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Gravity gradient satellite stabilization and performance analyzed, using computer simulation of motion equations, including eddy current dampers, solar effect, orbital eccentricity, etc
Gravity gradient satellite stabilization and performance analyzed, using computer simulation of motion equations, including eddy current dampers, solar effect, orbital eccentricity, etc
Configuration selection for passive gravity gradient satellites
Three-body gravity gradient satellite orbital plane motion analysis, studying transient damping of proposed tethered orbiting interferometer /TOI/
Oscillation behavior of gravity gradient librations and flexural modes of cruciform satellite with single degree of freedom
Roll and attitude stability for gravity gradient satellites
Systems analysis and design of gravity gradient satellites using viscous coupling between earths magnetic and gravitational fields
Digital program for dynamics of nonrigid gravity gradient satellites
Time optimal control of gravity gradient satellites with disturbances
Applications technology satellite gravity gradient stabilization system
Stabilization system analysis and performance of GEOS-A gravity gradient satellite
Gravity gradient stabilization system for applications technology satellite
The use of active control for stability augmentation of passive gravity gradient satellites is investigated. The reaction jet method of control is the main interest. Satellite nonrigidity is emphasized. The reduction in the Hamiltonian H is used as a control criteria. The velocities, relative to local vertical, of the jets along their force axes are shown to be of fundamental significance. A basic control scheme which satisfies the H reduction criteria is developed. Each jet is fired when its velocity becomes appropriately large. The jet is de-energized when velocity reaches zero. Firing constraints to preclude orbit alteration may be needed. Control is continued until H has been minimized. This control policy is investigated using impulse and rectangular pulse models of the jet outputs.
Gravity gradient stabilization systems for Application Technology Satellites
Applications Technology Satellite gravity gradient stabilization systems status report
Equation providing nodal angle for largest roll libration with twice orbital frequency derived for gravity gradient satellite
Heat pipes with Freon working fluid applied to thermal control of transponders in low altitude gravity gradient satellite GEOS-B
The anomalous oscillatory behavior of three satellites was examined. The satellites were all hinged, two-body, gravity gradient configurations passively stabilized about their three principal axes by gravity gradient and damper torques. Two basic behavior patterns were observed. Either the satellites were stable with attitude perturbations less than + or - 5 deg or their behavior tended towards a low frequency rigid body oscillation dominated by large yaw motions and in some cases by yaw inversions. A causal relationship between sun angle and the character of satellite behavior was observed which appears to indicate that thermal distortion is a critical factor in a gravity gradient satellite's dynamic behavior. The behavior appeared to be futher modified by the existence of response frequencies that were higher than anticipated values.