基于变结构控制的固定前置角制导律设计

Design of Heading Angle Guidance Law Based on Variable Structure Control Theory

弹载合成孔径雷达(SAR)的方位成像能力受飞行导弹的观测角影响,其末制导段采用前侧视工作方式;因此,必需合理设计制导律使前侧视条件成立;为了保证末制导段弹目间具有合适的夹角,采用变结构控制方法设计了一种固定前置角制导律,该制导律能够解决合成孔径雷达导引头对于前置角约束的问题;在制导律设计过程中,首先建立了弹目相对运动关系模型和具有终端角度约束时的视线角变化模型;在此基础上采用变结构控制的方法设计了固定前置角制导律;进而,对该固定前置角导引律进行了性能分析,得出了其一般攻击特性;最后,通过弹道仿真论证了其正确性与有效性。

For synthetic aperture radar seeker,the trajectory and the viewing angle have an effect on the azimuth resolution of imaging.As the terminal guidance phase using squint mode,guidance law must be designed rationally to satisfy squint condition.Based on variable structure theory,pre-fixed angle guidance law is designed.The guidance law proposed could solve the constraint problem of synthetic aperture radar seeker effectively.In designing the guidance law,missile-target relative motion model and sight angle variation model with terminal angle constraint are built at first.On this basis,pre-fixed angle guidance law is designed by variable structure control method.Then,the performance analysis on pre-fixed angle guidance law is carried on,and the general attack characteristic is obtained.At last,correctness and effectiveness of the method are verified through the simulation.