Results 241 to 250 of about 688,541 (286)

Robust Digital Control of Drag-Free Satellites

IFAC Proceedings Volumes, 2003
Abstract A drag-free satellite is a small proof-mass (PM) shielded by a spacecraft cavity and moving only subject to gravitational forces. This can be accomplished by a drag-free control keeping the PM centered in the cavity and compensating the non-gravitational forces acting on the spacecraft. A constellation of drag-free satellites can be employed
CANUTO, Enrico, ANDREIS D.
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Stability of Gravity-Stabilized Drag-Free Satellites

AIAA Journal, 1971
In a drag-free satellite, the relative position sensor null point and the thrustor lines of action will not be coincident with the vehicle mass center. Thus, attitude motion is sensed by the translation control system. The resulting coupling between the attitude and translational motions can cause attitude instabilities in a gravity stabilized drag ...
Fleming, Alan W., DeBra, Daniel B.
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Embedded Model Control Application to Drag-Free and Satellite-to-Satellite Tracking

2006 14th Mediterranean Conference on Control and Automation, 2006
This paper describes the realization of a generic simulator for formation flying satellites, and the design and application of Embedded Model Control (EMC) to the spacecraft control, as potentially applicable to a constellation of drag-free satellites.
MASSOTTI, Luca, CANUTO, Enrico, SILVESTRIN P.   +2 more
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Attitude and Drag Control: An Application to the GOCE Satellite

2003
The Gravity held and steady-stale Ocean Circulation Explorer (GOCE) satellite, currently planned to be launched in the course of 2006, will require a precise drag compensation and a fine attitude control along the Local Orbiting Reference Frame (LORF) of a polar Sun-synchronous low orbit, allowing the Earth gravity field to be recovered with ...
CANUTO, Enrico, MARTELLA P, SECHI G.
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Experimental investigation of electric drag on satellites

AIAA Journal, 1964
Effect of interaction between satellite charge and ambient ions /electric drag/ on satellites, considering ionized surface collisions and plasma ...
EARL D. KNECHTEL, WILLIAM C. PITTS
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The Effect of Atmospheric Drag on the Orbit of an Arfificial Satellite

The Mathematical Gazette, 1969
The study of artificial satellites is today a subject of topical interest and naturally much work has been completed in the field of satellite orbits. Many aspects of this work involve the use of differential equations. Unfortunately very few of these may be solved by ordinary analytic techniques.
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Satellite Drag Perturbations in an Oblate Diurnal Atmosphere

AIAA Journal, 1975
Analytic expressions are derived that describe decay rates in period and eccentricity, and rotation in perigee argument for orbits of small eccentricity ...
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Drag-Free Satellite Control

2008
Scientific satellite missions trying to investigate questions regarding geodesy and fundamental physics have become increasingly dependent on ultra low disturbance environments. The precision demanded by the experiments has risen continuously as experimenters strive to deepen their understanding.
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New Satellite Drag Modeling Capabilities

44th AIAA Aerospace Sciences Meeting and Exhibit, 2006
This paper reviews the operational impacts of satellite drag, the historical and current capabilities, and requirements to deal with evo lving higher accuracy requirements. Modeling of satellite drag variations showed little improvement from the 1960’s to the late 1990’s. After three decades of essentially no quantitative progress, the problem is being
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Errata-Drag Coefficients for AstronomicalObservatory Satellites

Journal of Spacecraft and Rockets, 1975
The first several lines immediately after Eq. (9) should read as follows: " where ?, , £2» ^3 are direction cosines of the south galactic pole, expressed in earth equatorial coordinates. The corresponding geometry is shown in Fig. 5." The last sentence on p.
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