Frame-suspended magnetoelastic resonators

Patent metadata

Field	Value
Publication number	US-10557898-B2
Application number	US-201515113178-A
Country	US
Kind code	B2
Filing date	Jan 23, 2015
Priority date	Jan 24, 2014
Publication date	Feb 11, 2020
Grant date	Feb 11, 2020

Abstract

A magnetoelastic tag includes a frame-suspended magnetoelastic resonator that combines a strong resonant response with a relatively small resonator, enabling magnetoelastic sensor use in a variety of inconspicuous applications and/or small packages. The resonator is suspended with respect to a substrate, which reduces, minimizes, or eliminates interaction between the substrate and resonator. Signal strength is thereby enhanced, thereby allowing miniaturization while maintaining a measurable response to the interrogation field. The resonator can have a hexagonal shape and/or be suspended at particular locations about its perimeter to promote signal generation in a direction different from that of the interrogation field. A sensor can include one or more frame-suspended resonators, which can be arranged in an array, stacked, or randomly where a plurality of resonators is employed.

First claim

The invention claimed is:

1. A magnetoelastic tag, comprising:
a resonator comprising a magnetoelastic layer; and
a resonator frame coupled with the resonator and configured to support the resonator in spaced relation with respect to a substrate, wherein the resonator has a shape with multiple non-orthogonal axes of symmetry, and
wherein the resonator is suspended from the frame along an outer perimeter of the resonator by one or more couplings, each coupling extending from an edge of the frame to the outer perimeter of the resonator and attaching the resonator to the frame.

2. A magnetoelastic tag as defined in claim 1 , wherein said shape has rotational symmetry.

3. A magnetoelastic tag as defined in claim 1 , wherein said shape is a hexagon.

4. A magnetoelastic tag as defined in claim 1 , wherein the resonator and resonator frame are monolithic and comprise the same magnetoelastic layer.

5. A magnetoelastic tag as defined in claim 1 , wherein the resonator frame circumscribes the resonator so that a gap is defined between an edge of the resonator and the frame.

6. A magnetoelastic tag as defined in claim 1 , wherein at least a portion of the magnetoelastic tag is curved out of plane so that only one or more edges of the resonator frame contact the substrate.

7. A magnetoelastic tag as defined in claim 1 , wherein the resonator is suspended within the frame.

8. A magnetoelastic sensor system comprising the magnetoelastic tag of claim 1 , a transmit coil, and a receive coil.

9. The magnetoelastic sensor system of claim 8 , wherein the transmit coil is arranged in an orientation different than an orientation of the receive coil.

10. A magnetoelastic sensor comprising a plurality of magnetoelastic tags as defined in claim 1 .

11. A magnetoelastic sensor as defined in claim 10 , wherein each one of the magnetoelastic tags includes an individual resonator attached to an individual frame.

12. A magnetoelastic sensor as defined in claim 10 , wherein the resonators of the plurality of magnetoelastic tags are arranged in an array.

13. A magnetoelastic sensor as defined in claim 10 , wherein at least one of the resonators of the plurality of magnetoelastic tags has an orientation different from another one of the resonators of the plurality of magnetoelastic tags.

14. A magnetoelastic sensor as defined in claim 10 , wherein at least one of the resonators of the plurality of magnetoelastic tags is stacked with at least one other resonator of the plurality of magnetoelastic tags.

15. A magnetoelastic sensor as defined in claim 10 , wherein each resonator of the plurality of magnetoelastic tags has an individual characteristic electromagnetic response to an applied magnetic field, and the plurality of magnetoelastic tags has an electromagnetic response to the same applied magnetic field that is equal to or greater than a sum of the individual electromagnetic responses.

16. A magnetoelastic sensor as defined in claim 10 , wherein at least one resonator of the plurality of magnetoelastic tags has one or both of the following different from another resonator of the plurality of magnetoelastic tags: a resonant frequency and a size.

17. A magnetoelastic sensor as defined in claim 10 , wherein the resonator of each one of the magnetoelastic tags is suspended within the frame of the corresponding one of the magnetoelastic tags.

18. A magnetoelastic sensor as defined in claim 10 , wherein the resonator and frame of each one of the magnetoelastic tags are monolithic and comprise the same magnetoelastic layer.

19. A magnetoelastic tag as defined in claim 1 , wherein the resonator is suspended from the frame only along the outer perimeter of the resonator.

20. A magnetoelastic tag as defined in claim 1 , wherein each coupling is located along one of the axes of symmetry.

Assignees

• Univ Michigan Regents

Inventors

• Gianchandani Yogesh
• Tang Jun
• Green Scott

Classifications

• G01R33/063

  Magneto-impedance sensors; Nanocristallin sensors · CPC title

• G01R33/18 Primary

  Measuring magnetostrictive properties · CPC title

• G01R33/0385

  in relation with magnetic force measurements (magnetic force microscopes G01Q60/50) · CPC title

• G01L1/125

  by using magnetostrictive means (magnetostrictive sensors H10N35/101) · CPC title

• G01R33/04

  using the flux-gate principle · CPC title