Attitude control of underactuated spacecraft

In this paper ive consider the problem of maneuvering an axisymmetric space craft in the case that no torques about the symmetry axis can be exerted, f or example due to a thruster failure. Explicit control laws are derived whi ch steer such a spacecraft between states of pure spin between prescribed a ttitudes. These laws are found by minimizing a Cost junctional measuring th e suitably weighted overall angular velocities during the maneuver. In arri ving at the solution, differential geometric techniques in the theory of op timal control are used.