Asteroid rotation and orbit control via laser ablation

This paper presents an approach to control the rotational motion of an asteroid while a spacecraft is deflecting its trajectory through laser ablation. During the deflection, the proximity motion of the spacecraft is coupled with the orbital and rotational motion of the asteroid. The combination of the deflection acceleration, solar radiation pressure, gravity field and plume impingement will force the spacecraft to drift away from the asteroid. In turn, a variation of the motion of the spacecraft produces a change in the modulus and direction of the deflection action which modifies the rotational and orbital motion of the asteroid. An on-board state estimation and control algorithm is then presented that simultaneously provides an optimal proximity control and a control of the rotational motion of the asteroid. It will be shown that the simultaneous control of the rotational and proximity motions of asteroid and spacecraft has a significant impact on the required deflection time.