METHOD OF CONTROLLING SPACECRAFT MOTION ABOUT CENTRE OF MASS IN MAINTAINING ORIENTATION Russian patent published in 2011 - IPC B64G1/24 

FIELD: transport.

SUBSTANCE: invention relates to control over spacecraft motion and position and may be used for maintenance of its orientation. Proposed method comprises determining error angle and angular speed and applying control action around spacecraft centre of mass if said parametres exceed preset threshold values. If said parametres are smaller than threshold values, then angle of drift of angular speed integration on the interval with its maximum magnitude smaller than half-period of the angle variation inside its zone of insensitivity at threshold angular speed. Minimum magnitude of interval should exceed the period of elastic vibrations of spacecraft structure. Minimum control action is applied to spacecraft if drift angle on termination of said interval is not smaller than the first threshold value. Said value equals the increment of error angle at angular speed equal to its designed variation caused by applied control action. Also, control action is applied when drift angle reaches or exceeds second threshold value. The latter value is reduced relative to the first one by the magnitude defined by relation of angular speed threshold to its designed variation caused by applied minimum control action. Duration of said control action is determined from relation of mean angular speed of drift to designed magnitude of control acceleration about centre of mass of spacecraft. Sign of control action is always opposite the drift angle sing. Aforesaid interval terminated or control action applied, drift angle is reset to it to be determined again.

EFFECT: higher accuracy of spacecraft angular rotation about centre of mass at error angle and angular speed smaller than threshold values.