Smooth rapid three-axis reorientation of spacecraft

A practical chattering-free near-minimum-time control law is proposed to rotate a spacecraft around its eigenaxis. In the proposed control law, an analytic reference attitude generation method for smooth rapid three-axis reorientation along its eigenaxis is proposed first. Practical control constraints such as wheel torque and wheel speed are also taken into account in the reference attitude generation method. Attitude tracking feedback control is then used during the eigenaxis rotations to deal with inertia uncertainty and external disturbances. Simulation results demonstrate the effectiveness of the proposed control scheme.