Accession Number : ADP003386

Title :   Overcoming Unobservability in Three-Axis Stabilization of Satellites,

Corporate Author : AEROSPATIALE CANNES-LA-BOCCA (FRANCE)

Personal Author(s) : Passeron,L. ; Bozzo,C.

Report Date : JAN 1984

Pagination or Media Count : 21

Abstract : An optimal solution is provided to the problem of attitude estimation for a three-axis stabilized satellite devoid of yaw sensor and undergoing significant disturbing torques. Influence of such torques on expectable system performance is analysed via a geometric approach. Estimation of satellite attitude is demonstrated to be systematically impaired by an error resulting from the system's torque-induced unobservability. The said error is then explicitly assessed as a function of the disturbing torques. Furthermore, assuming a priori knowledge of the disturbing torque amplitudes, an optimal observability canonical form is derived. Optimal attitude estimation is finally provided, together with the expression of the relative, thus minimized, systematic error. (Author)

Descriptors :   *Attitude control systems, *Satellite attitude, *Space systems, Stabilization systems, Errors, Torque, Gyro stabilizers, Equations of motion

Distribution Statement : APPROVED FOR PUBLIC RELEASE