Nonlinear geometry control of spacecraft for halo orbit maintenance

An innovative method for halo orbit maintenance is proposed in this paper using continuous low thrust. The circular restricted three-body problem with Sun and Earth as the two primaries is considered. The equations of motion are derived and the location and stability of the collinear equilibrium point discussed. A nonlinear geometry control law is designed to enable a spacecraft to track desired nominal orbit near halo orbit of the LI libration point in the Sun-Earth system. The controller is designed such that the actual orbit tracks a nominal orbit with good accuracy. Numerical results employing this method demonstrate the potential of this method.