Optical fiber mounting and structural monitoring

• US 4,930,852 A
• Filed: 02/21/1989
• Issued: 06/05/1990
• Est. Priority Date: 02/21/1989
• Status: Expired due to Term

• Current Assignee: Simmonds Precision Products, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: Simmonds Precision Products, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Wheeler, Richard G., Robinson, Roy
• Primary Examiner(s): Gonzalez, Frank
• Assistant Examiner(s): Ullah, Akm E.
• Application Number:
  US07/313,262
• Time in Patent Office: 469 Days
• Field of Search: 350/96.10, 350/96.23, 350/96.24, 350/96.29, 250/227, 250/231 P, 250/231 R, 250/577, 250/578, 73/800, 73/802
• US Class Current: 359/315
• CPC Class Codes: G01M 11/086 Details about the embedment of the optical fiber within the DUT

Abstract

An optical fiber mounting device and method of installation and monitoring of a structure using the device. The device includes an optical fiber connected to a support sheet. The support sheet is readily adapted to be connected to a structure. The method of installation of the device includes affixing the support sheet to a structure. The fabricated structure is monitored by propagating light through the installed optical fiber and continuously monitoring the light to detect changes in temperature, pressure, stress and/or strain in the structure.

Claims

1. An optical fiber mounting device, consisting essentially of:

an optical fiber and

a support sheet of fabric,

said optical fiber being connected to said sheet of fabric,

said sheet having a release coating on at least one side of said fabric.

2. The device of claim 1 wherein said optical fiber is characterized by attenuation of light intensity by less than 100 dB per kilometer of length of said optical fiber as said light is propagated through said optical fiber.

3. The device of claim 1 wherein said support sheet comprises graphite fiber.

4. The device of claim 1 wherein said support sheet and said optical fiber are wound into a roll, and said support sheet comprises structural fibers.

5. The fiber of claim 1 in combination with an optical source, an optical detector, a microprocessor, a memory, electrical conductors and a display, said optical source being adapted to transmit light into said optical fiber, said optical detector being adapted to detect light emanating from said optical fiber, said microprocessor being connected by said electrical conductors to said optical source, said optical detector, said memory and said display.

6. The device of claim 1 further comprising a structure, said sheet being connected to said structure.

7. The device of claim 6 wherein said structure is an aircraft.

8. The device of claim 1 wherein said sheet comprises woven structural fiber.

9. The device of claim 1 wherein said sheet comprises an adhesive coating on at least one side of said sheet.

10. The device of claim 1 in combination with an optical connector.

11. The device of claim 11 in combination with an optical source and an optical detector.

12. A method of connecting an optical fiber to a structure, comprising:

providing an optical fiber connected to a substantially nonmetal support sheet,

said sheet having a release coating on at least one side of said sheet,

providing a structure, and

connecting said sheet to said structure whereby said optical fiber is installed.

13. The method of claim 12 wherein said optical fiber is characterized by attenuation of light intensity by less than 100 dB per kilometer of length of said optical fiber as said light is propagated through said optical fiber.

14. The method of claim 12 wherein said sheet comprises graphite fiber, and said fiber and said sheet are wound into a roll and then unwound from a said roll and cut before being affixed to said structure.

15. The method of claim 12 wherein said structure is an aircraft or an airfoil.

16. The method of claim 14 wherein said structure is an aircraft and said sheet is affixed to said aircraft by resin.

17. The method of claim 12 further comprising providing an optical source, an optical detector, a microprocessor, a memory, electrical conductors and a display, said optical source being adapted to transmit light into said optical fiber, said optical detector being adapted to detect light emanating from said optical fiber, said microprocessor being connected by said electrical conductors to said optical source, said optical detector, said memory and said display.

18. The method of claim 17 further comprising emitting light from said optical source into said optical fiber and monitoring said light emanating from said optical fiber to detect the magnitude and location of stress and/or strain in said structure.

19. The method of claim 18 wherein said structure comprises graphite fiber.

20. The method of claim 18 wherein said structure comprises a thermoset polymer passing light into said optical fiber.

21. The method of claim 18 further comprising passing light into said optical fiber monitoring the magnitude and location of movement in said structure by detecting changes in characteristics of said light.