Method and apparatus for defect detection in composite structures

Patent metadata

Field	Value
Publication number	US-9494562-B2
Application number	US-201113977319-A
Country	US
Kind code	B2
Filing date	May 27, 2011
Priority date	Dec 29, 2010
Publication date	Nov 15, 2016
Grant date	Nov 15, 2016

Abstract

Methods and apparatus for non-destructive testing of a composite structure utilizing sonic or ultrasonic waves. In response to a wideband chirp wave sonic excitation signal transmitted from a probe to the composite structure, a probe signal received is correlated with a library of predetermined probe signals and a graphical representation of defects detected is generated. The graphical representation provides detailed information on defect type, defect location and defect shape. Also contemplated is a probe for non-destructive testing of a composite structure comprising three or more transducers wherein each transducer is separately configurable as a transmitter or as a receiver; and a controller coupled to each of transducer for providing signals thereto and receiving signals therefrom, wherein the signals provided thereto include signals for configuring each transducer as either a transmitter or a receiver, and signals for providing an excitation signal from each transducer which is configured as a transmitter.

First claim

What is claimed is:

1. A method for non-destructive testing of a composite structure comprising:
providing a wideband chirp wave sonic signal to the composite structure for a predetermined time having a predetermined amplitude and a predetermined range of frequencies as an excitation signal;
correlating a probed signal received from the composite structure with a library of predetermined probed signals, the library of predetermined probe signals comprising probe signals received from a reference composite structure generated in response to the wideband chirp wave sonic signal provided to the reference composite structure for the predetermined time having the predetermined amplitude and the predetermined frequency, wherein the reference composite structure includes one or more predefined defects; and
outputting a graphical representation of defects detected, wherein the graphical representation of the defects detected conveys defect type information.

2. The method in accordance with claim 1 wherein the step of providing the wideband chirp wave sonic signal comprises providing the wideband chirp wave sonic signal to the composite structure as the excitation signal at a predetermined range of frequencies between twenty kilohertz (20 kHz) and forty kilohertz (40 kHz) with a frequency of the excitation signal either decreasing or increasing over the predetermined time.

3. The method in accordance with claim 1 wherein the step of providing the wideband chirp wave sonic signal comprises providing the wideband chirp wave sonic signal to the composite structure as the excitation signal having a predetermined high amplitude of less than one hundred volts peak-to-peak.

4. The method in accordance with claim 1 wherein the step of providing the wideband chirp wave sonic signal comprises providing the wideband chirp wave sonic signal to the composite structure for a predetermined time duration less than ten milliseconds as the excitation signal.

5. The method in accordance with claim 1 wherein the library of predetermined probed signals comprises a library of phase shift fast Fourier transformations of the probed signals calculated from the phase shift fast Fourier transformations of the probed signals received from the reference composite structure over a range of frequencies.

6. The method in accordance with claim 1 wherein the library of predetermined probed signals comprises predetermined probed signals generated in response to magnitudes of fast Fourier transformations of the probed signals received from the reference composite structure.

7. The method in accordance with claim 1 wherein the step of outputting the graphical representation of defects detected comprises outputting the graphical representation of defects detected, wherein the graphical representation of the defects detected convey defect size information, defect type information and the defect location information.

8. The method in accordance with claim 1 wherein the step of outputting the graphical representation of defects detected comprises outputting the graphical representation of defects detected, wherein a visual presentation of the graphical representation of the defects detected comprises one or more visual presentation parameters such as shape or color for conveying information including defect location information, defect size information or the defect type information.

9. The method in accordance with claim 1 wherein the step of correlating a probed signal comprises correlating a fast Fourier transformation of the probed signal received from the composite structure with the library of predetermined probed signals, wherein the library of predetermined probed signals comprises a library of phase shift fast Fourier transformations of probed signals received from the reference composite structure over a range of frequencies.

10. The method in accordance with claim 1 wherein the step of correlating a probed signal comprises correlating a magnitude of a fast Fourier transformation of the probed signal received from the composite structure with the library of predetermined probed signals, wherein the library of predetermined probed signals comprises a library of predetermined probed signals calculated in response to magnitudes of fast Fourier transformations of probed signals received from the reference composite structure.

11. An apparatus for non-destructive testing of a composite structure comprising:
a transmitter providing a wideband chirp wave sonic signal to the composite structure for a predetermined time, a predetermined amplitude and over a predetermined range of frequencies as an excitation signal;
a receiver for receiving a probed signal from the composite structure in response to the excitation signal;
a user interface for presenting a graphical representation of defects detected;
a storage device for storing a library of predetermined probed signals, the library of predetermined probe signals comprising probe signals received by the receiver from a reference composite structure including one or more predefined defects, the probe signals generated in response to a wideband chirp wave sonic signal produced by the transmitter to the reference composite structure for the predetermined time having the predetermined amplitude and the predetermined frequency, wherein a controller thereafter provides the library of predetermined probed signals to the storage device for storing therein; and
the controller coupled to the receiver, the storage device and the user interface for correlating the probed signal received with the library of predetermined probed signals and providing signals to the user interface for outputting a graphical representation of defects detected conveying defect location information.

12. The apparatus in accordance with claim 11 wherein the controller is coupled to the transmitter and generates signals for providing thereto to provide the wideband chirp wave sonic signal to the composite structure as the excitation signal at a predetermined frequency range between twenty kilohertz (20 kHz) and forty kilohertz (40 kHz) with a frequency of the excitation signal either decreasing or increasing over the predetermined time.

13. The apparatus in accordance with claim 11 wherein the controller is coupled to the transmitter and generates signals for providing thereto to provide the wideband chirp wave sonic signal to the composite structure as the excitation signal having a predetermined high amplitude of less than one hundred volts peak-to-peak.

14. The apparatus in accordance with claim 11 wherein the controller is coupled to the transmitter and generates signals for providing thereto to provide the wideband chirp wave sonic signal to the composite structure for a predetermined time duration less than ten milliseconds as the excitation signal.

15. The apparatus in accordance with claim 11 wherein the controller provides signals to the user interface for outputting a graphical representation of defects detected conveying defect type information, defect size information and the defect location information.

16. The apparatus in accordance with claim 11 wherein the user interface presents a visual presentation of the graphical representation of the defects detected comprising one or more visual presentation parameters such as shape or color for conveying information including defect type information, defect size information or the defect location information.

17. The apparatus in accordance with claim 11 wherein the transmitter comprises one or more transmitters and the receiver comprises one or more

Assignees

• Lin Wei
• Goh Lay Siong
• Wong Lye Seng
• Hey Heng Kiat Jonathan
• Chan Ricky Riyadi
• Britner Roman
• Agency Science Tech & Res

Inventors

• Lin Wei
• Goh Lay Siong
• Wong Lye Seng
• Hey Heng Kiat Jonathan
• Chan Ricky Riyadi
• Britner Roman

Classifications

• G01N29/46

  by spectral analysis, e.g. Fourier analysis {or wavelet analysis (spectral signal processing per se G06F17/14)} · CPC title

• G01N29/4427 Primary

  with stored values, e.g. threshold values · CPC title

• G01N29/348

  with frequency characteristics, e.g. single frequency signals, chirp signals (measuring frequency of mechanical vibrations or acoustic waves in general G01H1/06, G01H3/04; measuring frequency or analysing frequency spectra G01R23/00) · CPC title

• G01N29/4445

  Classification of defects · CPC title

• G01N2291/0231

  Composite or layered materials · CPC title