Laminate material testing methods and systems

• US 7,222,514 B2
• Filed: 06/21/2004
• Issued: 05/29/2007
• Est. Priority Date: 06/21/2004
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Kollgaard, Jeffrey R., Fetzer, Barry A., Uyehara, Clyde T., Thompson, Jeffrey G.
• Primary Examiner(s): CHAPMAN JR, JOHN E
• Application Number:
  US10/870,962
• Publication Number:
  US 20050279171A1
• Time in Patent Office: 1,072 Days
• Field of Search: 73/18.2, 73/18.6, 735/88, 736/09
• US Class Current: 73/1.82
• CPC Class Codes: G01N 2291/0231 Composite or layered materials
• CPC Class Codes: G01N 2291/048 Transmission, i.e. analysed material between transmitter and receiver
• CPC Class Codes: G01N 29/0645 Display representation or displayed parameters, e.g. A-, B- or C-Scan
• CPC Class Codes: G01N 29/30 Arrangements for calibrating or comparing, e.g. with standard objects

Abstract

Techniques for ultrasonically evaluating damage to a laminate structure include use of a diagnostic device having at least two modes of operation including a calibration mode and a test mode with the calibration mode providing calibration parameters specific to the laminate structure under test.

Claims

1. A method for evaluating damage to a laminate structure having a front-surface and a back-surface, the method comprising:

calibrating a diagnostic device using an undamaged portion of the laminate structure to determine a plurality of calibration parameters in response to a transducer being pressed against the undamaged portion of the laminate structure and only a calibration button being pressed, wherein the calibration parameters include a return calibration pulse amplitude and a return calibration pulse timing;

performing one or more test cycles to a suspect portion of the laminate structure using the one or more of the calibration parameters in response to the transducer being pressed against the suspect portion of the laminate structure and only an activation button being pressed, wherein the one or more test cycles includes transmitting a pulse into the laminate structure and sensing a plurality of test parameters, the test parameters including a return testing pulse amplitude and a return testing pulse timing;

comparing the return calibration parameters to the test parameters; and

activating a damage indicator in response to the comparison of the return calibration parameters to the test parameters exceeding a predetermined acceptable difference.

2. The method of claim 1, wherein the diagnostic device emits an ultrasonic pulse having a first frequency, and wherein the diagnostic device is configured to detect returned pulse energy of the first frequency.

3. The method of claim 2, wherein the first frequency is between from about 2.5 MHz to about 10 MHz.

4. The method of claim 3, wherein the first frequency is about 5 MHz.

5. The method of claim 2, wherein the emitted ultrasonic pulse has a generally bell-shaped amplitude profile.

6. The method of claim 1, wherein the step of calibrating includes touching the diagnostic device to the surface of the laminate structure at the undamaged portion.

7. The method of claim 6, wherein performing a test cycle includes touching the diagnostic device to the surface of the laminate structure at the suspect portion.

8. A method for ultrasonically testing a laminate structure having a front-surface and a back-surface, the method comprising:

performing a test cycle on a suspect portion of the laminate structure based on an ultrasonic echo-profile in response to a transducer being pressed against the suspect portion of the laminate structure and only an activation button being pressed;

comparing test cycle parameters to calibration parameters, the test cycle parameter including a return test cycle pulse amplitude and a return test cycle pulse timing, the calibration parameters including a return calibration pulse amplitude and a return calibration pulse timing;

determining whether the suspect portion of the laminate structure conforms to the calibration parameters, the calibration parameters providing information about an undamaged portion of the particular laminate structure under test; and

activating a damage indicator in response to the suspect portion not conforming to the calibration parameters.

9. The method of claim 8, further comprising determining a type of damage based on the echo-profile.

10. The method of claim 8, further comprising determining damage depth based on the echo-profile.

11. A method for calibrating a diagnostic device capable of detecting latent damage in a laminate structure, the method comprising:

emitting an ultrasonic pulse into the laminate structure in response to the diagnostic device being pressed against the undamaged portion of the laminate structure and only a calibration button being pressed;

detecting an echo-profile of the laminate structure in response to the emitted ultrasonic pulse; and

determining a plurality of calibration parameters in response to the detected echo-profiles, the calibration parameters providing information about an undamaged portion of the laminate structure under test, wherein the calibration parameters include a return calibration pulse amplitude and a return calibration pulse timing and wherein the calibration parameters are compared to a plurality of test parameters to test the laminate structure, the test parameters including a return testing pulse amplitude and a return testing pulse timing.

12. A laminate diagnostic apparatus, comprising:

a laminate measuring means for sonically evaluating a laminate structure in response to the laminate diagnostic apparatus being pressed against the laminate structure and only an activation button being pressed, the laminate measuring means comprising;

a pulse generating means to generate a pulse;

a pulse sensing means to sense a return pulse amplitude and a return pulse timing; and

a comparing means to compare the return pulse amplitude and the return pulse timing to a calibration pulse amplitude and calibration pulse timing; and

a display means coupled to the measuring means for providing a damaged/not damaged indication of the laminate structure based on a signal from the measuring means.

13. The laminate diagnostic apparatus of claim 12, wherein the measuring means employs a calibration cycle for measuring an undamaged portion of the laminate structure.

14. The laminate diagnostic apparatus of claim 13, wherein the measuring means further employs a test cycle for evaluating a suspect portion of the laminate structure.

15. The laminate diagnostic apparatus of claim 14, wherein the measuring means uses information about the laminate structure developed during the calibration cycle to evaluate the laminate structure during the test cycle.

16. The laminate diagnostic apparatus of claim 12, wherein the display means provides a damaged/undamaged indication.

17. The laminate diagnostic apparatus of claim 16, wherein the display means further provides a depth indication of a damaged portion within the laminate.

18. The laminate diagnostic apparatus of claim 17, wherein the display means further provides a damage-type indication of the damaged portion.

19. A diagnostic apparatus for evaluating an amount of damage to a laminate structure, comprising:

a test manager coupled to a data-acquisition device and a sonic transducer;

wherein the diagnostic apparatus compares a calibration cycle and a test cycle, the calibration cycle including a pulse amplitude calibration and a pulse timing calibration, the test cycle including a pulse amplitude test and a pulse timing test, wherein the calibration cycle produces a plurality of calibration parameters in response to the diagnostic apparatus being pressed against the laminate structure and only a calibration button being pressed, and wherein the test cycle uses the one or more of the calibration parameters to evaluate whether a portion of the laminate structure is damaged in response to the diagnostic apparatus being pressed against the laminate structure and only an activation button being pressed.

20. The diagnostic apparatus of claim 19, wherein the calibration parameters provide information about an undamaged portion of the particular laminate structure under test.