Quasi-optimal deceleration of rotations of an asymmetric body in resistive medium

A minimum-time problem on deceleration of rotations of a free rigid body affected by a small control torque with close but not identical coefficients is studied; such a problem can be considered as a quasi-optimal control problem. In addition, the rigid body is affected by a small deceleration viscous friction torque. The body is assumed to be dynamically asymmetric. A quasi-optimal feedback control for the deceleration of rotations of the rigid body is constructed, the optimal control time, and phase trajectories are found. The quasi-stationary trajectories are analyzed.