On the orientation of a gyrostat using internal rotors

A control scheme is proposed to guarantee three axial orientations of a gyrostat. The gyrostat is controlled by the action generated by rotating internal rotors. The control problem is concerned with the exponential stability of equilibrium positions of the gyrostat using servo-control moments which are applied to the internal rotors. The non-linear control law is obtained from the conditions that ensure the exponential stability of the desired position. The general solution of the equations of the perturbed motion is obtained as a function of time.