Patent US3567155A successfully refreshed from Google Patents.
US3567155A
Expired / Lapsed
US
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Gravity gradient attitude control system
Assignee: BENJAMIN G ZIMMERMAN
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Filing: 1968-12-20
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Granted: 1971-03-02
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Expires: 1988-12-20
Abstract
Abstract A system for controlling and stabilizing the attitude of an artificial earth satellite includes a gravity gradient member mounted in a gimbal arrangement to have 2* of freedom. The angular deviation of the gravity gradient member and the satellite relative to the local vertical and the spacecraft angle command input signal selectively drive a plurality of inertial momentum wheels, one for each of the three spacecraft axes, provided to dampen the gravity gradient member librations. The gravity gradient member is controlled so that the equilibrium position of the longitudinal axis thereof is maintained in alignment with the local vertical in response to signals indicative of the rate of change of movement thereof with respect to the remainder of the satellite and a signal indicative of the angular deviation of the satellite position from the angle command.
Inventors
- 👤 James A Gatlin
- 👤 Henry C Hoffman
- 👤 Henry W Price
- 👤 Benjamin G Zimmerman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:05
CPC Classifications
B; B64; B64G; B64G1/00; B64G1/22; B64G1/24; B64G1/34; B64G1/28; B64G1/285; B64G1/36
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
98 words
An attitude control system for an artificial earth satellite capsule comprising a gravity gradient member mounted on the capsule with 2* of freedom, means for driving said member so that the member is driven towards a local vertical, inertia means for damping torques applied to the capsule in response to librations of the gravity gradient member from the local vertical and the angular deviation of the capsule from the local vertical for combining indications of said deviations, and means responsive to the angular displacement of the gravity gradient member from the local vertical for driving the inertia means.
Claim 2
Dependent Claim
98 words
An attitude control system for an artificial earth satellite capsule comprising a gravity gradient member mounted on the capsule with 2* of freedom, means for driving said member so that the member is driven towards a local vertical, inertia means for damping torques applied to the capsule in response to librations of the gravity gradient member from the local vertical and the angular deviation of the capsule from the local vertical for combining indications of said deviations, and means responsive to the angular displacement of the gravity gradient member from the local vertical for driving the inertia means.
Claim 3
Dependent Claim
18 words
The system of claim 1 wherein said inertia driving means is responsive to the attitude of the capsule.
Claim 4
Dependent Claim
56 words
The system of claim 1 wherein said inertia driving means derives a first signal indicative of the angular displacement of the gravity gradient member relative to the capsule, and means for comparing said first signal with a second signal indicative of the desired angular displacement of the gravity gradient member from the axis of the capsule.
Claim 5
Dependent Claim
23 words
The system of claim 1 wherein said member driving means is responsive to the angular deviation of the capsule from the local vertical.
Claim 6
Dependent Claim
41 words
The system of claim 1 wherein said member driving means is responsive to the angular deviation of the capsule from the local vertical and the time rate of change of angular movement of the gravity gradient member relative to the capsule.
Claim 7
Dependent Claim
30 words
The system of claim 1 wherein said member driving means is responsive to the time rate of change of angular movement of the gravity gradient member relative to the capsule.
Claim 8
Dependent Claim
53 words
The system of claim 1 wherein said member driving means includes means for deriving a first signal indicative of the angular deviation of the capsule from the local vertical, and means for comparing the first signal with a second signal indicative of the desired angular displacement of the capsule from the local vertical.
Claim 9
Dependent Claim
84 words
The system of claim 1 wherein said inertia driving means derives a first signal indicative of the angular displacement of the gravity gradient member relative to the capsule, and means for comparing said first signal with a second signal indicative of the desired angular displacement of the gravity gradient member from the axis of the capsule; and said member driving means includes means for comparing the first signal with another signal indicative of the desired angular displacement of the capsule from the local vertical.
Claim 10
Independent Claim
194 words
A system for controlling the attitude of an artificial earth satellite capsule having roll, pitch and yaw axes, comprising a gravity gradient member mounted on the capsule so that it is free to pivot with respect to the roll and pitch axes, means for driving said member with respect to said roll and pitch axes so that the capsule is driven towards a commanded attitude and the member is driven towards a local vertical, three momentum wheels, a different one of said momentum wheels being mounted with the spin axis thereof parallel to a different one of the capsule axes, means responsive to both the angular deviation of the gravity gradient member from the local vertical and the capsule angular position relative to the local vertical in each of first and second planes respectively including the roll and yaw axes and the pitch and yaw axes for controlling the acceleration of the momentum wheels having spin axes 035671577 parallel to the roll and pitch axes, and means responsive to a signal indicative of the capsule yaw angle for controlling the acceleration of the momentum wheel having a spin axis parallel to the yaw axis.
Claim 11
Independent Claim
194 words
A system for controlling the attitude of an artificial earth satellite capsule having roll, pitch and yaw axes, comprising a gravity gradient member mounted on the capsule so that it is free to pivot with respect to the roll and pitch axes, means for driving said member with respect to said roll and pitch axes so that the capsule is driven towards a commanded attitude and the member is driven towards a local vertical, three momentum wheels, a different one of said momentum wheels being mounted with the spin axis thereof parallel to a different one of the capsule axes, means responsive to both the angular deviation of the gravity gradient member from the local vertical and the capsule angular position relative to the local vertical in each of first and second planes respectively including the roll and yaw axes and the pitch and yaw axes for controlling the acceleration of the momentum wheels having spin axes 035671577 parallel to the roll and pitch axes, and means responsive to a signal indicative of the capsule yaw angle for controlling the acceleration of the momentum wheel having a spin axis parallel to the yaw axis.
Claim 12
Dependent Claim
51 words
The system of claim 9 wherein said member driving means includes means for sensing the deviations of the capsule from the local vertical in said first and second planes, the devIations in the first and second planes driving the gravity gradient member with respect to the roll and pitch axes, respectively.
Claim 13
Dependent Claim
74 words
The system of claim 10 further including means for deriving command signals indicative of a desired deviation angle of the capsule from the local vertical in said first and second planes, said means for driving the member with respect to the roll and pitch axes being responsive to said command signals, said means for controlling the momentum wheels having spin axes parallel to the roll and pitch axes being responsive to said command signals.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-03-01 | 1974-08-31 | 1975-03-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-01 | 1978-08-31 | 1979-03-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-01 | 1982-08-31 | 1983-03-02 | $7700.00 | Window Closed / Lapsed |