月球引力转弯软着陆的制导控制研究

对于月球引力转弯软着陆过程 ,采用反馈线性化方法 ,对高度和速度信息分别设计了跟踪制导控制律 ,并应用微分几何的有关理论证明了这两种跟踪制导控制系统的李雅普诺夫稳定性。此外 ,根据软着陆系统推力、燃料和状态的约束条件 ,给出了引力转弯着陆过程初始条件的可达集合。最后给出的软着陆跟踪制导实例 ,只需要测得斜向距离、速度和姿态角度信息。这种制导方法测量简单 ,适于低成本的软着陆任务。

Guidance Control for Lunar Gravity-Turn Descent

The feedback linearization method is utilized to generate guidance laws to track desired height and velocity profiles respectively for lunar gravity-turn descent.The Lyapunov stability of the two following control systems is demonstrated in use of related theory of differential geometry.Furthermore,an attainable set for initial conditions of the gravity-turn descent is deduced according to the constraints of thrust,fuel and states of the soft landing system.Finally,an example of the following guidance law is presented,which needs only slant range,velocity and local vertical information.This method may allow simple guidance with less complex sensors for low-cost soft landing on the lunar surface.