自适应模糊滑模变结构制导律研究

Study of fuzzy adaptive sliding-mode control guidance law

针对拦截高速机动目标的目的,基于平行制导的方法,提出了一种具有强鲁棒性的模糊自适应滑模制导律,使用自适应模糊推理机来逼近引起抖振的变结构控制的符号项,通过Lyapunov函数证明了其稳定性。此控制律可以应用于仅有视线角速率、目标机动且其加速度无法测量的导弹制导系统。利用自适应模糊系统的万能逼近能力以任意精度进行逼近系统中未知函数,克服了系统模型不确定性和外界干扰对制导控制系统的影响。仿真表明,所设计的制导律能够有效的减弱系统抖振,并保证了系统的鲁棒性和较小的脱靶量。

For intercepting high speed target,an adaptive fuzzy sliding mode guidance law with strong robustness is proposed based on parallel guidance law. Adaptive fuzzy inference engine is used to approximate the signum function of sliding- mode control. Using Lyapunov stability theory,the guidance law is proved to be stable. This guidance law can be used in missile guidance system which there is only measured line-of-sight angular rate and the target＇ s acceleration is unknown. The universal approximation ability of adaptive fuzzy system is used to approximate the unknown function in the missile guidance systems to overcome the influence of model uncertainty and external disturbance. Simulation results show that the line-of-sight angular rate is not chattering and the miss distance is smaller by applying the guidance law. So it ensures the system have higher guiding precision and robustness.