Attitude control method and apparatus for spacecraft rotating about an axis fixed to the airframe

摘要

PCT No. PCT/EP92/02049 Sec. 371 Date Jun. 23, 1994 Sec. 102(e) Date Jun. 23, 1994 PCT Filed Sep. 4, 1992 PCT Pub. No. WO93/04921 PCT Pub. Date Mar. 18, 1993.This device is used for controlling the attitude of a spacecraft to be rotated about a body's axis of rotation. Actuators generate torques about the axis of rotation and two lateral axes. Angular velocity signals omega X, omega Y with respect to the lateral axes are in each case fed to first and second signal paths. The latter contain an integrator. Modulators, which each comprise a variable dead zone, supply control signals for the actuators. In order to limit the nutation amplitude to a constant value in a reliable manner, multiplication elements are provided in the first and second signal paths. The lateral-axis angular velocity signals omega X, omega Y or the angular position signals PHI , theta are acted upon by factors which are proportional to the rotation axis angular velocity signal omega Z or its square in the multiplication elements. Furthermore, the thresholds of the dead zones of the modulators are varied proportionally to omega Z2. A corresponding process for the attitude control is also described.