Synchronization of twin-gyro precession under cross-coupled adaptive feedforward control

Cross-coupled adaptive feedforward control represents an emerging approach to synchronizing the precession of twin gyros of control-moment-gyro (CMG) devices intended for use in the slewing maneuvers of space structures. The gyro control system features the integration of an adaptive controller and a feedforward controller for each gyro control axis. Then, two such control mechanisms are linked together by a coupling law, in which an error in either gyro axis can affect overall control loops so that the disturbed axis is rapidly recovered with the undisturbed axis for the synchronous precession. This adaptive synchronization problem is formulated and analyzed along with a twin-gyro CMG model, and the adaptation law is optimally designed through an optimization process in an attempt to minimize the synchronization errors from twin-gyro precession. Simulated-time histories of CMGdriven slewing maneuvers under the synchronization control are presented to show the effectiveness of the present approach.