Accession Number : AD0693030

Title :   ATTITUDE PERFORMANCE OF THE GEOS-II GRAVITY-GRADIENT SPACECRAFT.

Descriptive Note : Technical memo.,

Corporate Author : JOHNS HOPKINS UNIV SILVER SPRING MD APPLIED PHYSICS LAB

Personal Author(s) : Whisnant,James M. ; Waszkiewicz,Phillip R. ; Pisacane,Vincent L.

Report Date : JAN 1969

Pagination or Media Count : 53

Abstract : The purpose of the report is to discuss the design analysis and flight performance of the attitude stabilization system of one of the Geodetic Earth Orbiting Satellites, GEOS-II. Geocentric stabilization is achieved in a completely passive manner by utilization of the gravity-gradient principle and a passive energy dissipator. The system analysis is accomplished through a digital solution of the equations of motion which describe the orientation of the spacecraft in orbit. Flight performance is obtained by an onboard attitude measuring system which determines the orientation of the satellite-sun line and magnetic field vector in the satellite reference system. A comparison of the theoretical and measured orientation of the spacecraft concludes the paper. (Author)

Descriptors :   (*SCIENTIFIC SATELLITES, *ATTITUDE CONTROL SYSTEMS), STABILIZATION SYSTEMS, GRAVITY, EXTENDABLE STRUCTURES, BOOMS(EQUIPMENT), MAGNETIC FIELDS, TRANSFORMATIONS(MATHEMATICS), EULER ANGLES, GEOMAGNETISM, DAMPING, LOW ORBIT TRAJECTORIES, THERMAL RADIATION, DISTORTION, SOLAR WIND

Subject Categories : Unmanned Spacecraft
      Spacecraft Trajectories and Reentry

Distribution Statement : APPROVED FOR PUBLIC RELEASE