High nonlinear coupling and parameter uncertainty exist in high angle attack flying for air-to-air mis- sile. A feedback linearization method was used to linearize the missile model based on the nonlinear model of pitch motion for air-to-air missile in this paper with nonlinear characteristic in high angle attack flying, in which the angle of attack was served as the output and command of the fin deflection as its input. Then a variable structure controller was designed based on the theory of sliding mode control. The structure of the controller is simple and easy to realize, and the controller can restrain the uncertainties existing in the controlled device. Using the simulation, the compari- son was played between the controller designed based on full state feedback method and feedback linearization meth- od. The contrast results showed that using the methods of the feedback linearization and the sliding mode of the varia- ble structure, the designed control system was of robustness to the perturbation of aerodynamic parameters and the ex- terior disturbance.