MODEL-BASED SYSTEM CALIBRATION FOR CONTROL SYSTEMS

• US 20100125347A1
• Filed: 11/19/2008
• Published: 05/20/2010
• Est. Priority Date: 11/19/2008
• Status: Abandoned Application

• Current Assignee: Harris Corporation (L3Harris Technologies, Inc.)
• Original Assignee: Harris Corporation (L3Harris Technologies, Inc.)
• Inventors: Minear, Kathleen, Martin, G. Patrick, Adams, William C. JR.
• Application Number:
  US12/274,011
• Publication Number:
  US 20100125347A1
• Time in Patent Office: Days
• US Class Current: 700/31
• CPC Class Codes: G05B 13/044 not using a perturbation signal

Abstract

A system and method for model-based control of a the physical system, based on a computer simulation model approximating operating characteristics of at least a portion of the plurality of components and having one or more model parameters for adjusting a modeled operating characteristic of at least one of the plurality of components is provided. In the system and method at least one active input parameter for the physical system is generated based on current values for the model parameters and the computer simulation model and at least one measured system parameter value and at least one modeled system parameter value are obtained for measuring the performance of physical system responding to the active input parameter. The system and method also evaluate a difference between the measured system parameter value and the modeled system parameter value and update the current values for the model parameters to minimize the difference.

Claims

1. A method of using a model-based control system to control a physical system having a plurality of components, said model-based control system based on a computer simulation model of said physical system, said computer simulation model approximating operating characteristics of at least a portion of said plurality of components, said computer simulation model having one or more model parameters for adjusting a modeled operating characteristic of at least one of said plurality of components, the method comprising:

generating at least one active input parameter for said physical system based on current values for said model parameters and said computer simulation model;

obtaining at least one measured system parameter value and at least one modeled system parameter value for measuring the performance of physical system responding to said active input parameter;

evaluating a difference between said measured system parameter value and said modeled system parameter value; and

updating said current values for said model parameters to minimize said difference.

2. The method of claim 1, wherein said updating further comprises updating at least said current values for said model parameters associated with said measured system parameter value.

3. The method of claim 1, wherein said obtaining said measured system parameter value comprises:

measuring at least one output signal of said one of said plurality of components responsive to said active input parameter;

calculating said measured system parameter value based on said output signal.

4. The method of claim 3, wherein said obtaining said estimated parameter value comprises:

estimating said output signal using a computer simulation of said system, said computer simulation based at least on said computer simulation model, said current values for said model parameters, and said active input parameter;

calculating said modeled system parameter value based on said output signal estimated using said computer simulation.

5. The method of claim 4, wherein said computer simulation during said estimating said output signal is further based on at least one passive input parameter.

6. The method of claim 5, wherein said passive input parameter is at least one among a mechanical, a chemical, or an electromagnetic measurement performed in or around said physical system.

7. The method of claim 1, wherein said updating further comprises:

estimating one or more new values for at least one of said model components;

recomputing said difference for said new values; and

altering said current values for said model components based on a one of said new values minimizing said difference after said recomputing.

8. The method of claim 7, wherein said estimating, said recomputing and said altering are performed iteratively.

9. The method of claim 8, wherein said estimating said new values is based on a steepest descent algorithm.

10. A model-based control system for controlling a physical system having a plurality of components, the control system comprising:

a storage element for receiving a computer simulation model of said physical system, said computer simulation model approximating operating characteristics of at least a portion of said plurality of components, said computer simulation model having one or more model parameters for adjusting a modeled operating characteristic of at least one of said plurality of components; and

a processing element for generating at least one active input parameter for physical system based on current values for said model parameters and said computer simulation model, said processing element further comprising a model-based calibration element for adjusting said current values for said model parameters based on a response of said physical system to said active input parameter,

wherein said adjusting comprises obtaining at least one measured system parameter value and at least one modeled system parameter value for measuring said response of said physical system, evaluating a difference between said measured system parameter value and said modeled system parameter value, and updating said current values for said model parameters to minimize said difference.

11. The system of claim 10, wherein said processing element is further configured during said updating for updating at least said current values for said model parameters associated with said measured system parameter value.

12. The system of claim 10, wherein said model-based calibration element is configured during said obtaining said measured system parameter value for:

measuring at least one output signal of said one of said plurality of components responsive to said active input parameter;

calculating said measured system parameter value based on said output signal.

13. The system of claim 12, wherein said model-based calibration element is configured during said obtaining said estimated parameter value for:

estimating said output signal using a computer simulation of said system, said computer simulation based at least on said computer simulation model, said current values for said model parameters, and said active input parameter;

calculating said modeled system parameter value based on said output signal estimated using said computer simulation.

14. The system of claim 13, wherein said computer simulation in said model-based calibration element is further based on at least one passive input parameter.

15. The system of claim 14, wherein said passive input parameter is at least one among a mechanical, a chemical, or an electromagnetic measurement performed in or around said physical system.

16. The system of claim 10, wherein said model-based calibration element is configured during said updating for:

estimating one or more new values for at least one of said model components;

recomputing said difference for said new values; and

altering said current values for said model components based on a one of said new values minimizing said difference after said recomputing.

17. The system of claim 16, wherein said model-based calibration element performs said estimating, said recomputing and said altering iteratively.

18. The system of claim 17, wherein said estimating said new values is based on a steepest descent algorithm.

19. A communications system, comprising:

an array of antenna elements; and

a control system communicatively coupled to said array and generating control signals for said array, wherein said control system comprises;

a storage element for receiving a computer simulation model of said communications system, said computer simulation model approximating operating characteristics of said array of antenna elements, said computer simulation model having one or more model parameters for adjusting a modeled operating characteristic of said array of antenna elements; and

a processing element for generating said control signals for said array of antenna element based on current values for said model parameters and said computer simulation model, said processing element further comprising a model-based calibration element for adjusting said current values for said model parameters based on a response of said array of antenna elements to said control signals,

wherein said adjusting comprises obtaining at least one measured system parameter value and at least one modeled system parameter value for measuring said response, evaluating a difference between said measured system parameter value and said modeled system parameter value, and updating said current values for said model parameters to minimize said difference based on an iterative analysis of said computer simulation model.

20. The communications system of claim 19, wherein said processing element is further configured during said updating for updating at least said current values for said model parameters associated with said measured system parameter value.

21. The communications system of claim 19, wherein said model-based calibration element is configured during said obtaining said measured system parameter value for:

measuring at least one output signal of said one of said plurality of components responsive to said active input parameter;

calculating said measured system parameter value based on said output signal.

22. The communications system of claim 21, wherein said model-based calibration element is configured during said obtaining said estimated parameter value for:

estimating said output signal using a computer simulation of said system, said computer simulation based at least on said computer simulation model, said current values for said model parameters, and said active input parameter;

calculating said modeled system parameter value based on said output signal estimated using said computer simulation.

23. The communications system of claim 22, wherein said computer simulation in said model-based calibration element is further based on at least one of mechanical, a chemical, or an electromagnetic measurement performed in or around said array of antenna elements a system of using a model-based control system to control a physical system having a plurality of components is provided.