基于滑模控制的制导方法研究

Research on the Guidance Law Based on Sliding Mode Control

针对空地导弹末制导段终端角约束问题,根据滑模控制理论,设计了加速度控制指令垂直于弹目视线方向的制导规律。从建立末制导过程中导弹和目标间的动力学方程入手,推导出以视线角和视线角速度为状态量的状态方程,构建了一个滑模面,在这个滑模面上弹目视线角和期望的终端角之差与弹目视线角速度为零。又引入Lyapunov函数驱动系统达到所设计的滑模面,综上推导出控制加速度的表达形式。该导引律在满足终端角要求的同时,能进一步增大导弹击顶速度。最后,在MATLAB环境下构建了几种仿真场景,仿真结果表明该制导律的有效性。

Considering the terminal impact angle of air-to-ground missile,a novel guidance law is proposed based on the sliding mode control theory. Firstly,nonlinear dynamics of the engagement geometry between the missile and target is studies,and deriving the state equations for the line-of-sight angle and its rate. Then a sliding manifold is proposed which drives the difference value between line-of-sight angle and the desired terminal impact angle and LOS rate to zero. Then Robust Control Lyapunov Function is introduced to the system to control the system towards defined sliding manifold. To sum up,the command is calculated. The proposed guidance law can satisfy terminal impact angle constraints and increase the terminal velocity. Finally,several simulation scenarios are presented in the MATLAB environment,the simulation results validate the performance of the guidance law.