Accession Number:

AD0267521

Title:

PASSIVE AERODYNAMIC ATTITUDE STABILIZATION OF NEAR EARTH SATELLITES. VOLUME I. LIBRATIONS DUE TO COMBINED AERODYNAMIC AND GRAVITATIONAL TORQUES

Descriptive Note:

Corporate Author:

NORTH AMERICAN AVIATION INC COLUMBUS OH

Personal Author(s):

Report Date:

1961-07-01

Pagination or Media Count:

163.0

Abstract:

The general equations governing the angular motion of a rigid satellite are investigated for the case where both gravitational and aerodynamic torques are included, and where the atmosphere is assumed to be spherically symmetric but rotating. For a non-spinning, axisymmetric satellite, the vehicle is characterized by 3 dimensionless aerodynamic parameters and one inertia parameter. A Fourier series expansion of the coefficients of the equations gives equations of the nonhomogeneous Hill type. The complete equations of motion are solved for a circular orbit. Atmospheric rotation induces a steady-state yawing motion preventing yaw equilibrium from being achieved for other than equatorial orbits. The effects of configuration and orbit parameters are examined. Gravity gradients generally will not dominate until altitudes of 300-400 mi are achieved. At lower altitudes small amounts of aerodynamic stability suffice to override the gravitational torques.

Subject Categories:

  • Spacecraft Trajectories and Reentry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE