小天体安全着陆与表面探测控制方法研究

针对探测器在小天体表面的弹跳式运动特点，提出一种表面运动控制方法。首先基于简化的运动模型，计算出探测器进行弹跳式转移所需的初始速度；然后通过对轨道方程的线性化，基于线性时变系统的求解方程，采用脉冲控制对每次弹跳的运动轨迹进行修正，增加控制精度；并分析转移距离与弹跳次数的关系；最后，以小行星1620 Geographos作为目标小天体进行仿真分析，验证了控制算法的有效性。结果表明，该控制方法可以应用于探测器在附着到小天体表面后的弹跳转移，也适用于弱引力环境下探测器的弹跳式探测。

A Pulse Control Strategy of Landers for Hopping Exploration on Small Bodies

Surface investigation is an effect way to improve the cognition of small bodies for human being. Considering the impacts of the irregular micro-gravity near small bodies,the lander may bounce above the surface when touches down which is a dangerous situation for landing. Meanwhile,the movement of the surface detector is generally achieved by hopping ways. In this paper,a pulse control strategy is developed in order to improve the stability and accuracy for small body landing and long-distance transfer,and the corresponding guidance law is developed. This control strategy can be used for the scenarios of both re-landing and multi-hopping exploration on a small body. Firstly,the velocity pulse is exerted at the initial points if the transfer is needed. Such velocity pulse can be computed based on the parabolic movement. Then,the trajectories are corrected based on the pulse control. The proposed guidance law is flexible enough to be implemented in real time for small body landers. To certificate the performance of the proposed control strategy,simulations are conducted and the effectiveness and accuracy are analyzed.