一种适用于高速拦截的滑模末制导律

实际导弹系统存在一系列的参数不确定性及外部扰动,而利用滑模变结构系统具有的抗干扰和抗参数摄动特性,可以设计出对干扰具有很好鲁棒性的滑模制导律（SMG）。但目前广泛采用的基于零化视线角率的滑模制导律在用于高速（高超声速）拦截情况时,由于相对速度大,视线角率在零点振荡剧烈,很容易导致系统的发散。针对这一问题,（西北工业大学航天学院）设计了一种新型滑模制导律,其并不要求时时将视线角率控制为零,而是随着弹目标距离的减小,自动适当地放宽对视线角率的约束,从而有效缓解了传统滑模制导带来的强振荡问题。最后通过某高超声速拦截导弹的六自由度拦截仿真来说明这种滑模制导律的性能。与传统滑模制导律相比,在高速拦截时,其制导指令的振荡问题得到明显缓解,同时还保留了滑模系统的鲁棒特性。

Sliding Mode Guidance Law for High Speed Interceptor

There are a series of uncertain parameters and external disturbance in actual missile system. The slide mode guidance law (SMG) can be designed with excellent robustness. But SMG used in engineering now is not applicable to high speed interceptor, because it is designed based on making the change of line of sight (LOS) become zero. When the relative velocity between missile and target is high, the change of the LOS will not be kept zero but vibrate. It can result in the system unsteady. A new SMG is designed. It do not request keeping the change of the LOS be zero all the time, but relax restriction advisably and automatically as missile approach target. A six degree-of-freedom simulation for a certain type hypersonic interceptor is given using the new SMG. The result shows that compared with the traditional SMG the new guidance law can reduce the command vibrated, and keep the robustness of the slide mode system at the same time.