Method and system for processing laser vibrometry data employing bayesian statistical processing techniques

• US 6,672,167 B2
• Filed: 04/23/2001
• Issued: 01/06/2004
• Est. Priority Date: 04/23/2001
• Status: Expired due to Fees

• Current Assignee: Aerospace Corporation, Institute for Advanced Study
• Original Assignee: Aerospace Corporation, Institute for Advanced Study
• Inventors: Shadwick, Bradley A., Buell, Walter F.
• Primary Examiner(s): Williams, Hezron
• Assistant Examiner(s): SAINT SURIN, JACQUES M
• Application Number:
  US09/841,045
• Publication Number:
  US 20030010128A1
• Time in Patent Office: 988 Days
• Field of Search: 735/79, 736/55, 736/56, 735/97, 735/98, 735/99, 736/00, 736/02, 736/57, 356/349, 356/351, 702/56
• US Class Current: 73/657
• CPC Class Codes: G01H 9/00 Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means
• CPC Class Codes: G01N 29/2418 using optoacoustic interaction with the material, e.g. laser radiation, photoacoustics photoacoustic cells G01N21/1702; measuring characteristics of vibrations by using radiation-sensitive means G01H9/00; acousto-optical conversion techniques for short-range imaging G01S15/8965; sound-producing devices using laser bundle G10K15/046
• CPC Class Codes: G01N 29/4472 Mathematical theories or simulation
• CPC Class Codes: G01N 29/449 Statistical methods not provided for in G01N29/4409, e.g. averaging, smoothing and interpolation
• CPC Class Codes: G01N 29/52 using inversion methods other that spectral analysis, e.g. conjugated gradient inversion

Abstract

A method and system for processing laser vibrometry data are embodied in a processor configured to employ a statistical signal processing technique (e.g., a Bayesian processing technique) to process one or more mathematical models, laser vibrometry data for a system under observation, and prior information to generate estimates of parameters for the one or more mathematical models.

Claims

1. A laser vibrometry method comprising the steps of:

employing a laser to generate laser vibrometry data for a system under observation;

performing Bayesian parameter estimation calculations for a mathematical model of the system under observation, the laser vibrometry data and prior information to generate estimations of parameters of the mathematical model;

evaluating the estimations of parameters; and

if desired or necessary, repeating the step of performing Bayesian parameter estimation calculations with a different model and/or different laser vibrometry data.

2. The laser vibrometry method of claim 1, wherein the system under observation comprises a reflective target in motion.

3. The laser vibrometry method of claim 1, wherein the laser vibrometry data comprises continuous wave (CW) laser vibrometry data.

4. The laser vibrometry method of claim 1, wherein the laser vibrometry data comprises dual pulse coherent laser vibrometry data.

5. The laser vibrometry method of claim 1, wherein the laser vibrometry data comprises vibrational imaging data.

6. The laser vibrometry method of claim 1, wherein the prior information comprises noise information.

7. The laser vibrometry method of claim 6, wherein the noise information pertains to a signal-to-noise ratio.

8. The laser Vibrometry method of claim 6, wherein the noise information is assigned a least informative probability density.

9. The laser vibrometry method of claim 1, wherein the step of evaluating parameter estimation results includes evaluating vibration frequencies.

10. The laser vibrometry method of claim 1, wherein the step of evaluating parameter estimation results includes evaluating variances of parameter estimates.

11. The laser vibrometry method of claim 1, wherein the step of evaluating parameter estimation results includes evaluating higher order moments.

12. The A laser vibrometry method comprising the steps of:

creating one or more mathematical models of a system under observation;

employing a laser to generate laser vibrometry data for the system under observation;

processing the one or more mathematical models, the laser vibrometry data and prior information employing a statistical signal processing technique to generate estimates of parameters for the one or more mathematical models;

performing an evaluation of the parameter estimations; and

if results of the evaluation are determined not to be satisfactory, repeating the processing step with a different model and/or different laser vibrometry data.

13. The laser vibrometry method of claim 12, wherein the statistical signal processing technique comprises a Bayesian processing technique.

14. The laser vibrometry method of claim 12, wherein the one or more mathematical models are models of the system under observation.