Patent ID: 6076772
Filing Date: 2000-06-20
Classification: B64G

Abstract:
A method of controlling the attitude of a spacecraft which has a resonance at a resonant frequency, said method employing an over-determined torquing system of attitude-control structures which include momentum wheels that each rotate in accordance with a selectable, respective angular-velocity waveform, said method comprising the steps of;selecting a selected set from all sets of angular-velocity waveforms that substantially realize a commanded momentum vector in said spacecraft when applied to a corresponding set of said momentum wheels wherein none of the angular-velocity waveforms of said selected set dwell at said resonant frequency; andconforming the angular velocity of said corresponding set of momentum wheels to said selected set of angular-velocity waveforms to realize a spacecraft attitude that corresponds to said commanded momentum vector without exciting said resonance;wherein said selecting step includes the step of choosing said selected set to be a set in which angular-velocity waveforms define a time-changing rotational frequency at any time that their instantaneous rotational frequency substantially equals said resonant frequency.