Multi-ferroic structural health monitoring systems

• US 8,726,737 B2
• Filed: 02/12/2013
• Issued: 05/20/2014
• Est. Priority Date: 09/16/2010
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Georgeson, Gary E., Miller, Robert James
• Primary Examiner(s): Noori, Max
• Application Number:
  US13/764,866
• Publication Number:
  US 20130147636A1
• Time in Patent Office: 462 Days
• Field of Search: 737/60, 737/77, 737/86, 737/79
• US Class Current: 73/779
• CPC Class Codes: B29C 65/4855 characterised by their physical properties, e.g. being electrically-conductive
• CPC Class Codes: B29C 65/4875 being spherical, e.g. particles or powders
• CPC Class Codes: B29C 65/489 being metals
• CPC Class Codes: B29C 65/8284 by the use of magnetic means
• CPC Class Codes: B29C 66/721 Fibre-reinforced materials B29C66/729 takes precedence
• CPC Class Codes: B29K 2995/0008 Magnetic or paramagnetic
• CPC Class Codes: B29L 2031/3076 Aircrafts blades, propellers B29L2031/08
• CPC Class Codes: B64D 2045/0085 Devices for aircraft health monitoring, e.g. monitoring flutter or vibration
• CPC Class Codes: B64F 5/60 Testing or inspecting aircraft components or systems
• CPC Class Codes: G01B 7/24 using change in magnetic properties
• CPC Class Codes: G01L 1/12 by measuring variations in the magnetic properties of materials resulting from the application of stress
• CPC Class Codes: G01L 1/125 by using magnetostrictive means magnetostrictive sensors H10N35/101
• CPC Class Codes: G01M 5/0033 by determining damage, crack or wear
• CPC Class Codes: G01M 5/0066 by exciting or detecting vibration or acceleration vibration testing of structures G01M7/00
• CPC Class Codes: G01M 5/0083 by measuring variation of impedance, e.g. resistance, capacitance, induction
• CPC Class Codes: G01M 5/0091 by using electromagnetic excitation or detection
• CPC Class Codes: G01R 33/098 comprising tunnel junctions, e.g. tunnel magnetoresistance sensors
• CPC Class Codes: G01R 33/1269 of molecules labeled with magnetic beads magnetic particles for bio assay G01N33/54326
• CPC Class Codes: G08C 17/02 using a radio link
• CPC Class Codes: Y10T 428/31504 Composite [nonstructural laminate]

Abstract

A structural health monitoring system for multiple layer structures includes a plurality of strain-sensitive magnetic particles dispersed within a bonding area between at least two individual layers, at least one multiferroic sensor dispersed on a surface of the multiple layer structure, proximate to an area of the structure to be monitored, the at least one multiferroic sensor capable of monitoring strains experienced by the strain-sensitive magnetic particles, and analyzing changes in the strains experienced by said strain-sensitive magnetic particles that may indicate damage or degradation in the structure, and a controller configured for periodic interrogation of the at least one multiferroic sensor.

Claims

1. A structural health monitoring system for multiple layer structures comprising:

a plurality of strain-sensitive magnetic particles dispersed within a bonding area between at least a first surface of a first layer and a second layer of a multiple layer structure;

at least one multiferroic sensor dispersed on a second surface of the first layer of the multiple layer structure, proximate to an area of the structure to be monitored, said at least one multiferroic sensor capable of monitoring strains experienced by said strain-sensitive magnetic particles, and analyzing changes in the strains experienced by said strain-sensitive magnetic particles that may indicate damage or degradation in the structure; and

a controller configured for periodic interrogation of the at least one multiferroic sensor.

2. The structural health monitoring system of claim 1 wherein said plurality of strain-sensitive magnetic particles are substantially evenly dispersed within the bonding area.

3. The structural health monitoring system of claim 1 wherein said multiferroic sensors are dispersed on the surface of the multiple layer structure to provide overlapping coverage of said plurality of strain-sensitive magnetic particles.

4. The structural health monitoring system of claim 1 wherein said at least one multiferroic sensor is configured to sense at least one of a magnetization level of said magnetic particles and a magnetic permeability of said magnetic particles.

5. The structural health system of claim 1 wherein said at least one multiferroic sensor comprises an RFID communications capability for responding to said controller.

6. The structural health monitoring system of claim 1 wherein each said multiferroic sensor comprises:

a data processing capability;

a memory;

an RFID communications capability; and

a multiferroic sensor element, each said multiferroic sensor capable of storing information indicative of the environment sensed by said sensor element, and communicating such information to said controller through RFID interrogation.

7. The structural health monitoring system of claim 6 wherein each said multiferroic sensor comprises at least one of a battery and an energy harvesting device.

8. The structural health monitoring system of claim 1 wherein said plurality of strain-sensitive magnetic particles comprise at least one of a magnetostrictive metal, a magnetostrictive alloy, and a magnetostrictive ferrite material.

9. The structural health monitoring system of claim 1 wherein said plurality of strain-sensitive magnetic particles comprise a high aspect ratio shape for coupling to the structure and increased sensitivity to strain in the structure.

10. The structural health monitoring system of claim 1 wherein said plurality of strain-sensitive magnetic particles comprise nonmagnetic fibers having a coating of magnetostrictive material thereon.

11. The structural health monitoring system of claim 1 further comprising a flexible appliqué

for application to the surface of the structure, said flexible appliqué

comprising said at least one multiferroic sensor fabricated as a thin film device attached thereto.

12. A structural health monitoring system for multiple layer structures comprising:

a plurality of strain-sensitive magnetic particles dispersed within a bonding area between a surface of a first layer of a structure and a second layer of the structure;

at least one multiferroic sensor dispersed on an opposing surface of the first layer, proximate to an area of the structure to be monitored; and

a controller configured to periodically interrogate the at least one multiferroic sensor to monitor strains experienced by said plurality of strain-sensitive magnetic particles, and analyze changes in the strains experienced by said plurality of strain-sensitive magnetic particles to determine an amount of damage or degradation in the structure.

13. The structural health monitoring system of claim 12 wherein said plurality of strain-sensitive magnetic particles are substantially evenly dispersed within the bonding area, and said at least one multiferroic sensor is dispersed on the opposing surface of the first layer to provide overlapping coverage of said plurality of strain-sensitive magnetic particles.

14. The structural health monitoring system of claim 13 wherein said at least one multiferroic sensor is configured to sense at least one of a magnetization level of said plurality of strain-sensitive magnetic particles and a magnetic permeability of said plurality of strain-sensitive magnetic particles.

15. The structural health monitoring system of claim 12 wherein said at least one multiferroic sensor comprises:

a data processing capability;

a memory;

an RFID communications capability; and

a multiferroic sensor element configured detect an environment, store information indicative of the environment in said memory, and communicate the information to said controller through said RFID communications capability.

16. The structural health monitoring system of Claim 15 wherein said multiferroic sensor element comprises at least one of a battery and an energy harvesting device.

17. The structural health monitoring system of claim 12 wherein said plurality of strain-sensitive magnetic particles comprise at least one of a magnetostrictive metal, a magnetostrictive alloy, and a magnetostrictive ferrite material.

18. The structural health monitoring system of claim 12 wherein said plurality of strain-sensitive magnetic particles comprise a high aspect ratio shape for coupling to the structure and increased sensitivity to strain in the structure.

19. The structural health monitoring system of claim 12 wherein said plurality of strain-sensitive magnetic particles comprise nonmagnetic fibers having a coating of magnetostrictive material thereon.

20. The structural health monitoring system of claim 12 further comprising a flexible appliqué

for application to the structure, said flexible appliqué

comprising said at least one multiferroic sensor fabricated as a thin film device attached thereto.