US3749914A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vehicle attitude sensor
Assignee: United States Department of the Air Force
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Filing: 1970-12-21
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Granted: 1973-07-31
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Expires: 1990-12-21
Abstract
Abstract An apparatus to control the alignment of the spin axis of a communications satellite with the major axis of an eccentric, near polar orbit. The on-board prediction of the time of apogee passage and autonomous control at apogee for the spin axis alignment with the local vertical is also provided. Thus, cumulative errors in the apogee epoch predictions due to orbital period errors are avoided.
Inventors
- 👤 R Terasaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 03:11
CPC Classifications
B; B64; B64G; B64G1/00; B64G1/22; B64G1/24; B64G1/36; B64G1/363; B64G1/244; B64G1/365
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
287 words
A vehicle attitude sensor apparatus comprising in combination: a means for sensing direction, said sensing means providing a pair of repetitve pulse signals, said pair of repetitive pulse signals being a first pulse train and a second pulse train, a frequency oscillator for generating pulses with a repetitive frequency greater than said pair of repetitive pulse signals, a first counter connected to said frequency oscillator, said first counter receiving said pulse from said frequency oscillator, said first counter receiving said pair of repetitive pulse signals, a first flip flop unit receiving said pulses from said frequency oscillator, said first flip flop providing an output signal, a second flip flop unit receiving said pair of repetitive pulse signals from said sensing means, said second flip flop providing an output signal, a third flip flop unit receiving said first pulse train, said third flip flop providing an output signal, an and gate having a first and second input, said and gate receiving said output signal from said first flip flop at said first input, said receiving said output signal from said second flip flop at said second input, said and gate providing an output signal, a second counter connected to said and gate to receive said output signal from said and gate, said second counter receiving said output signal from said third flip flop, said second counter providing an output signal, a comparator receiving said output signals from said first and second counTers, said comparator comparing said output signals and providing an output signal, and, a one shot multivibrator receiving said output signal from said comparator, said multivibrator providing an output signal to said third flip flop, said output signal being the phase control pulse for said vehicle attitude.
Claim 2
Dependent Claim
287 words
A vehicle attitude sensor apparatus comprising in combination: a means for sensing direction, said sensing means providing a pair of repetitve pulse signals, said pair of repetitive pulse signals being a first pulse train and a second pulse train, a frequency oscillator for generating pulses with a repetitive frequency greater than said pair of repetitive pulse signals, a first counter connected to said frequency oscillator, said first counter receiving said pulse from said frequency oscillator, said first counter receiving said pair of repetitive pulse signals, a first flip flop unit receiving said pulses from said frequency oscillator, said first flip flop providing an output signal, a second flip flop unit receiving said pair of repetitive pulse signals from said sensing means, said second flip flop providing an output signal, a third flip flop unit receiving said first pulse train, said third flip flop providing an output signal, an and gate having a first and second input, said and gate receiving said output signal from said first flip flop at said first input, said receiving said output signal from said second flip flop at said second input, said and gate providing an output signal, a second counter connected to said and gate to receive said output signal from said and gate, said second counter receiving said output signal from said third flip flop, said second counter providing an output signal, a comparator receiving said output signals from said first and second counTers, said comparator comparing said output signals and providing an output signal, and, a one shot multivibrator receiving said output signal from said comparator, said multivibrator providing an output signal to said third flip flop, said output signal being the phase control pulse for said vehicle attitude.
Claim 3
Dependent Claim
63 words
A vehicle attitude sensor apparatus as described in claim 1 wherein said direction sensing means comprises: a sun sensor unit to sense the angle between the vehicle spin axis and the sun direction, said sun sensor providing an electronic pulse signal, said sun sensor being mounted on an xz plane said pulse signal indicating coincidence of the sun direction with said xz plane.
Claim 4
Dependent Claim
85 words
A vehicle attitude sensor apparatus as described in claim 1 wherein said direction sensing means comprises: an apogee earth sensor, said apogee earth sensor is mounted on said vehicle at an angle, said angle is canted with respect to the spin axis of said vehicle, said apogee earth sensor providing an output signal, and, a normal earth sensor being aligned orthogonally to said spin axis, said normal earth sensor scanning a plane normal to said spin axis, said normal earth sensor providing an output signal.
References Cited (Backward Citations)
US3427453A
Cited
US3512085A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-30 | 1977-01-29 | 1977-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-30 | 1981-01-29 | 1981-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-30 | 1985-01-29 | 1985-07-31 | $7700.00 | Window Closed / Lapsed |