System and Method for Progressive Damage Monitoring and Failure Event Prediction in a Composite Structure

• US 20170052150A1
• Filed: 08/16/2016
• Published: 02/23/2017
• Est. Priority Date: 08/20/2015
• Status: Active Grant

• Current Assignee: National Institute of Aerospace Asscoiates, United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Original Assignee: U.S.A. as represented by the Administrator of the National Aeronautics and Space Administration
• Inventors: ZALAMEDA, Joseph N., HORNE, MICHAEL R., MADARAS, ERIC I., BURKE, ERIC R.
• Granted Patent: US 10,605,783 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01L 1/00 Measuring force or stress, in general measuring force due to impact G01L5/00
• CPC Class Codes: G01N 2021/8472 Investigation of composite materials
• CPC Class Codes: G01N 21/84 Systems specially adapted for particular applications
• CPC Class Codes: G01N 21/8803 Visual inspection measuring projectors G01B9/08
• CPC Class Codes: G01N 2291/0231 Composite or layered materials
• CPC Class Codes: G01N 2291/0258 Structural degradation, e.g. fatigue of composites, ageing of oils
• CPC Class Codes: G01N 2291/106 one or more transducer arrays
• CPC Class Codes: G01N 2291/2694 Wings or other aircraft parts
• CPC Class Codes: G01N 29/043 in the interior, e.g. by shear waves
• CPC Class Codes: G01N 29/069 Defect imaging, localisation and sizing using, e.g. time of flight diffraction [TOFD], synthetic aperture focusing technique [SAFT], Amplituden-Laufzeit-Ortskurven [ALOK] technique
• CPC Class Codes: G01N 29/14 using acoustic emission techniques echo of particles G01N29/046; measuring mechanical vibrations or acoustic waves in solids in general G01H1/00

Abstract

A system for monitoring damage progression in a composite structure includes a load sensor, acoustic emission sensors, a camera, and a monitoring device. The load sensor measures an applied load to the structure. The sensors measure acoustic emission data indicative of possible damage to the structure. The camera captures image data of the structure in a designated portion of the electromagnetic spectrum. The monitoring device executes a method by which the acoustic emission data is synchronously collected with the image data and the applied load. The device automatically maps the acoustic emission data onto the image data to detect an area of damage progression in the composite structure. A failure event in the detected area of damage progression may be predicted using the mapped data, and a control action may be executed in response to the predicted failure event.

Claims

1. A system for monitoring damage progression in a composite structure subjected to an applied load, the system comprising:

a load sensor operable for measuring the applied load and outputting a load profile signal indicative of the measured applied load;

an array of acoustic emission sensors operable for measuring acoustic emission data indicative of possible damage to the composite structure;

a camera operable for capturing image data of the composite structure in a designated portion of the electromagnetic spectrum; and

a monitoring device in communication with the load sensor, the acoustic emission sensors, and the camera, wherein the monitoring device is configured to synchronously measure the applied load via the load sensor, collect the acoustic emission data via the acoustic emission sensors, and collect the image data via the camera, and to automatically map the collected acoustic emission data onto the collected image data to thereby detect an area of damage progression in the composite structure.

2. The system of claim 1, wherein the monitoring device is configured to predict a failure event in the detected area of damage progression using the mapped acoustic emission data and image data, and to execute a control action with respect to the composite structure in response to the predicted failure event.

3. The system of claim 2, wherein the control action includes recording, via the monitoring device, the measured applied load and a duration between an onset of the damage and the predicted failure event.

4. The system of claim 3, further comprising:

a maintenance device programmed to receive the acoustic emission data and the load profile signal, and to execute a failure prediction model to thereby predict, in real time, an occurrence of the failure in the composite structure.

5. The system of claim 1, wherein the camera is configured to capture the image data in an infrared range of the electromagnetic spectrum.

6. The system of claim 1, wherein the camera is configured to capture the image data in a visible range of the electromagnetic spectrum.

7. The system of claim 1, wherein the camera includes a first camera oriented toward a first surface of the composite structure and a second camera oriented toward a second surface of the composite structure.

8. The system of claim 1, wherein the load sensor is mechanically coupled to the composite structure.

9. The system of claim 1, wherein the load sensor is configured to remotely sense a displacement of the composite structure in response to the applied load.

10. The system of claim 1, wherein the monitoring device is configured to control a resolution of the camera in a targeted area of the composite structure as a function of a severity of the acoustic emission data in the targeted area.

11. A method for monitoring damage progression in a composite structure subjected to an applied load, the method comprising:

measuring acoustic emission data, via an array of acoustic emission sensors each acoustically coupled to the composite structure, when the composite structure is subjected to the applied load, wherein the acoustic emission data is indicative of possible damage to the composite structure;

synchronously collecting image data via a camera in a designated portion of the electromagnetic spectrum;

measuring the applied load via a load sensor while synchronously collecting the acoustic emission data and the image data; and

automatically mapping the collected acoustic emission data onto the collected image data via a programmable monitoring device to thereby detect an area of damage progression in the composite structure corresponding to the applied load.

12. The method of claim 11, further comprising:

predicting a failure event in the detected area of damage progression via the monitoring device using the mapped collected acoustic emission and image data; and

executing a control action with respect to the composite structure in response to the predicted failure event.

13. The method of claim 12, wherein predicting the failure event includes calculating a total energy in the acoustic emission event using the acoustic emission signal.

14. The method of claim 13, wherein executing a control action includes:

displaying a graphical indicator indicative of the total energy level of the acoustic emission event on an image of the composite structure via the programmable monitoring device, with at least one of a color, a size, and an opacity of the graphical indicator corresponding to the total energy level.

15. The method of claim 11, further comprising:

controlling a frame rate or a resolution of the camera in a targeted area of the composite structure based on a level of the acoustic emission data in the targeted area.

16. The method of claim 11, further comprising:

receiving, via a maintenance device programmed with a failure prediction model, a load profile signal from the load sensor indicative of the measured applied load; and

using the load profile signal, the acoustic emission data, and the failure prediction model to predict, in real time, an occurrence of a failure event in the composite structure.

17. The method of claim 11, wherein the camera is configured to capture the image data in an infrared range of the electromagnetic spectrum.

18. The method of claim 11, wherein the camera is configured to capture the image data in a visible range of the electromagnetic spectrum.

19. The method of claim 11, wherein automatically mapping the acoustic emission data includes using delayed image subtraction to optimize defect contrast in the collected image data.

20. The method of claim 11, further comprising:

removing optical barrel distortion from the collected image data before automatically mapping the acoustic emission data onto the image data.