Wireless damage location sensing system

• US 8,167,204 B2
• Filed: 10/17/2008
• Issued: 05/01/2012
• Est. Priority Date: 10/19/2007
• Status: Active Grant

• Current Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Original Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Inventors: Woodard, Stanley E., Taylor, Bryant Douglas
• Primary Examiner(s): St.Cyr, Daniel
• Application Number:
  US12/253,422
• Publication Number:
  US 20090109005A1
• Time in Patent Office: 1,292 Days
• Field of Search: 235/384, 235/435, 235/439, 235/449, 235/450, 235/487, 235/492
• US Class Current: 235/449
• CPC Class Codes: G01N 27/9046 by analysing electrical signals
• CPC Class Codes: G01R 33/028 Electrodynamic magnetometers

Abstract

A wireless damage location sensing system uses a geometric-patterned wireless sensor that resonates in the presence of a time-varying magnetic field to generate a harmonic response that will experience a change when the sensor experiences a change in its geometric pattern. The sensing system also includes a magnetic field response recorder for wirelessly transmitting the time-varying magnetic field and for wirelessly detecting the harmonic response. The sensing system compares the actual harmonic response to a plurality of predetermined harmonic responses. Each predetermined harmonic response is associated with a severing of the sensor at a corresponding known location thereof so that a match between the actual harmonic response and one of the predetermined harmonic responses defines the known location of the severing that is associated therewith.

Claims

1. A wireless damage location sensing system, comprising:

an electrical conductor having first and second ends, and shaped to form a geometric pattern between said first and second ends;

said conductor in said geometric pattern defining an open-circuit that can store and transfer electrical and magnetic energy;

said conductor resonating in the presence of a time-varying magnetic field to generate a harmonic response, wherein said harmonic response changes when said conductor experiences a change in said geometric pattern;

a magnetic field response recorder (MFRR) for wirelessly transmitting said time-varying magnetic field and for wirelessly detecting said harmonic response; and

means coupled to said MFRR for comparing said harmonic response so-generated to a plurality of predetermined harmonic responses with each of said predetermined harmonic responses being associated with a severing of said conductor at a corresponding known location along said conductor such that said severing changes said geometric pattern of said conductor, wherein a match between said harmonic response and one of said predetermined harmonic responses defines said known location of said severing associated therewith.

2. A wireless damage location sensing system as in claim 1, further comprising means for operating said MFRR on a periodic basis to generate said harmonic response with periodic frequency wherein a plurality of harmonic responses are generated.

3. A wireless damage location sensing system as in claim 2, further comprising means for storing each of said harmonic responses so-generated.

4. A wireless damage location sensing system as in claim 3, further comprising means for time-stamping each of said harmonic responses so-stored.

5. A wireless damage location sensing system as in claim 1, further comprising a substrate to which said conductor is coupled.

6. A wireless damage location sensing system as in claim 5, further comprising arrangements of perforations passing through said substrate and said conductor with each of said arrangements defining one said known location for one said severing.

7. A wireless damage location sensing system as in claim 6, wherein each of said arrangements of perforations comprises a dosed geometric shape encompassing a continuous portion of said conductor.

8. A wireless damage location sensing system as in claim 1, wherein said conductor comprises a thin-film trace defining said geometric pattern, and wherein the width of said trace is selected from the group consisting of uniform and non-uniform and the spacing between adjacent portions of said trace is selected from the group consisting of uniform and non-uniform.

9. A wireless damage location sensing system as in claim 1, wherein said geometric pattern is a spiral.

10. A wireless damage location sensing system, comprising:

a substrate;

an electrical conductor coupled to said substrate, said conductor having first and second ends, and shaped to form a geometric pattern between said first and second ends;

said conductor in said geometric pattern defining an open-circuit that can store and transfer electrical and magnetic energy;

said conductor resonating in the presence of a time-varying magnetic field to generate a harmonic response, wherein said harmonic response changes when said conductor experiences a change in said geometric pattern;

a magnetic field response recorder (MFRR) for wirelessly transmitting said time-varying magnetic field on a periodic basis and for wirelessly detecting each said harmonic response generated by said conductor, wherein a plurality of harmonic responses are generated; and

means coupled to said MFRR for comparing each said harmonic response so-generated to a plurality of predetermined harmonic responses with each of said predetermined harmonic responses being associated with a severing of said conductor at a corresponding known location along said conductor such that said severing changes said geometric pattern of said conductor, wherein a match between said harmonic response and one of said predetermined harmonic responses defines said known location of said severing associated therewith.

11. A wireless damage location sensing system as in claim 10, further comprising means for storing each of said harmonic responses so-generated.

12. A wireless damage location sensing system as in claim 11, further comprising means for time-stamping each of said harmonic responses so-stored.

13. A wireless damage location sensing system as in claim 10, further comprising arrangements of perforations passing through said substrate and said conductor with each of said arrangements defining one said known location for one said severing.

14. A wireless damage location sensing system as in claim 13, wherein each of said arrangements of perforations comprises a closed geometric shape encompassing a continuous portion of said conductor.

15. A wireless damage location sensing system as in claim 10, wherein said conductor comprises a thin-film trace defining said geometric pattern, and wherein the width of said trace is selected from the group consisting of uniform and non-uniform and the spacing between adjacent portions of said trace is selected from the group consisting of uniform and non-uniform.

16. A wireless damage location sensing system as in claim 10, wherein said geometric pattern is a spiral.

17. A wireless damage location sensing system, comprising:

an electrical conductor having first and second ends, and shaped to form a geometric pattern between said first and second ends;

said conductor in said geometric pattern defining an open-circuit that can store and transfer electrical and magnetic energy;

said conductor resonating in the presence of a time-varying magnetic field to generate a harmonic response, wherein said harmonic response changes when said conductor experiences a change in said geometric pattern;

a magnetic field response recorder (MFRR) for wirelessly transmitting said time-varying magnetic field and for wirelessly detecting said harmonic response;

means coupled to said MFRR for comparing said harmonic response so-generated to a plurality of predetermined harmonic responses with each of said predetetinined harmonic responses being associated with a severing of said conductor at a corresponding known location along said conductor such that said severing changes said geometric pattern of said conductor, wherein a match between said harmonic response and one of said predetermined harmonic responses defines said known location of said severing associated therewith; and

arrangements of perforations overlaid on said geometric pattern with each of said arrangements defining one said known location for one said severing.

18. A wireless damage location sensing system as in claim 17, further comprising means for operating said MFRR on a periodic basis to generate said harmonic response with periodic frequency wherein a plurality of harmonic responses are generated.

19. A wireless damage location sensing system as in claim 18, further comprising means for storing each of said harmonic responses so-generated.

20. A wireless damage location sensing system as in claim 19, further comprising means for time-stamping each of said harmonic responses so-stored.

21. A wireless damage location sensing system as in claim 17, further comprising a substrate to which said conductor is coupled.

22. A wireless damage location sensing system as in claim 17, wherein each of said arrangements of perforations comprises a closed geometric shape encompassing a continuous portion of said conductor.

23. A wireless damage location sensing system as in claim 17, wherein said conductor comprises a thin-film trace defining said geometric pattern, and wherein the width of said trace is selected from the group consisting of uniform and non-uniform and the spacing between adjacent portions of said trace is selected from the group consisting of uniform and non-uniform.

24. A wireless damage location sensing system as in claim 17, wherein said geometric pattern is a spiral.