US3902686A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combined vertical and lateral identical location of accelerometer and force system
Assignee: United States Department of the Air Force
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Filing: 1973-10-17
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Granted: 1975-09-02
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Expires: 1993-10-17
Abstract
Abstract A structural mode control system having sensing elements to operate control force application devices, such as aerodynamic control vanes. The sensing elements are located at the control force application point.
Inventors
- 👤 John H Wykes
- 👤 Alva S Mori
- 👤 Harvey J Hoge
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 16:18
CPC Classifications
G; G05; G05D; G05D1/00; G05D1/0055; G05D1/0066
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
245 words
A structural mode control system for any type of flexible aircraft comprising in combination: a set of control vanes located on the nose of said aircraft, said control vanes being geometrically arranged on opposite sides of said aircraft nose, said control vane having a negative dihedral angle, sensing means to simultaneously obtain both vertical and lateral force signals, said sensing means being located at the control force application point, said sensing means providing vertical and lateral signals in response to said vertical and lateral acceleration signals, said sensing means comprising a normal accelerometer unit to obtain said vertical force signals, said normal accelerometer unit having a first normal accelerometer located at said control vane to provide a first normal acceleration signal, and a second normal accelerometer located near the center of gravity of said aircraft to provide a second normal acceleration signal, said first and second normal acceleration signals being combined to provide said vertical signal, and a lateral accelerometer unit to obtain said lateral force signals, said lateral accelerameter unit having a first lateral accelerometer located at said control vane to provide a first lateral acceleration signal, and a second lateral accelerometer located near the center of gravity of said aircraft to provide a second lateral acceleration signal, said first and second lateral acceleration signals being combined to provide said lateral signal, and control means responsive to said vertical and lateral signals to provide simultaneous separate control signals to each of said control vanes.
Claim 2
Dependent Claim
245 words
A structural mode control system for any type of flexible aircraft comprising in combination: a set of control vanes located on the nose of said aircraft, said control vanes being geometrically arranged on opposite sides of said aircraft nose, said control vane having a negative dihedral angle, sensing means to simultaneously obtain both vertical and lateral force signals, said sensing means being located at the control force application point, said sensing means providing vertical and lateral signals in response to said vertical and lateral acceleration signals, said sensing means comprising a normal accelerometer unit to obtain said vertical force signals, said normal accelerometer unit having a first normal accelerometer located at said control vane to provide a first normal acceleration signal, and a second normal accelerometer located near the center of gravity of said aircraft to provide a second normal acceleration signal, said first and second normal acceleration signals being combined to provide said vertical signal, and a lateral accelerometer unit to obtain said lateral force signals, said lateral accelerameter unit having a first lateral accelerometer located at said control vane to provide a first lateral acceleration signal, and a second lateral accelerometer located near the center of gravity of said aircraft to provide a second lateral acceleration signal, said first and second lateral acceleration signals being combined to provide said lateral signal, and control means responsive to said vertical and lateral signals to provide simultaneous separate control signals to each of said control vanes.
Claim 3
Dependent Claim
223 words
A structural mode control system as described in claim 1 wherein said control means comprises: first and second notch filters to receive said vertical and lateral signals respectively, said first and second notch filters being tuned to eliminate said first harmonic of said vertical and lateral signals. first and second dynamic pressure schedule units receiving said vertical and lateral signals and optimizing said vertical and lateral signals respectively for a range of flight conditions. first and second gain and shaping units to integrate said vertical and lateral signals to obtain vertical velocity and lateral velocity signals respectively first and second washout units to monitor said vertical velocity and lateral velocity signals respectively, said first and second washout units disengaging the vertical and lateral systems respectively for malfunctions, a first limiter unit to electronically limit said vertical velocity signal, said lateral velocity signal being changed in sign and applied to said first limiter unit, a second limiter unit to electronically limit said lateral velocity signal, said vertical velocity signal being changed in sign and being applied to said second limiter unit, a first actuator unit to receive said vertical velocity signal and to position one of said control vanes in response thereto, and a second actuator unit to receive said lateral velocity signal to position the other of said control vanes in response thereto.
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) | 1978-09-01 | 1979-03-03 | 1979-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-01 | 1983-03-03 | 1983-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-01 | 1987-03-03 | 1987-09-02 | $7700.00 | Window Closed / Lapsed |