Fiber optic impact sensing system and method of using same

• US 20070003182A1
• Filed: 06/29/2005
• Published: 01/04/2007
• Est. Priority Date: 06/29/2005
• Status: Abandoned Application

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Hunn, David
• Application Number:
  US11/169,607
• Publication Number:
  US 20070003182A1
• Time in Patent Office: Days
• US Class Current: 385/12
• CPC Class Codes: G01L 1/242 the material being an optical fibre
• CPC Class Codes: G01M 11/085 the optical fiber being on or near the surface of the DUT

Abstract

A fiber optic impact sensing system includes a light source, an optical detector, and a sensing optical fiber optically coupled with the light source and the optical detector, the sensing optical fiber being operably associated with an outer surface of a structure. An apparatus includes a structure having an outer surface and a fiber optic impact sensing system operably associated with the outer surface of the structure. The fiber optic impact sensing system includes a light source, an optical detector, and a sensing optical fiber optically coupled with the light source and the optical detector. A method includes operably associating a sensing optical fiber with an outer surface of a structure, monitoring an optical output of the sensing optical fiber, and determining whether an amplitude of the optical output is above or below a predetermined threshold value.

Claims

1. A fiber optic impact sensing system, comprising:

a light source;

an optical detector; and

a sensing optical fiber optically coupled with the light source and the optical detector, the sensing optical fiber being operably associated with an outer surface of a structure.

2. The fiber optic impact sensing system, according to claim 1, wherein the light source is optically coupled with a first end of the sensing optical fiber and the optical detector is optically coupled with a second end of the sensing optical fiber.

3. The fiber optic impact sensing system, according to claim 1, further comprising:

a fiber coupler optically coupled with the light source, the optical detector, and the sensing optical fiber,

wherein the sensing optical fiber is a bidirectional optical fiber.

4. The fiber optic impact sensing system, according to claim 3, further comprising a second, bidirectional sensing optical fiber optically coupled with the fiber coupler and operably associated with the outer surface of the structure.

5. The fiber optic impact sensing system, according to claim 1, further comprising:

a cover for protecting the sensing optical fiber.

6. The fiber optic impact sensing system, according to claim 5, wherein the cover comprises:

one of a paint layer and a layer of syntactic foam.

7. The fiber optic impact sensing system, according to claim 1, wherein the optical detector is operable to compare a predetermined threshold value to an amplitude of light outputted from the sensing optical fiber.

8. The fiber optic impact sensing system, according to claim 7, wherein the optical detector is operable to provide an indication of a significant impact if the amplitude of light outputted from the sensing optical fiber is less than about the predetermined threshold value.

9. The fiber optic impact sensing system, according to claim 7, wherein the optical detector is operable to provide an indication of an insignificant impact if the amplitude of light outputted from the sensing optical fiber is greater than about the predetermined threshold value.

10. An apparatus, comprising:

a structure having an outer surface; and

a fiber optic impact sensing system operably associated with the outer surface of the structure, the fiber optic impact sensing system comprising;

a light source;

an optical detector; and

a sensing optical fiber optically coupled with the light source and the optical detector.

11. The apparatus, according to claim 10, wherein the sensing optical fiber is disposed proximate the outer surface of the structure.

12. The apparatus, according to claim 10, wherein the sensing optical fiber is attached to the outer surface of the structure.

13. The apparatus, according to claim 10, further comprising a protective layer disposed over the sensing optical fiber.

14. The apparatus, according to claim 10, wherein the light source is optically coupled with a first end of the sensing optical fiber and the optical detector is optically coupled with a second end of the sensing optical fiber.

15. The apparatus, according to claim 10, further comprising:

a fiber coupler optically coupled with the light source, the optical detector, and the sensing optical fiber,

wherein the sensing optical fiber is a bidirectional optical fiber.

16. The apparatus, according to claim 15, further comprising a second, bidirectional sensing optical fiber optically coupled with the fiber coupler and operably associated with the outer surface of the structure.

17. The fiber optic impact sensing system, according to claim 10, wherein the optical detector is operable to compare a predetermined threshold value to an amplitude of light outputted from the sensing optical fiber.

18. The fiber optic impact sensing system, according to claim 17, wherein the optical detector is operable to provide an indication of a significant impact if the amplitude of light outputted from the sensing optical fiber is less than about the predetermined threshold value.

19. The fiber optic impact sensing system, according to claim 17, wherein the optical detector is operable to provide an indication of an insignificant impact if the amplitude of light outputted from the sensing optical fiber is greater than about the predetermined threshold value.

20. The fiber optic impact sensing system, according to claim 10, wherein the sensing optical fiber is integral with the structure.

21. A method of sensing an impact, comprising:

operably associating a sensing optical fiber with an outer surface of a structure;

monitoring an optical output of the sensing optical fiber; and

determining whether an amplitude of the optical output is above or below a predetermined threshold value.

22. The method, according to claim 21, further comprising:

indicating that a significant impact has occurred if the amplitude of light outputted from the sensing optical fiber is less than about the predetermined threshold value.

23. The method, according to claim 21, further comprising:

indicating that an insignificant impact has occurred if the amplitude of light outputted from the sensing optical fiber is greater than about the predetermined threshold value.