ATTITUDE REORIENTATION CONTROL FOR LIQUID-FILLED SPACECRAFT WITH ONE KIND OF APPENDAGE

Attitude reorientation control by momentum transfer via Lyapunov stability theory for liquid-filled spacecraft with lightweight cantilever appendage is studied. The sloshing liquid is substituted by a viscous pendulum ball, and the cantilever appendage is substituted by several concentrated particals. Dynamics equations of the major rigid body, the pendulum ball, and the concentrated particles are derived through the theorem of moment of momentum and Lagrange equation. The feedback control law used a weighting coefficient related nearly with the angular acceleration of the wheel, which can be determined by the initial and final states of the system and the steady state time of attitude maneuver. A criterion guarantying to achieve attitude reorientation is attained by Lyapunov stability theorem. Numerical simulations indicate the validity of the control law. Sensitivity of residual nutation angle of the spacecraft is analyzed to the rotation angle of the appendage to the plane of the major rigid body, the relative height of the appendage to the center of mass of the system, the length of the appendage, the rigidity of the appendage, the mass of the appendage, the vibration damping of the appendage and the steady state time of the attitude maneuver.