Elastomeric actuator devices for magnetic resonance imaging

• US 20030210811A1
• Filed: 11/08/2002
• Published: 11/13/2003
• Est. Priority Date: 05/10/2002
• Status: Active Grant

• Current Assignee: Brigham and Women's Hospital Incorporated, Massachusetts Institute of Technology
• Original Assignee: Brigham and Women's Hospital Incorporated, Massachusetts Institute of Technology
• Inventors: Hafez, Moustapha, Jolesz, Ferenc A., Weiss, Peter, Wingert, Andreas, Dubowsky, Steven, Lichter, Matthew, Kacher, Daniel F.
• Granted Patent: US 7,362,889 B2
• Time in Patent Office: Days
• US Class Current: 382/128
• CPC Class Codes: G01R 33/28 Details of apparatus provided for in groups G01R33/44 - G01R33/64

Abstract

The present invention is directed to devices and systems used in magnetic imaging environments that include an actuator device having an elastomeric dielectric film with at least two electrodes, and a frame attached to the actuator device. The frame can have a plurality of configurations including, such as, for example, at least two members that can be, but not limited to, curved beams, rods, plates, or parallel beams. These rigid members can be coupled to flexible members such as, for example, links wherein the frame provides an elastic restoring force. The frame preferably provides a linear actuation force characteristic over a displacement range. The linear actuation force characteristic is defined as ±20% and preferably 10% over a displacement range. The actuator further includes a passive element disposed between the flexible members to tune a stiffness characteristic of the actuator. The passive element can be a bi-stable element. The preferred embodiment actuator includes one or more layers of the elastomeric film integrated into the frame. The elastomeric film can be made of many elastomeric materials such as, for example, but not limited to, acrylic, silicone and latex.

Claims

1. An actuator for use in magnetic resonance imaging, comprising:

an actuator device having an elastomeric dielectric film with a first compliant electrode and a second compliant electrode, and

a frame element of a magnetic resonance imaging device attached to at least a portion of the actuator device.

2. The actuator of claim 1, wherein the elastomeric dielectric film comprises a plurality of layers of silicone.

3. The actuator of claim 1, wherein the elastomeric film comprises a plurality of layers of acrylic.

4. The actuator of claim 1, wherein the frame element further comprises a flexible member.

5. The actuator of claim 1, further comprising the frame element having a rigid member comprising one of parallel beams, curved beams, rods, and plates.

6. The actuator of claim 1, further comprising a device having a plurality of actuator stages.

7. The actuator of claim 1, further comprising an electrically resizable coil disposed on a portion of at least one of the first and the second surface of the elastomeric dielectric film.

8. The actuator of claim 1, wherein the frame element provides a linear actuation force characteristic over a displacement range.

9. A positioning device for use in magnetic resonance imaging of a region of interest having a plurality of stages, each stage of the device comprising:

an actuator device having an elastomer dielectric film with a first electrode and a second electrode;

a frame element of a magnetic resonance imaging device attached to at least a portion of the actuator device; and

an electrically resizable coil disposed on at least a portion of the actuator device to remotely control the location and focus of the region of interest.

10. The positioning device of claim 9, wherein the frame element provides a linear actuation force characteristic over a displacement range.

11. The positioning device of claim 9, wherein the frame further element comprises a rigid member coupled with a plurality of links.

12. The positioning device of claim 11, further comprising a bi-stable passive element coupled to the plurality of links.

13. The positioning device of claim 9, wherein the elastomer dielectric film comprises a plurality of layers of one of silicone and acrylic.

14. The positioning device of claim 9, wherein the frame element comprises of one of parallel beams, curved beams, rods and plates.

15. A probe for use in magnetic resonance imaging of a region of interest within a body, comprising:

an elongate shaft having a proximal end and a distal end; and

an actuator device disposed in the distal end, the actuator device having an elastomeric dielectric film with a first compliant electrode and a second compliant electrode, the actuator device further having a frame element and a variable size receiver coil disposed thereon.

16. The probe of claim 15, wherein the variable size coil is remotely controllable.

17. The probe of claim 15, further comprising of a plurality of varying sizes for insertion into and deployment within a cavity.

18. A receiver coil for use in magnetic resonance imaging of a region of interest, comprising:

an actuator device having an elastomeric dielectric film with a first compliant electrode and a second compliant electrode; and

a frame element of the magnetic resonance imaging device attached to at least a portion of the actuator device.

19. The receiver coil of claim 18, further comprising the frame element having at least one flexible member.

20. The receiver coil of claim 18, wherein the coil has a variable size that is remotely controllable.

21. The receiver coil of claim 18, wherein the coil is integrated in an intracavity probe.

22. A device to manipulate objects in a magnetic resonance imaging environment, comprising:

an actuator device having an elastomer dielectric film with a first electrode and a second electrode;

a frame element of a magnetic imaging device attached to at least a portion of the actuator device; and

an electrically resizable coil disposed on at least a portion of the elastomer dielectric film to remotely control the location and focus of the region of interest.

23. The device to manipulate objects of claim 22, wherein the frame element further comprises rigid members coupled with a plurality of links.

24. The device to manipulate objects of claim 23, further comprising a bi-stable passive element coupled to the plurality of links.

25. The device to manipulate objects of claim 22, wherein the elastomer dielectric film comprises a plurality of layers of one of silicone and acrylic.

26. The device to manipulate objects of claim 22, wherein the frame element further comprises of one of parallel beams, curved beams, rods and plates.

27. A device for applying oscillatory stress to an object for use in magnetic resonance imaging, comprising;

an actuator device having an elastomeric dielectric film with a first compliant electrode and a second compliant electrode, and

a frame element of a magnetic resonance imaging device attached to at least a portion of the actuator device.