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

Abstract

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.

Keywords

small body / hopping / pulse control / transfer distance