US3731544A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Star tracker system
Assignee: Kearfott Guidance and Navigation Corp
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Filing: 1971-03-31
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Granted: 1973-05-08
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Expires: 1991-03-31
Abstract
Abstract In a star tracker system a two axis gyroscope is fixed to the stellar sensor with its spin axis aligned with the line of sight with the stellar sensor. The stellar sensor is mounted on an inertial platform by gimbals which are controlled in response to the output signals of the two axis gyroscope to maintain the line of sight of the stellar sensor aligned to an inertial reference frame. The line of sight of the stellar sensor is changed to a new position by torquing the gyroscope.
Inventors
- 👤 R Acker
- 👤 F Murphy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:38
CPC Classifications
G; G01; G01S; G01S3/00; G01S3/78; G01S3/782; G01S3/785; G01S3/786; G01S3/7867; Y; Y10; Y10T; Y10T74/00; Y10T74/12; Y10T74/1218
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
222 words
In combination with an inertial navigation system including a frame, a gimbal servo system mounted on said frame, an inertial platform mounted on said gimbal servo system, platform gyro means mounted on said inertial platform, a computer operatively connected to said platform gyro means, stellar sensing means operatively connected to said computer to sense a star position, a gyroscope fixed to said stellar sensing means and operatively connected to said computer, and gimbal means operatively connected to said computer and mounting said gyroscope and said stellar sensing means on said platform and responsive to the output of said gyroscope to maintain the line of sight of said stellar sensing means in a predetermined alignment with said gyroscope as said inertial platform pivots with respect to said gyroscope, wherein said gimbal means comprises first and second gimbals, and wherein said gimbal servo system includes third and fourth and fifth gimbals, said first gimbal rotatably mounting said stellar sensing means and said gyroscope on said second gimbal, said second gimbal being rotatably mounted on said third gimbal, said third gimbal being rotatably mounted on said fourth gimbal, said fourth gimbal being rotatably mounted on said fifth gimbal, said fifth gimbal being rotatably mounted on said frame, and torquing means responsive to the output of said gyroscope to control the angular positions of said gimbals.
Claim 2
Dependent Claim
222 words
In combination with an inertial navigation system including a frame, a gimbal servo system mounted on said frame, an inertial platform mounted on said gimbal servo system, platform gyro means mounted on said inertial platform, a computer operatively connected to said platform gyro means, stellar sensing means operatively connected to said computer to sense a star position, a gyroscope fixed to said stellar sensing means and operatively connected to said computer, and gimbal means operatively connected to said computer and mounting said gyroscope and said stellar sensing means on said platform and responsive to the output of said gyroscope to maintain the line of sight of said stellar sensing means in a predetermined alignment with said gyroscope as said inertial platform pivots with respect to said gyroscope, wherein said gimbal means comprises first and second gimbals, and wherein said gimbal servo system includes third and fourth and fifth gimbals, said first gimbal rotatably mounting said stellar sensing means and said gyroscope on said second gimbal, said second gimbal being rotatably mounted on said third gimbal, said third gimbal being rotatably mounted on said fourth gimbal, said fourth gimbal being rotatably mounted on said fifth gimbal, said fifth gimbal being rotatably mounted on said frame, and torquing means responsive to the output of said gyroscope to control the angular positions of said gimbals.
Claim 3
Dependent Claim
26 words
In a combination as recited in claim 1 wherein said gyroscope has its spin axis aligned with the line of sight of said stellar sensing means.
Claim 4
Dependent Claim
16 words
In a combination as recited in claim 1 wherein said gyroscope comprises a two axis gyroscope.
Claim 5
Dependent Claim
27 words
In a combination as recited in claim 3 wherein the spin axis of said gyroscope is aligned with the line of sight of said stellar sensing means.
Claim 6
Dependent Claim
87 words
In a combination as recited in claim 1 wherein said first and second and third and fourth and fifth gimbals respectively have first and second and third and fourth and fifth torquers and respectively have first and second and third and fourth and fifth angle transducers, said torquers and said angle transducers being operatively connected to said computer, said first and second angle transducers further comprising first and second encoders to produce output signals representing the changes in the angular positions of said first and second gimbals.
Claim 7
Dependent Claim
26 words
In a combination as recited in claim 5 wherein said first and second encoders produce output pulses at equal angular increments of rotation of said gimbals.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-07 | 1976-11-06 | 1977-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-07 | 1980-11-06 | 1981-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-07 | 1984-11-06 | 1985-05-08 | $7700.00 | Window Closed / Lapsed |