Accession Number : AD0282775

Title :   SATELLITE INERTIA-WHEEL ATTITUDE CONTROL ON ELLIPTICAL ORBITS

Corporate Author : DOUGLAS AIRCRAFT CO INC SANTA MONICA CALIF

Personal Author(s) : ABZUG,M.J.

Report Date : AUG 1962

Pagination or Media Count : 1

Abstract : An investigation is made of the attitude-control characteristics of a satellite on an elliptical orbit itude-con rol system consists of hree iner ia wheels in a closed-loop arrangement. A two-part perturbation analysis of the system is made. First, a reference-motion solution is obt i ed. his i a particular solution of the no linear equations of motion in which body axes coincide with reference axes. Then, perturbations from the reference motio are analyzed. The reference- otion solution is used to minimize the peak inertia-wh l spee s incurred in follo ing onu iformly rotating ref re c o a ellip ical orbit. An unda p d oscillation of very long period that varies with position on orbit is found in the perturbation analysis. The existence of thi oscillation is verified in the solution of the complete equations of motion by numerical analysis. A comparison of the numerical results with perturbation theory predictio s show that the motions following realistic injection errors ar very little affected by no linearities in th equations of motion and coordi r formatio . ut or) D - * %! % +++Satellite in rtia-wh el attitude control o lliptical orbits, two-part p rturb tion a alysis, reference-motion solution.

Descriptors :   *CONTROL SYSTEMS, *SATELLITE ATTITUDE, EQUATIONS, MATHEMATICAL ANALYSIS, MOTION, NONLINEAR DIFFERENTIAL EQUATIONS, ORBITS, PERTURBATION THEORY, SATELLITES (ARTIFICIAL), STABILITY

Distribution Statement : APPROVED FOR PUBLIC RELEASE