Attitude stability analysis of a dual-spin spacecraft in halo orbits

The attitude stability of a dual-spin spacecraft in libration point orbits is investigated. The equations of rotational motion of a spacecraft in libration point orbits are provided. Considering the case of a rigid spacecraft located at a libration point, the rotation equations are simplified, and the stability conditions are determined and illustrated with figures. In the case of a spacecraft that occupies a halo orbit far from a libration point, a semi-analytical approach was proposed. By approaching the gravity gradient torque with a multi-segment series, the rotational motion of the spacecraft can be expressed as a series of three modes of motion, which can be used to explain the mechanism of attitude motion of a dual-spin spacecraft in libration point orbits. Numerical simulations show the validity of the semi-analytical approach.