Patent US2636460A successfully refreshed from Google Patents.
US4032759A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Shipboard reference for an aircraft navigation system
Assignee: Kearfott Guidance and Navigation Corp
•
Filing: 1975-10-24
•
Granted: 1977-06-28
•
Expires: 1995-10-24
Abstract
Abstract A low cost shipboard reference system for carrying out the rapid alignment of aircraft inertial platforms in which an aircraft quality inertial reference is installed on shipboard and is operated in conjunction with a shipboard Kalman filter providing updating information thereto with the update connection from the Kalman to the shipboard inertial system normally kept opened and always kept opened during aircraft platform alignment to result in reference outputs for use in the aircraft system which are free of correlated noise but of sufficient accuracy for rapid alignment with a small azimuth error.
Inventors
- 👤 Boris Danik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:44
CPC Classifications
G; G01; G01C; G01C25/00; G01C25/005
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
162 words
A method of rapidly aligning aircraft inertial platforms installed in aircraft located aboard an aircraft carrier which changes its location with time, said aircraft carrier thereby having a state vector containing as elements at least the velocity of said aircraft carrier and its position, comprising the steps of: (a) installing a low-accuracy aircraft type inertial reference system on the aircraft carrier, said system including an inertial subsystem and a Kalman filter, said inertial subsystem providing as outputs quantities representing the velocity of the aircraft carrier, (b) installing means on the aircraft carrier providing updating information regarding the state vector of the aircraft carrier to said Kalman filter; (c) providing as a velocity reference to the aircraft the velocity outputs of the inertial subsystem of said inertial reference system; (d) updating said inertial subsystem of said inertial reference system from said Kalman filter at intervals of the order of magnitude of two hours and never while providing a velocity reference to an aircraft.
Claim 2
Independent Claim
162 words
A method of rapidly aligning aircraft inertial platforms installed in aircraft located aboard an aircraft carrier which changes its location with time, said aircraft carrier thereby having a state vector containing as elements at least the velocity of said aircraft carrier and its position, comprising the steps of: (a) installing a low-accuracy aircraft type inertial reference system on the aircraft carrier, said system including an inertial subsystem and a Kalman filter, said inertial subsystem providing as outputs quantities representing the velocity of the aircraft carrier, (b) installing means on the aircraft carrier providing updating information regarding the state vector of the aircraft carrier to said Kalman filter; (c) providing as a velocity reference to the aircraft the velocity outputs of the inertial subsystem of said inertial reference system; (d) updating said inertial subsystem of said inertial reference system from said Kalman filter at intervals of the order of magnitude of two hours and never while providing a velocity reference to an aircraft.
Claim 3
Dependent Claim
18 words
The method according to claim 1 wherein said Kalman filter is updated using outputs of an electro-magnetic log.
Claim 4
Dependent Claim
18 words
The method according to claim 1 wherein said Kalman filter is updated using an electronic position indicating device.
Claim 5
Dependent Claim
16 words
The method according to claim 3 wherein said Kalman filter is updated using a Loran set.
Claim 6
Dependent Claim
162 words
Apparatus for rapidly aligning an aircraft inertial platform installed in an aircraft which is aboard a moving vehicle, said vehicle thereby having a state vector which includes at least components of velocity and position, comprising: (a) a low accuracy aircraft type inertial reference system installed on the vehicle, said system including an inertial subsystem and a Kalman filter, said inertial subsystem providing velocity outputs; (b) means installed on the vehicle coupled as inputs to said Kalman filter of said inertial reference system for providing updating information relating to the state vector of the vehicle; (c) means for coupling the velocity outputs of said inertial subsystem of said inertial reference system to the aircraft inertial platform of the aircraft to provide a velocity reference thereto; and (d) means coupling the outputs of said Kalman filter to said inertial subsystem including means for selectively opening and closing the connection therebetween to permit updating at infrequent intervals on the order of magnitude of two hours.
Claim 7
Dependent Claim
162 words
Apparatus for rapidly aligning an aircraft inertial platform installed in an aircraft which is aboard a moving vehicle, said vehicle thereby having a state vector which includes at least components of velocity and position, comprising: (a) a low accuracy aircraft type inertial reference system installed on the vehicle, said system including an inertial subsystem and a Kalman filter, said inertial subsystem providing velocity outputs; (b) means installed on the vehicle coupled as inputs to said Kalman filter of said inertial reference system for providing updating information relating to the state vector of the vehicle; (c) means for coupling the velocity outputs of said inertial subsystem of said inertial reference system to the aircraft inertial platform of the aircraft to provide a velocity reference thereto; and (d) means coupling the outputs of said Kalman filter to said inertial subsystem including means for selectively opening and closing the connection therebetween to permit updating at infrequent intervals on the order of magnitude of two hours.
Claim 8
Dependent Claim
17 words
Apparatus according to claim 5 wherein said means for providing state vector information comprises an electronic log.
Claim 9
Dependent Claim
18 words
Apparatus according to claim 5 wherein said means for providing state vector information comprises electronic position indicating means.
Claim 10
Dependent Claim
14 words
Apparatus according to claim 7 wherein said position indicating means comprises a Loran set.
Claim 11
Dependent Claim
14 words
Apparatus according to claim 5 wherein said Kalman filter comprises a programmed digital computer.
Claim 12
Dependent Claim
12 words
Apparatus according to claim 5 wherein said vehicle is an aircraft carrier.
References Cited (Backward Citations)
US2914763A
Cited
US3345017A
Cited
US3576124A
Cited
US3702477A
Cited
US3790766A
Cited
US3872284A
Cited
US3903398A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-06-27 | 1980-12-27 | 1981-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-27 | 1984-12-27 | 1985-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-27 | 1988-12-27 | 1989-06-28 | $7700.00 | Window Closed / Lapsed |