Methods and systems for optical wear sensing

• US 9,297,708 B1
• Filed: 05/14/2012
• Issued: 03/29/2016
• Est. Priority Date: 05/14/2012
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Morris, Charles E., Weaver, Thomas Lyman
• Primary Examiner(s): Ton, Tri T
• Application Number:
  US13/470,734
• Time in Patent Office: 1,415 Days
• Field of Search: 385/12, 385/13, 3562371-2373, 356/600, 356/240, 356/73.1, 250/559.01, 250/559.04, 2505594-55945
• US Class Current: 1/1
• CPC Class Codes: G01L 1/20 by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids of piezo-resistive materials G01L1/18; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress
• CPC Class Codes: G01M 11/086 Details about the embedment of the optical fiber within the DUT
• CPC Class Codes: G01M 5/0025 of elongated objects, e.g. pipes, masts, towers or railways G01M5/0058 takes precedence
• CPC Class Codes: G01M 5/0091 by using electromagnetic excitation or detection

Abstract

Methods and systems for use in monitoring a physical interface between a structural opening and a medium. A system is provided comprising a medium operable to pass through a plurality of structural openings and a sensing system associated with the medium. The sensing system includes at least one physical interface positioned at locations where the medium passes through one of the plurality of structural openings. The at least one physical interface includes at least one waveguide for monitoring changes to the at least one physical interface.

Claims

1. A system comprising:

a medium operable to pass through a plurality of structural openings; and

a sensing system coupled to said medium, wherein said sensing system comprises;

a plurality of physical interfaces each positioned at locations where said medium passes through the plurality of structural openings, said plurality of physical interfaces including a channel defined therethrough and at least one waveguide associated therewith, wherein said at least one waveguide comprises a medium waveguide coupled to said medium, an interface waveguide coupled to said physical interface, and a coupling waveguide coupled between said medium waveguide and said interface waveguide, wherein said interface waveguide completely circumscribes said channel, said medium waveguide, said coupling waveguide, and said interface waveguide configured to pass optical signals therethrough, wherein the ability to pass such optical signals is indicative of monitoring of physical wear to said plurality of physical interfaces;

an emitter configured to channel the optical signals through said at least one waveguide;

a detector coupled in communication with said emitter, wherein said at least one waveguide is coupled between said emitter, said plurality of physical interfaces, and said detector in series such that the optical signals from said emitter are detected at said detector; and

an analysis unit coupled in communication with said detector, said analysis unit configured to determine physical wear to said plurality of physical interfaces based on the optical signals received at said detector.

2. A system in accordance with claim 1, wherein said medium comprises at least one of an electrical cable, a fuel line, and a hydraulic line.

3. A system in accordance with claim 1, wherein said medium comprises a sheath that circumscribes said medium, wherein said sheath includes at least one sheath waveguide for monitoring changes to said sheath, said at least one sheath waveguide is coupled to said sensing system.

4. A system in accordance with claim 3, wherein said at least one sheath waveguide is one of coupled to and embedded within said sheath.

5. A system in accordance with claim 4, wherein said at least one sheath waveguide is coupled to said interface waveguide.

6. A system in accordance with claim 1, wherein said analysis unit comprises an optical phase domain reflectometer.

7. A system in accordance with claim 1, wherein each of said medium waveguide, coupling waveguide, and said interface waveguide is a glass fiber.

8. A system in accordance with claim 7, wherein said at least one physical interface is a grommet having said channel defined therethrough.

9. A method for monitoring a plurality of physical interfaces defined at least partially by a structural opening sized to receive a medium passing therethrough, said method comprising:

applying an optical signal from an emitter to a first end of an optical network coupled to the medium; and

receiving the optical signal at a detector coupled at a second end of the optical network, and coupled to an analysis unit such that an integrity of the optical signal with respect to each location where the optical network and the medium pass through the structural opening is verified, wherein the optical network includes at least one waveguide coupled in series between the emitter, a plurality of physical interfaces, and the detector such that the optical signal is detected at the detector, said at least one waveguide further including a medium waveguide coupled to the medium, an interface waveguide coupled to the physical interface, and a coupling waveguide coupled between the medium waveguide and the interface waveguide, wherein the interface waveguide completely circumscribes the structural opening, wherein the analysis unit is configured to determine physical wear of the physical interfaces based on the optical signal received at the detector.

10. A method in accordance with claim 9, wherein receiving the optical signal comprises verifying an integrity of an optical signal intended to pass through the medium waveguide, the coupling waveguide, and the interface waveguide, wherein the interface waveguide defines a circumference and is embedded within a grommet placed within such structural opening.

11. A method in accordance with claim 10, wherein receiving the optical signal comprises coupling the interface waveguide within the grommet to the medium waveguide via an optical ribbon connector.

12. A method in accordance with claim 9, wherein applying an optical signal to a first end of an optical network associated with the medium comprises transmitting a light pulse from an emitter into the medium waveguide.

13. An apparatus for use with a sensing system, wherein said apparatus is positioned along a plurality of structural openings having a medium passing therethrough, said apparatus comprising:

an annular member sized to fit within each structural opening in the plurality of structural openings;

a channel defined by said annular member, and sized to accommodate the medium; and

at least one interface waveguide positioned within said annular member such that said at least one interface waveguide completely circumscribes said channel, and such that said at least one interface waveguide extends between the plurality of structural openings in series, wherein said interface waveguide is coupled to a coupling waveguide, and wherein said coupling waveguide is coupled to a medium waveguide such that said interface waveguide, said coupling waveguide, said medium waveguide are configured to channel an optical signal therethrough, said signal indicative of physical wear of the apparatus.

14. An apparatus in accordance with claim 13, wherein said interface waveguide enters said apparatus on a first side and exits said apparatus from one of said first side and a second side.

15. An apparatus in accordance with claim 13, wherein said interface waveguide, said coupling waveguide, and said medium waveguide are optical fibers.

16. An apparatus in accordance with claim 13, wherein said annular member is molded from silicone.