US4498036A
Expired / Lapsed
US
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Adaptive control system
Assignee: Pneumo Abex Corp
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Filing: 1983-08-15
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Granted: 1985-02-05
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Expires: 2003-08-15
Abstract
Abstract A method of adaptive control for use in a controlled system having an adjustable forward loop gain and a control system apparatus for carrying out the method are disclosed. The control system measures the value of a parameter which is to be controlled and generates an error signal by comparing the measured valve of the parameter with a desired valve. The error signal is squared and the time derivative of the squared error signal is obtained. The control system compares the length of time that the derivative so obtained has a positive value to the time it has a negative value to obtain a gain control signal, and applies the gain control signal to the forward loop gain. The gain control signal reduces the adjustable forward loop gain until a preselected margin of stability in the controlled system is obtained.
Inventors
- 👤 Robert M. Salemka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:41
CPC Classifications
B; B25; B25J; B25J9/00; B25J9/16; B25J9/1628; B25J9/163; G; G05; G05B; G05B13/00; G05B13/02; G05B13/0205; G05B13/024; G05B13/0245; G05B19/00; G05B19/02; G05B19/18; G05B19/19; G05B2219/00; G05B2219/30; G05B2219/39; G05B2219/39178; G05B2219/41; G05B2219/41163; G05B2219/41434; G05B2219/42; G05B2219/42237; G05B2219/45; G05B2219/45083
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
117 words
An adaptive control method for controlling a parameter of a process or mechanism comprising the steps of measuring the value of the parameter, comparing the measured value with a desired value to obtain an error signal, squaring the error signal, taking the time derivative of the error signal squared, comparing the length of time that the time derivative of the error signal squared has a positive value to the length of time the time derivative of the error signal squared has a negative value to obtain a gain control signal, applying the error signal to the system through an amplifier whose gain is controlled by said gain control signal to adjust the parameter desired to be controlled.
Claim 2
Dependent Claim
117 words
An adaptive control method for controlling a parameter of a process or mechanism comprising the steps of measuring the value of the parameter, comparing the measured value with a desired value to obtain an error signal, squaring the error signal, taking the time derivative of the error signal squared, comparing the length of time that the time derivative of the error signal squared has a positive value to the length of time the time derivative of the error signal squared has a negative value to obtain a gain control signal, applying the error signal to the system through an amplifier whose gain is controlled by said gain control signal to adjust the parameter desired to be controlled.
Claim 3
Dependent Claim
61 words
The method of claim 1 wherein said step of comparing the length of time the time derivative of the error signal squared is positive and the length of time it is negative includes the steps of triggering a pulse width modulation circuit with the time derivative of the error signal squared and integrating the output of the pulse width modulation circuit.
Claim 4
Dependent Claim
43 words
The method of claim 2 wherein said step of triggering the pulse width modulation circuit includes the steps of triggering the pulse width modulation circuit only when the absolute value of the time derivative of the error signal squared exceeds a predetermined value.
Claim 5
Dependent Claim
48 words
The method of claim 2 further including the steps of multiplying the length of time the time derivative of the error signal squared is positive by a preselected constant and comparing the result with the length of time said time derivative of said error signal squared is negative.
Claim 6
Dependent Claim
29 words
The method of claim 1 including the step of limiting the maximum and minimum gain of said amplifier control through which the error signal is applied to the system.
Claim 7
Dependent Claim
87 words
In a system having a process with a controlled parameter, an error signal representing the difference between the actual and desired values of the controlled parameter and a variable gain amplifier for applying the error signal to the process to alter the controlled parameter, the method of controlling the gain of said amplifier including varying the gain of said amplifier in response to the integral of a pulse width modulation circuit triggered by a changing sign of the time derivative of the square of the error signal.
Claim 8
Dependent Claim
87 words
In a system having a process with a controlled parameter, an error signal representing the difference between the actual and desired values of the controlled parameter and a variable gain amplifier for applying the error signal to the process to alter the controlled parameter, the method of controlling the gain of said amplifier including varying the gain of said amplifier in response to the integral of a pulse width modulation circuit triggered by a changing sign of the time derivative of the square of the error signal.
Claim 9
Dependent Claim
15 words
The method of claim 6 including limiting the maximum and minimum gain of said amplifier.
Claim 10
Dependent Claim
36 words
The method of claim 7 including multiplying the amplitude of the portion of the output of the pulse width modulation circuit which is positive by a selected factor to establish a desired margin of system stability.
Claim 11
Dependent Claim
39 words
The method of claim 8 including providing the pulse width modulation circuit with a dead band whereby said circuit does not respond until the absolute value of the time derivative of the error signal squared exceeds a selected value.
Claim 12
Dependent Claim
106 words
An adaptive control system for controlling a process having an input, a forward gain and an output, said adaptive control system including means for measuring the value of said output, means for comparing the value of said output with a desired value for said output to obtain an error signal, means for squaring said error signal, means for taking the time derivative of said squared error signal, means for computing the sum of the length of time said derivative is positive and the length of time said derivative is negative, and means for controlling said forward gain of said controlled process in response to said sum.
Claim 13
Dependent Claim
106 words
An adaptive control system for controlling a process having an input, a forward gain and an output, said adaptive control system including means for measuring the value of said output, means for comparing the value of said output with a desired value for said output to obtain an error signal, means for squaring said error signal, means for taking the time derivative of said squared error signal, means for computing the sum of the length of time said derivative is positive and the length of time said derivative is negative, and means for controlling said forward gain of said controlled process in response to said sum.
Claim 14
Dependent Claim
20 words
The adaptive control system of claim 10 wherein said means for computing the sum includes a pulse width modulation circuit.
Claim 15
Dependent Claim
22 words
The adaptive control system of claim 11 wherein said pulse width modulation circuit has two output states, one positive and one negative.
Claim 16
Dependent Claim
21 words
The adaptive control system of claim 12 wherein said pulse width modulation circuit is triggered by changing sign of said derivative.
Claim 17
Dependent Claim
24 words
The adaptive control system of claim 13 wherein said pulse width modulation circuit includes means for adjusting the ratio between said two output states.
Claim 18
Dependent Claim
37 words
The adaptive control system of claim 12 wherein said pulse width modulation circuit includes a deadband whereby said pulse width modulation circuit changes output states only when the absolute value of said derivative exceeds a predetermined value.
Claim 19
Dependent Claim
20 words
The adaptive control system of claim 10 including means for limiting the maximum and minimum values of said forward gain.
References Cited (Backward Citations)
US3241015A
Cited
US3283230A
Cited
US3504247A
Cited
US3759139A
Cited
US4064444A
Cited
US4257074A
Cited
US4369400A
Cited
US4355273A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-05 | 1988-08-06 | 1989-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-05 | 1992-08-06 | 1993-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-05 | 1996-08-06 | 1997-02-05 | $7700.00 | Window Closed / Lapsed |