Gravitational orbit-attitude coupling dynamics of a large solar power satellite

The gravitational coupling of the orbit and attitude motions of a large flexible solar power satellite (SPS) is studied in this paper. The orbital and attitude dynamical equations of a SPS with flexible vibration are firstly derived. Then, the gravitational force and torque are expanded to the fourth order of a Taylor series in the small size/orbital ratio. The gravitational forces and torques generated by the Sun, the Moon and the oblateness of the Earth are also investigated. The simulation examples are finally presented, and the results have demonstrated that the higher order gravitational force and torque of the Earth have great influences on the orbital motion and ground pointing precision of the SPS.