基于Backstepping和扰动观测器的导引律

考虑目标机动和自动驾驶仪动态特性等情况,基于扰动观测器(DOB)技术及Backstepping的设计思想,提出了一种新型的三维导引律。运用Backstepping的设计思想,将包含驾驶仪动态特性的制导环路分为外环和内环两个环路。将目标机动及俯仰和偏航平面间的交叉耦合项当成外环扰动,将驾驶仪参数不确定当成内环扰动,分别设计内外扰动观测器将它们估计出来,利用估计值做前馈补偿得到的外环控制器可抑制目标机动对制导精度的影响及实现两个平面的解耦控制,内环控制器补偿驾驶仪动态特性对制导精度的影响。导引律的设计在于使得导弹的实际加速度跟踪上外环的虚拟控制。仿真结果表明:在目标做大机动、考虑驾驶仪动态特性的情况下,这种导引律仍然具有良好的制导精度。

A Guidance Law Design Based on Disturbance Observer and Backstepping

This paper proposes a new guidance law which takes into consideration the guidance in cases of target maneuvers and autopilot dynamics and makes use of the disturbance observer (DOB) technology and the backstepping method. The guidance loop including the autopilot dynamics is divided into an outer loop and an inner loop. Target maneuvers and the cross coupling term of the pitch plane and the yaw plane are regarded as outer loop disturbances, while the autopilot parameter uncertainties are regarded as inner loop disturbances. The disturbance estimations derived by the disturbance observers are employed as feed-forward compensations to restrain the influence of target maneuver and autopilot dynamics on guidance performance, and they are also used to realize the decoupling of the two planes. A guidance law is designed to enable the actual acceleration of the missile to track the virtual control of the outer loop. Simulation results show that the proposed algorithm can achieve the goal of guidance effectively even when considering autopilot dynamics and highly maneuvering targets.