Patent US2386745A successfully refreshed from Google Patents.
US4262861A
Expired / Lapsed
US
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Inertially decoupled strapdown system
Assignee: Kearfott Guidance and Navigation Corp
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Filing: 1978-10-16
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Granted: 1981-04-21
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Expires: 1998-10-16
Abstract
Abstract The invention comprises a novel strapdown gyro inertial system having a single degree of freedom between it and the vehicle upon which it is mounted. An angular transducer having a low friction bearing is mounted on the vehicle along the vehicle roll axis bearing and supports the strapdown gyros and accelerometers that are skewed with respect to the roll axis. The method of determining the total vehicle attitude employs the gyros so that the vehicle rate around each gyro axis is integrated and combined with the vehicle angular roll to obtain the total attitude. The inertial momentum of the sensor block, electrically enhanced or strictly dependent upon its mass, decouples high acceleration inputs along the free axis and thus reduces the dynamic rate sensing requirement along the free axis. Also the novel configuration of the sensors skewed with respect to the free axis, permits easy calibration of gyro scale factors and other inertial parameters which are characteristics of gyroscopes and accelerometers. The calibration is attainable in the factory or in the field.
Inventors
- 👤 Murray S. Goldstein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:56
CPC Classifications
G; G01; G01C; G01C21/00; G01C21/10; G01C21/12; G01C21/16; G01C21/166; G01C21/183
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
82 words
A strapdown gyro inertial system comprising: means for transporting said strapdown inertial system, means affixed to said transporting means and mounted along the roll axis thereof, means having angular rotation along said roll axis mounted to said fixed means, and gyro means skewedly mounted with respect to said roll axis on said means having angular rotation whereby said means having angular rotation provides angular readout to add to gyro output and provides a reference for calibration of said strapdown gyro inertial system.
Claim 2
Dependent Claim
82 words
A strapdown gyro inertial system comprising: means for transporting said strapdown inertial system, means affixed to said transporting means and mounted along the roll axis thereof, means having angular rotation along said roll axis mounted to said fixed means, and gyro means skewedly mounted with respect to said roll axis on said means having angular rotation whereby said means having angular rotation provides angular readout to add to gyro output and provides a reference for calibration of said strapdown gyro inertial system.
Claim 3
Dependent Claim
54 words
The strapdown gyro inertial system of claim 1 wherein said means having angular rotation along said roll axis comprises: an angular transducer having low friction bearing said angular transducer reducing the total angular rate which said gyro means must sense and reducing the total angular rate range which said gyro means must accurately sense.
Claim 4
Dependent Claim
73 words
The strapdown gyro inertial system of claim 2 wherein said gyro means comprises: strapdown gyros and accelerometers skewedly mounted on said angular transducer with respect to said roll axis so that each axis of said gyros sensor can sense rotation about said roll axis and so that said skewing further reduces the total roll angular rate sensed by the gyros whereby the dynamic measuring range of said strapdown gyro inertial is further reduced.
Claim 5
Dependent Claim
92 words
A strapdown gyro inertial system comprising: a vehicle supporting said gyro inertial system, an angular transducer mounted on said vehicle and having angular rotation along the roll axis of said vehicle, and strapdown gyros and accelerometers skewedly mounted on said angular transducer with respect to said roll axis so that each axis of said gyro sensor can sense rotation about said roll axis and so that said skewing further reduces the total roll angular rate sensed by said gyros whereby the dynamic measuring range of said strapdown gyro system is further reduced.
Claim 6
Dependent Claim
92 words
A strapdown gyro inertial system comprising: a vehicle supporting said gyro inertial system, an angular transducer mounted on said vehicle and having angular rotation along the roll axis of said vehicle, and strapdown gyros and accelerometers skewedly mounted on said angular transducer with respect to said roll axis so that each axis of said gyro sensor can sense rotation about said roll axis and so that said skewing further reduces the total roll angular rate sensed by said gyros whereby the dynamic measuring range of said strapdown gyro system is further reduced.
Claim 7
Dependent Claim
33 words
The strapdown gyro inertial system of claim 4 comprising: means for converting the measured roll angle signal from said angle transducer and the rate signals from said gyros and accelerometers into digital signals.
Claim 8
Dependent Claim
148 words
A strapdown gyro inertial system comprising: a vehicle supporting said gyro inertial system, an angular transducer mounted on said vehicle and having angular rotation along the roll axis of said vehicle, strapdown gyros and accelerometers skewedly mounted on said angular transducer with respect to the roll axis of said vehicle so that each axis of said gyro sensors can sense rotation about the roll axis and so that said skewing further reduces the total roll angular rate sensed by said gyros, whereby the dynamic measuring range of said strapdown gyro system is further reduced, means for converting the measured roll angle signal from said angle transducer and the rate signals from said gyros and accelerometers into digital signals, and means for providing a compensated roll output that is combined with the integrated rate output of said gyros so that said roll output is decoupled along said roll axis.
Claim 9
Dependent Claim
148 words
A strapdown gyro inertial system comprising: a vehicle supporting said gyro inertial system, an angular transducer mounted on said vehicle and having angular rotation along the roll axis of said vehicle, strapdown gyros and accelerometers skewedly mounted on said angular transducer with respect to the roll axis of said vehicle so that each axis of said gyro sensors can sense rotation about the roll axis and so that said skewing further reduces the total roll angular rate sensed by said gyros, whereby the dynamic measuring range of said strapdown gyro system is further reduced, means for converting the measured roll angle signal from said angle transducer and the rate signals from said gyros and accelerometers into digital signals, and means for providing a compensated roll output that is combined with the integrated rate output of said gyros so that said roll output is decoupled along said roll axis.
Claim 10
Dependent Claim
23 words
The strapdown gyro inertial system of claim 6 comprising: means for transforming the compensated acceleration signals from body coordinate to inertial coordinate signals.
Claim 11
Dependent Claim
21 words
The strapdown gyro inertial system of claim 7 comprising: means operative on said inertial coordinate signals for providing system velocity signals.
Claim 12
Dependent Claim
21 words
The strapdown gyro inertial system of claim 8 comprising: means operative on said velocity signals for providing system position output signals.
Claim 13
Dependent Claim
225 words
A strapdown gyro inertial system comprising: a vehicle supporting said gyro inertial system, an angular transducer mounted to said vehicle having angular rotation along the roll axis of said vehicle, a plurality of strapdown gyros each oriented along three approximately orthogonal axes skewedly mounted on said angular transducer with respect to said roll axis, a plurality of accelerometers each oriented along the three orthogonal axes of said gyros also skewedly mounted on said angular transducer with respect to said roll axis, a digital converter for converting the measured roll angle signal from said angle transducer and the rate signals from said gyros and accelerometers into digital signals, a differentiator and compensation network for providing a compensated roll output signal that is combined with the rate and integrated rate output of said gyros, a body transform matrix for transforming the compensated signals from body coordinates to inertial coordinate signals, a first computation and integration network for converting said inertial coordinate signals into system velocity, a second computation and integration network operative upon the output of said first computation and integration network for providing system position, whereby the pg,19 single degree of freedom provided by said angle transducer and said skewing further reduces the total roll angular rate sensed by the roll gyro resulting in the dynamic measuring range of said strapdown gyro inertial system being reduced.
Claim 14
Dependent Claim
225 words
A strapdown gyro inertial system comprising: a vehicle supporting said gyro inertial system, an angular transducer mounted to said vehicle having angular rotation along the roll axis of said vehicle, a plurality of strapdown gyros each oriented along three approximately orthogonal axes skewedly mounted on said angular transducer with respect to said roll axis, a plurality of accelerometers each oriented along the three orthogonal axes of said gyros also skewedly mounted on said angular transducer with respect to said roll axis, a digital converter for converting the measured roll angle signal from said angle transducer and the rate signals from said gyros and accelerometers into digital signals, a differentiator and compensation network for providing a compensated roll output signal that is combined with the rate and integrated rate output of said gyros, a body transform matrix for transforming the compensated signals from body coordinates to inertial coordinate signals, a first computation and integration network for converting said inertial coordinate signals into system velocity, a second computation and integration network operative upon the output of said first computation and integration network for providing system position, whereby the pg,19 single degree of freedom provided by said angle transducer and said skewing further reduces the total roll angular rate sensed by the roll gyro resulting in the dynamic measuring range of said strapdown gyro inertial system being reduced.
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) | 1984-04-20 | 1984-10-20 | 1985-04-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-04-20 | 1988-10-20 | 1989-04-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-04-20 | 1992-10-20 | 1993-04-21 | $7700.00 | Window Closed / Lapsed |