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US3935523A
Expired / Lapsed
US
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Non-minimum phase linear controller for hydraulic mechanisms
Assignee: Adaptronics Inc
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Filing: 1974-04-22
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Granted: 1976-01-27
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Expires: 1994-04-22
Abstract
Abstract The disclosure relates to a non-minimum phase linear controller which uses positive servomechanism rate feedback to control hydraulic mechanisms. The disclosure also relates to a controller comprising, in combination, a conventional linear controller and a non-minimum phase linear controller, the outputs of the combined controllers being weighted in a predetermined ratio to provide a single output control signal.
Inventors
- 👤 Dixon Cleveland
- 👤 Milford R. Derrick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:52
CPC Classifications
G; G05; G05B; G05B5/00; G05B5/01; G05D; G05D3/00; G05D3/12; G05D3/14; G05D3/1445
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
194 words
A control system employing positive rate feedback for controlling a plant where the positive feedback is indicated by a right half plane zero of the S-plane in a root-locus system analysis, wherein the predominant plant characteristics are described by a transfer function of the form ##EQU3## where K, δ, and ω n are either constant or vary only a small amount around nominal values, and where s is the Laplace operator, comprising a. means responsive to command plant response minus measured plant response to provide a plant error signal, b. means for providing a plant rate response signal, and c. control means for controlling said plant, said control means comprising: d. means responsive to said plant error signal to provide a signal indicative thereof multiplied by a positive constant, e. means responsive to said plant rate response signal to provide a signal indicative thereof multiplied by a positive constant, and f. means for summing the signal provided in (d) plus the signal provided in (e) to provide a control signal for said plant said plus defining a zero in the right half portion of the S-plane when analyzing the system by the root-locus method.
Claim 2
Dependent Claim
194 words
A control system employing positive rate feedback for controlling a plant where the positive feedback is indicated by a right half plane zero of the S-plane in a root-locus system analysis, wherein the predominant plant characteristics are described by a transfer function of the form ##EQU3## where K, δ, and ω n are either constant or vary only a small amount around nominal values, and where s is the Laplace operator, comprising a. means responsive to command plant response minus measured plant response to provide a plant error signal, b. means for providing a plant rate response signal, and c. control means for controlling said plant, said control means comprising: d. means responsive to said plant error signal to provide a signal indicative thereof multiplied by a positive constant, e. means responsive to said plant rate response signal to provide a signal indicative thereof multiplied by a positive constant, and f. means for summing the signal provided in (d) plus the signal provided in (e) to provide a control signal for said plant said plus defining a zero in the right half portion of the S-plane when analyzing the system by the root-locus method.
Claim 3
Dependent Claim
74 words
A control system as set forth in claim 1, futher including: a. a second control means providing a second control signal for said plant, b. means for multiplying said control signal and said second control signal by constants to provide a weighted control signal and a second weighted control signal, and c. means for summing said weighted control signal and said second weighted control signal to provide a total control signal to said plant.
Claim 4
Dependent Claim
42 words
A control system as set forth in claim 1 wherein the plant to be controlled is a servo-valve actuated hydraulic motor, wherein the plant response is measured by a position synchromechanism, and wherein the plant rate response is measured by a tachometer.
Claim 5
Dependent Claim
41 words
A control system as set forth in claim 2 wherein the plant to be controlled is a servo-valve actuated hydraulic motor, wherein the plant response is measured by a synchromechanism, and wherein the plant rate response is measured by a tachometer.
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) | 1979-01-26 | 1979-07-28 | 1980-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-26 | 1983-07-28 | 1984-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-26 | 1987-07-28 | 1988-01-27 | $7700.00 | Window Closed / Lapsed |