초록 ▼

An active nutation control system for a space vehicle spinning about a geometric axis has thrusters for creating an external torque about an axis transverse to the first. The amplitude of the nutation and its phase in relation with the spinning movement are detected. A control arrangement receives s

An active nutation control system for a space vehicle spinning about a geometric axis has thrusters for creating an external torque about an axis transverse to the first. The amplitude of the nutation and its phase in relation with the spinning movement are detected. A control arrangement receives signals from the nutation detectors, computes the changes in the angular direction of the angular momentum of the vehicle caused by thruster activation and energizes the thrusters when contemporaneously the amplitude of the nutation movement is greater than a predetermined threshold, the phase corresponds to maximum efficiency of said thrusters in reducing nutation momentum of the vehicle or at least does not increase it.

대표청구항 ▼

An active nutation control system for a space vehicle spinning about one of its geometrical axes, having: means for creating pulses of external rocking torque about an axis transverse to said geometrical axis; means carried by said space vehicle for delivering a periodically varying signal having an

An active nutation control system for a space vehicle spinning about one of its geometrical axes, having: means for creating pulses of external rocking torque about an axis transverse to said geometrical axis; means carried by said space vehicle for delivering a periodically varying signal having an amplitude representative of the magnitude of the nutation of said space vehicle and a frequency equal to the nutation frequency of said space vehicle; and control means for controlling the torque-creating means, comprising: first enabling means to deliver a signal authorizing actuation of said torque creating means for delivering a pulse of predetermined time duration at times having a predetermined phase difference with respect to said periodically varying signal; second enabling means to compare said periodically varying signal with a predetermined threshold and to deliver a signal when the amplitude of said signal exceeds said threshold; third enabling means connected to receive signals representative of the pulses to be delivered by said torque-creating means for computing the cumulative change in the direction of the angular momentum of the space vehicle due to the actuation of said torque-creating means and to deliver a signal under conditions where the next pulse does not increase the angular discrepancy between the current direction of the angular momentum of the vehicle and the initial direction thereof; and means responsive to the signals from said first, second and third means for causing delivery of one of said pulses upon simultaneous occurrences of all three signals.