Method and apparatus for automatically detecting patterns in digital point-ordered signals

• US 5,825,672 A
• Filed: 10/25/1996
• Issued: 10/20/1998
• Est. Priority Date: 10/25/1996
• Status: Expired due to Fees

• Current Assignee: United States Department of Energy (Government of the United States of America)
• Original Assignee: United States Department of Energy (Government of the United States of America)
• Inventors: Brudnoy, David M.
• Primary Examiner(s): Trammell, James P.
• Assistant Examiner(s): Bui, Bryan
• Application Number:
  US08/736,751
• Time in Patent Office: 725 Days
• Field of Search: 364/481-482, 364/485, 364/487, 364/506, 364/551.01, 364/552, 364/556, 364/572-576, 364/724.01, 324/76.11, 324/76.12, 324/76.47, 324/696, 324/715, 324/76.24, 324/76.15, 324/76.42, 600/509, 600/528, 600/546, 600/544, 600/518, 600/517, 600/521, 128/696, 128/732
• US Class Current: 702/191
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/7235 Details of waveform analysis A61B5/349 takes precedence

Abstract

The present invention is a method and system for detecting a physical feature of a test piece by detecting a pattern in a signal representing data from inspection of the test piece. The pattern is detected by automated additive decomposition of a digital point-ordered signal which represents the data. The present invention can properly handle a non-periodic signal. A physical parameter of the test piece is measured. A digital point-ordered signal representative of the measured physical parameter is generated. The digital point-ordered signal is decomposed into a baseline signal, a background noise signal, and a peaks/troughs signal. The peaks/troughs from the peaks/troughs signal are located and peaks/troughs information indicating the physical feature of the test piece is output.

Claims

1. An automated, computer-implemented method for detecting signal information representing a physical feature of a test piece by detecting a pattern in a signal representing data from inspection of the test piece, comprising the steps of:

measuring a physical parameter of the test piece;

generating a digital point-ordered signal representative of the measured physical parameter;

decomposing the digital point-ordered signal into three components, based on resolution, comprising a coarse resolution baseline signal, a fine resolution background noise signal, and an intermediate resolution peaks/troughs signal;

locating peaks/troughs from the peaks/troughs signal; and

outputting peaks/troughs information identifying those signal patterns that indicate the presence of physical features of the test piece.

2. The method of claim 1, wherein the test piece is a mechanical object and the measured physical parameter is the acceleration measured at a location on the mechanical object.

3. The method of claim 1, wherein the test piece is a metallic piece and the measured physical parameter is the impedance produced by electromagnetic probing of the metallic piece.

4. The method of claim 1, wherein the test piece is a living organism and the measured physical parameter is the electrical activity within the living organism.

5. The method of claim 1, wherein the decomposing step comprises the steps of:

generating a morphologically filtered signal from the digital point-ordered signal;

generating a baseline signal from the morphologically filtered signal;

generating a background noise signal from the baseline signal and the digital point-ordered signal; and

generating a peaks/trough signal from the baseline signal, the background noise signal and the digital point-ordered signal.

6. The method of claim 5, wherein the baseline signal comprises coarse resolution behavior of the digital point-ordered signal relative to the background noise signal and the peaks/troughs signal.

7. The method of claim 5, wherein the background noise signal comprises fine resolution behavior of the digital point-ordered signal relative to the baseline signal and the peaks/troughs signal.

8. The method of claim 5, wherein the peaks/troughs signal comprises intermediate resolution behavior of the digital point-ordered signal relative to the baseline signal and the background noise signal.

9. The method of claim 8, wherein the decomposing step is performed at a first resolution level and the method further comprises the step of:

decomposing the peaks/troughs signal constructed at the first resolution level into a baseline signal, a background noise signal, and a peaks/troughs signal constructed at a second resolution level, the second resolution level being finer than the first resolution level.

10. The method of claim 1 wherein the signal representing data from inspection of the test piece is a non-periodic signal.

11. An automated, computer-implemented method for detecting a physical feature of a test piece by detecting a pattern in a signal representing data from inspection of the test piece, comprising the steps of:

measuring a physical parameter of the test piece;

generating a digital point-ordered signal representative of the measured physical parameter;

generating a morphologically filtered signal from the digital point-ordered signal;

generating a baseline signal from the morphologically filtered signal, the baseline signal comprising a coarse resolution behavior of the digital point-ordered signal relative to the background noise signal and the peaks/troughs signal;

generating a background noise signal from the baseline signal and the digital point-ordered signal, the background noise signal comprising fine resolution behavior of the digital point-ordered signal relative to the baseline signal and the peaks/troughs signal;

generating a peaks/troughs signal from the baseline signal, the background noise signal and the digital point-ordered signal the peaks/troughs signal comprising intermediate resolution behavior of the digital point-ordered signal relative to the baseline signal and the background noise signal;

locating peaks/troughs from the peaks/troughs signal; and

outputting peaks/troughs information indicating the physical feature of the test piece.

12. In a test system comprising a test piece, means for measuring a physical parameter of the test piece and means for generating a digital point-ordered signal representative of the measured physical parameter, an apparatus for detecting signal information representing a physical feature of the test piece by detecting a pattern in the signal representative of the measured physical parameter, comprising:

means, coupled to the means for generating the digital point-ordered signal, for decomposing the digital point-ordered signal into a baseline signal, a background noise signal, and a peaks/troughs signal;

wherein the decomposing means comprises;

means, coupled to the means for generating the digital point-ordered signal, for generating a morphologically filtered signal from the digital point-ordered signal;

means, coupled to the morphological filtering means, for generating a baseline signal from the morphologically filtered signal;

means, coupled to the baseline signal generating means, for generating a background noise signal from the baseline signal and the digital point-ordered signal; and

means, coupled to the background noise seal generating means, for generating a peaks/troughs component signal from the baseline signal, the background noise signal and the digital point-ordered signal;

means, coupled to the decomposing means, for locating peaks/troughs from the peaks/troughs signal; and

means, coupled to the locating means, for outputting peaks/troughs information indicating the presence of physical features of the test piece.

13. The test system of claim 12, wherein the test piece is a mechanical object and the measured physical parameter is the acceleration at a location on the mechanical object.

14. The test system of claim 12, wherein the test piece is a metallic piece and the measured physical parameter is the impedance produced by electromagnetic probing of the metallic piece.

15. The test system of claim 12, wherein the test piece is a living organism and the measured physical parameter is the electrical activity within the living organism.

16. The system of claim 12, wherein the baseline signal comprises coarse resolution behavior of the digital point-ordered signal relative to the background noise signal and the peaks/troughs signal.

17. The system of claim 12, wherein the background noise signal comprises fine resolution behavior of the digital point-ordered signal relative to the baseline signal and the peaks/troughs signal.

18. The system of claim 12, wherein the peaks/troughs signal comprises intermediate resolution behavior of the digital point-ordered signal relative to the baseline signal and the background noise signal.

19. The system of claim 18, wherein the peaks/troughs component signal generating means generates a peaks/troughs component signal at a first resolution level and the system further comprises:

means for decomposing the peaks/troughs signal constructed at the first resolution level into a baseline signal, a background noise signal, and a peaks/troughs signal constructed at a second resolution level, the second resolution level being finer than the first resolution level.

20. In a test system comprising a test piece, means for measuring a physical parameter of the test piece and means for generating a digital point-ordered signal representative of the measured physical parameter, an apparatus for detecting a physical feature of the test piece by detecting a pattern in the signal representative of the measured physical parameter, comprising:

means, coupled to the means for generating the digital point-ordered signal, for generating a morphologically filtered signal from the digital point-ordered signal;

means, coupled to the morphological filtering means, for generating a baseline signal from the morphologically filtered signal, the baseline signal comprising coarse resolution behavior of the digital point-ordered signal relative to the background noise signal and the peaks/troughs signal;

means, coupled to the baseline signal generating means, generating a background noise signal from the baseline signal and the digital point-ordered signal, the background noise signal comprising fine resolution behavior of the digital point-ordered signal relative to the baseline signal and the peaks/troughs signal;

means, coupled to the background noise signal generating means, generating a peaks/trough signal from the baseline signal, the background noise signal and the digital point-ordered signal the peaks/troughs signal comprising intermediate resolution behavior of the digital point-ordered signal relative to the baseline signal and the background noise signal;

means, coupled to the peaks/trough component signal generating means, for locating peaks/troughs from the peaks/troughs signal; and

means, coupled to the locating means, for outputting peaks/troughs information indicating the physical feature of the test piece.

21. The system of claim 20, wherein the peaks/troughs component signal generating means generates a peaks/troughs component signal at a first resolution level and the system further comprises:

means for decomposing the peaks/troughs signal constructed at the first resolution level into a baseline signal, a background noise signal, and a peaks/troughs signal constructed at a second resolution level, the second resolution level being finer than the first resolution level.

22. An automated, computer-implemented method for detecting a physical feature of a test piece by detecting a pattern in a signal representing data from inspection of the test piece, comprising the steps of:

measuring a physical parameter of the test piece;

generating a digital point-ordered signal representative of the measured physical parameter;

decomposing the digital point-ordered signal into a baseline signal, a background noise signal, and a peaks/troughs signal;

wherein the decomposing step comprises the steps of;

generating a morphologically filtered signal from the digital point-ordered signal;

generating a baseline signal from the morphologically filtered signal;

generating a background noise signal from the baseline signal and the digital point-ordered signal; and

generating a peaks/troughs signal from the baseline signal, the background noise signal and the digital point-ordered signal;

locating peaks/troughs from the peaks/troughs signal; and

outputting peaks/troughs information identifying those signal patterns that indicate the presence of physical features of the test piece.