Underactuated translational control of a rigid spacecraft

In this paper we consider a spacecraft with one main thruster for translational control and reaction wheels for full attitude control. This is an underactuated control problem, which in this paper is solved using backstepping in order to couple the position tracking problem with the attitude. Assuming that the thrust is non-zero the nonlinear tracking control law is shown to be uniformly globally exponentially stable, and simulations validate these results.