Three-dimensional structural damage localization system and method using layered two-dimensional array of capacitance sensors

• US 20070213943A1
• Filed: 02/14/2006
• Published: 09/13/2007
• Est. Priority Date: 02/14/2006
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Curry, Mark, Senibi, Simon, Banks, David
• Granted Patent: US 7,698,075 B2
• Time in Patent Office: Days
• US Class Current: 702/42
• CPC Class Codes: G01M 5/0033 by determining damage, crack or wear
• CPC Class Codes: G01M 5/0091 by using electromagnetic excitation or detection
• CPC Class Codes: G01N 27/24 Investigating the presence of flaws

Abstract

A system and method for detecting damage to a structure is provided. The system includes a voltage source and at least one capacitor formed as a layer within the structure and responsive to the voltage source. The system also includes at least one sensor responsive to the capacitor to sense a voltage of the capacitor. A controller responsive to the sensor determines if damage to the structure has occurred based on the variance of the voltage of the capacitor from a known reference value. A method for sensing damage to a structure involves providing a plurality of capacitors and a controller, and coupling the capacitors to at least one surface of the structure. A voltage of the capacitors is sensed using the controller, and the controller calculates a change in the voltage of the capacitors. The method can include signaling a display system if a change in the voltage occurs.

Claims

1. A system for detecting damage to a structure comprising:

at least one voltage source;

at least one capacitor coupled to the structure and responsive to the voltage source;

at least one sensor responsive to the capacitor to sense a voltage of the capacitor; and

a controller responsive to the sensor to determine if damage to the structure has occurred based on the sensed voltage of the capacitor.

2. The system of claim 1, the capacitor comprising a parallel plate capacitor.

3. The system of claim 2, the capacitor comprising a polyimide film capacitor having layers about 0.01 mil to 3.0 mils thick.

4. The system of claim 1, the capacitor having a capacitance of approximately 175 picoFarads when the structure is undamaged.

5. The system of claim 1, the capacitor having a capacitance of less than 175 picoFarads if damage to the structure has occurred.

6. The system of claim 1, further comprising:

a display system coupled to the controller, the display system responsive to the controller to notify an operator of the mobile platform that damage has occurred to the structure.

7. The system of claim 1, the capacitor comprising a plurality of capacitors arranged in a grid formation with rows and columns of capacitors, and the sensor comprising a plurality of sensors responsive to each of the capacitors and an output sensor responsive to each column of capacitors, the controller operable to query each output sensor sequentially to identify one or more damaged areas of the structure.

8. The system of claim 1, the voltage source responsive to the controller to energize a specific row of the plurality of capacitors.

9. The system of claim 7, the controller adapted to query a column of sensors after the voltage source has energized the row of the plurality of capacitors.

10. The system of claim 1, the capacitor having an increased voltage if damage has occurred to the structure in an immediate vicinity of the capacitor.

11. A method for sensing damage to a structure comprising:

providing a plurality of capacitors;

coupling the capacitors to at least one surface of the structure;

applying a voltage across the capacitors and sensing a voltage of the capacitors;

from the sensed voltage, determining a change in the voltage of the capacitors from a known reference value; and

generating a signal if the sensed voltage deviates from the reference value.

12. The method of claim 11, further comprising:

arranging the capacitors in a grid;

energizing a row of capacitors in the grid with the voltage for a predetermined time;

sensing a voltage across a column of capacitors in the grid; and

using a controller to detect if the sensed voltage across the column deviates from a predetermined reference value for the row of capacitors.

13. The method of claim 12, further comprising:

providing a display system responsive to the controller; and

transmitting a signal to the display system to indicate if the capacitor has been damaged, the display system illuminating an area thereof corresponding to the capacitor to denote whether the capacitor has been damaged.

14. The method of claim 13, wherein illuminating the area of the display system comprises illuminating the area with one of a predetermined shading and color.

15. The method of claim 14, further comprising:

increasing the intensity of the shading of the area based on the amount of detected damage to the capacitor.

16. A structural component comprising:

a structural element;

a capacitor integrated into at least one layer of the structural element to form an integral layer of the structural element;

a sensor electrically coupled to the capacitor for sensing a change in capacitance of the capacitor in the event of an anomaly in the integrity of the structural element; and

a controller for monitoring the sensor and providing an output indicating when the integrity of the structural element has been compromised.

17. The structural component of claim 16, further comprising:

a display system responsive to the output of the controller to notify an individual that the structure is compromised.

18. The structural component of claim 16, the capacitor comprising a plurality of capacitors arranged in a grid of rows and columns of the capacitors, and the sensor comprising a plurality of sensors responsive to each of the capacitors and an output sensor responsive to each said column of capacitors, the controller operable to query each output sensor sequentially.

19. The structural component of claim 18, further comprising:

a voltage source responsive to the controller to energize a row of the plurality of capacitors, the controller adapted to receive a signal from a column of sensors after the voltage source has energized the row of the plurality of capacitors, said signal being indicative of a capacitance of said column of capacitors.

20. The structural component of claim 18, the structural element comprising a plurality of layers with the grid comprising the plurality of capacitors disposed in-between the plurality of layers.