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US6882889B2 Expired / Lapsed US ⏱️ 0.0 years remaining

Constrained dynamic inversion control algorithm

Assignee: RTX Corp
•
Filing: 2002-12-02
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Granted: 2005-04-19
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Expires: 2022-12-02
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Abstract

Abstract A method of controlling a multivariable system includes the step of receiving a plurality of sensor signals indicating current conditions of the system and receiving a plurality of commands. The desired dynamic response of the system is then determined based upon the commands and the sensor signals. The problem of controlling the system to achieve the desired dynamic response without violating numerous actuator and physical constraints is then formulated as a quadratic programming problem. By solving the quadratic programming problem, the effector commands are determined and the physical constraints are enforced.

Inventors

  • 👤 James W. Fuller
  • 👤 Indraneel Das

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 20:41
CPC Classifications
G; G05; G05B; G05B13/00; G05B13/02; G05B13/04; G05B13/042

Claims Analysis

Total Claims: 30
Claim 1
Independent Claim 94 words
A method for controlling a multivariable system including the steps of: a) receiving a plurality of sensor signals indicating current conditions of the system which are periodically sampled; b) receiving a plurality of commands; c) determining a desired change in output of the system for at least one future controller sample based upon the commands and sensor signals; d) formulating the problem of determining actuator commands to achieve the change in output by the at least one future controller sample as a quadratic programming problem that includes physical limits or constraints of the system.
Claim 2
Independent Claim 94 words
A method for controlling a multivariable system including the steps of: a) receiving a plurality of sensor signals indicating current conditions of the system which are periodically sampled; b) receiving a plurality of commands; c) determining a desired change in output of the system for at least one future controller sample based upon the commands and sensor signals; d) formulating the problem of determining actuator commands to achieve the change in output by the at least one future controller sample as a quadratic programming problem that includes physical limits or constraints of the system.
Claim 3
Dependent Claim 48 words
The method of claim 1 wherein said step c) further includes the steps of i) determining how a nominal system output should change in the at least one future controller sample, ii) specifying the physical limits or constraints, and iii) determining the actuator commands to achieve the change.
Claim 4
Dependent Claim 54 words
The method of claim 1 further including the step of formulating the problem into a part that determines how a nominal system output should change in the at least one future controller sample, a part that determines the physical limits and constraints, and a part that determines the actuator commands to achieve this change.
Claim 5
Dependent Claim 46 words
The method of claim 3 wherein the change requested for the at least one future controller sample is specified in terms of the next output value, a rate of change of the output, acceleration of the output, or net generalized forces and moments on the system.
Claim 6
Dependent Claim 51 words
The method of claim 3 wherein the part determining the change in system output required in the at least one future controller sample, in order to achieve a desired command response trajectory, is accomplished using feedback control, feedforward control, explicit use of a model of the desired response or neural networks.
Claim 7
Dependent Claim 12 words
The method of claim 1 where the physical constraints are directly included.
Claim 8
Dependent Claim 22 words
The method of claim 1 where the physical constraints are indirectly included in terms of the fastest approach to the limit allowed.
Claim 9
Dependent Claim 28 words
The method of claim 1 further including the step of: e) solving the quadratic programming problem to determine effector commands that will cause the desired change in output.
Claim 10
Dependent Claim 15 words
The method of claim 8 wherein the desired dynamic response includes a plurality of outputs.
Claim 11
Dependent Claim 23 words
The method of claim 9 wherein the multivariable system is cross-coupled, such that each of the effector commands affects each of the outputs.
Claim 12
Dependent Claim 13 words
The method of claim 10 further including the step of enforcing effector limits.
Claim 13
Dependent Claim 26 words
The method of claim 11 further including the step of enforcing a prioritization of the commands and physical limits, when not all commands can be accomplished.
Claim 14
Dependent Claim 34 words
The method of claim 12 wherein the step of enforcing a prioritization further including the step of turning off feedback control integrators associated with lower priority outputs, if all outputs can not be achieved.
Claim 15
Dependent Claim 28 words
The method of claim 13 wherein the step of enforcing a prioritization further includes setting higher performance index weights on the desired change of the higher priority outputs.
Claim 16
Dependent Claim 24 words
The method of claim 14 further including the step of changing a weighting on each of a plurality of the commands and physical limits.
Claim 17
Dependent Claim 128 words
A multivariable control system comprising: a plurality of sensors sampling current conditions of the system including a system output in a plurality of sample periods; a plurality of effectors for changing dynamics of the system in response to effector commands; a dynamic feed forward module determining a desired change in system output for a subsequent one of the plurality of sample periods; a dynamic model follower comparing the desired change in system output with the system output to adjust an output change command as needed; and a dynamic inversion module determining the effector commands in order to change the system output based upon the determination by the dynamic feed forward and dynamic model follower modules by formulating a quadratic programming problem to include physical limits of the system.
Claim 18
Dependent Claim 128 words
A multivariable control system comprising: a plurality of sensors sampling current conditions of the system including a system output in a plurality of sample periods; a plurality of effectors for changing dynamics of the system in response to effector commands; a dynamic feed forward module determining a desired change in system output for a subsequent one of the plurality of sample periods; a dynamic model follower comparing the desired change in system output with the system output to adjust an output change command as needed; and a dynamic inversion module determining the effector commands in order to change the system output based upon the determination by the dynamic feed forward and dynamic model follower modules by formulating a quadratic programming problem to include physical limits of the system.
Claim 19
Dependent Claim 39 words
The multivariable control system of claim 16 wherein the dynamic inversion module includes a constraint formation module for transforming the physical limits of the system into a form of linear inequality equations with the effector commands as independent variables.
Claim 20
Dependent Claim 23 words
The multivariable system of claim 17 where the linear inequality equations express the fastest dynamic trajectory with which the limits can be approached.
Claim 21
Dependent Claim 30 words
The multivariable system of claim 16 wherein the dynamic inversion module further includes a performance index formation module formulating the effector commands as a solution of the quadratic programming problem.
Claim 22
Dependent Claim 27 words
The multivariable system of claim 19 wherein the dynamic inversion block further includes a quadratic programming block for solving the quadratic optimization problem and linear equality equations.
Claim 23
Dependent Claim 96 words
A computer readable medium storing a computer program, which when executed by a computer performs the steps of: a) receiving a plurality of sensor signals indicating current conditions of the system which are periodically sampled; b) receiving a plurality of commands; c) determining a desired change in output of the system for a next controller sample based upon the commands and sensor signals; d) formulating the problem of determining actuator commands to achieve the change in output by the next controller sample as a quadratic programming problem that includes physical limits or constraints of the system.
Claim 24
Dependent Claim 96 words
A computer readable medium storing a computer program, which when executed by a computer performs the steps of: a) receiving a plurality of sensor signals indicating current conditions of the system which are periodically sampled; b) receiving a plurality of commands; c) determining a desired change in output of the system for a next controller sample based upon the commands and sensor signals; d) formulating the problem of determining actuator commands to achieve the change in output by the next controller sample as a quadratic programming problem that includes physical limits or constraints of the system.
Claim 25
Dependent Claim 27 words
The computer readable medium of claim 21 which when executed by a computer further performs the steps of solving the quadratic programming problem to determine effector commands.
Claim 26
Dependent Claim 17 words
The computer readable medium of claim 22 wherein the desired dynamic response includes a plurality of outputs.
Claim 27
Dependent Claim 25 words
The computer readable medium of claim 23 wherein the multivariable system is cross-coupled, such that each of the effector commands affects each of the outputs.
Claim 28
Dependent Claim 15 words
The computer readable medium of claim 24 further performing the step of enforcing effector limits.
Claim 29
Dependent Claim 18 words
The computer readable medium of claim 25 further performing the step of prioritizing the commands and physical limits.
Claim 30
Dependent Claim 26 words
The computer readable medium of claim 26 further performing the step of changing a weighting on each of a plurality of the commands and physical limits.

References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2008-04-18 2008-10-18 2009-04-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2012-04-18 2012-10-18 2013-04-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2016-04-18 2016-10-18 2017-04-19 $7700.00 Window Closed / Lapsed

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