Wireless power transfer and communications

• US 9,962,085 B2
• Filed: 07/30/2015
• Issued: 05/08/2018
• Est. Priority Date: 07/30/2014
• Status: Active Grant

• Current Assignee: Alfred E. Mann Foundation For Scientific Research
• Original Assignee: Alfred E. Mann Foundation For Scientific Research
• Inventors: Griffith, Glen A.
• Primary Examiner(s): KAPLAN, HAL IRA
• Application Number:
  US14/814,447
• Publication Number:
  US 20160036244A1
• Time in Patent Office: 1,013 Days
• Field of Search: 307104, 320108
• CPC Class Codes: A61B 2560/0219 of externally powered implanted units
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61F 2/54 Artificial arms or hands or parts thereof
• CPC Class Codes: A61F 2/72 Bioelectric control, e.g. myoelectric
• CPC Class Codes: A61F 2002/701 operated by electrically controlled means, e.g. solenoids or torque motors
• CPC Class Codes: A61F 2002/704 computer-controlled, e.g. robotic control
• CPC Class Codes: A61F 2002/705 Electromagnetic data transfer
• CPC Class Codes: A61F 2002/7615 Measuring means
• CPC Class Codes: A61N 1/37229 Shape or location of the implanted or external antenna
• CPC Class Codes: A61N 1/3787 from an external energy source
• CPC Class Codes: H02J 2310/23 The load being a medical device, a medical implant, or a life supporting device
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/40 using two or more transmitting or receiving devices H02J50/50 takes precedence
• CPC Class Codes: H02J 50/70 involving the reduction of electric, magnetic or electromagnetic leakage fields
• CPC Class Codes: H04B 5/24 Inductive coupling
• CPC Class Codes: H04B 5/266 One coil at each side, e.g. with primary and secondary coils
• CPC Class Codes: H04B 5/72 for local intradevice communication
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

An inductive wireless power transfer and communication system includes an electrostatic shield for one of the coils. The electrostatic shield is inductively coupled with the coil and is configured as an open circuit. A signal processing element or elements, especially a modulator or a demodulator, are connected across the electrical discontinuity in the electrostatic shield. Because the electrostatic shield is inductively coupled to the coil, the modulator or demodulator can operate on the signal on the coil.

Claims

1. A wireless power transfer and communication system comprising:

a first coil;

an electrostatic shield for the first coil, the electrostatic shield having a gap extending the axial length of the electrostatic shield, wherein the electrostatic shield is inductively coupled to the first coil;

a first signal processor coupled across the gap of the electrostatic shield;

a second coil, the second coil being inductively coupled to the first coil;

a second signal processor coupled to the second coil; and

a coil driver coupled to the first coil and configured to generate a carrier signal on the first coil.

2. The system of claim 1 wherein the first signal processor and the second signal processor communicate through modulation of the carrier signal.

3. The system of claim 1 wherein the first signal processor comprises a modulator configured to modulate data onto the carrier signal and the second signal processor comprises a demodulator configured to demodulate the carrier signal and output the data.

4. The system of claim 1 wherein the second signal processor comprises a modulator configured to modulate data onto the carrier signal and the first signal processor comprises a demodulator configured to demodulate the carrier signal and output the data.

5. The system of claim 1 wherein the electrostatic shield is inductively coupled to the first coil as a single turn secondary winding.

6. The system of claim 1 wherein the gap prevents the electrostatic shield from acting as a shorted turn.

7. The system of claim 1 wherein the electrostatic shield is adjacent to the outer surface of the first coil, surrounds the first coil circumferentially, and is open on both ends.

8. The system of claim 1 wherein the electrostatic shield is adjacent to the inner surface of the first coil, extends around the inner surface of the first coil circumferentially, and is open on both ends.

9. The system of claim 1 wherein the electrostatic shield has an outer portion and an inner portion, the outer portion is adjacent to the outer surface of the first coil and surrounds the first coil circumferentially, the inner portion is adjacent to the inner surface of the first coil and extends around the inner surface of the first coil circumferentially, and both the outer portion and the inner portion are open on both ends.

10. The system of claim 9 wherein the gap extends the axial length of both the outer portion and the inner portion of the electrostatic shield.

11. The apparatus of claim 1 wherein:

the electrostatic shield has a cylindrical or truncated conical structure that is open on both ends and which is coaxial with the first coil; and

the gap extends from one open end of the electrostatic shield to the other.

12. The system of claim 1 wherein a center tap of the electrostatic shield is connected to ground.

13. The system of claim 1 wherein the first coil and the electrostatic shield are configured to fit over a limb of a patient.

14. The system of claim 13 wherein the limb is a residual portion of an amputated limb.

15. The system of claim 13 wherein the electrostatic shield is positioned to reduce parasitic variations introduced on the first coil by the limb.

16. The system of claim 13 further comprising:

an implantable biological sensor providing sensor data to the second signal processor, wherein the second signal processor is configured to modulate the carrier signal with the sensor data, and the first signal processor demodulates the carrier signal and outputs received sensor data.

17. The system of claim 16 further comprising:

a prosthetic device with a prosthetic controller, wherein the prosthetic controller is coupled to the first signal processor and receives the received sensor data and generates control signals to actuate the prosthetic device.

18. A method of communicating between a first coil and a second coil, the first coil having an electrostatic shield, the first coil being inductively coupled with the electrostatic shield, the first coil being inductively coupled with the second coil, comprising:

generating a carrier signal on the first coil;

receiving an input data signal;

modulating the carrier signal with the data from the input data signal on the second coil;

demodulating the carrier signal on the electrostatic shield; and

outputting an output data signal comprising the data demodulated from the carrier signal.

19. The method of claim 18 wherein modulating the carrier signal on the second coil is changing the impedance presented to the first coil by the second coil.

20. The method of claim 18 wherein the input data signal is sensor data received from a biological sensor.

21. The method of claim 18 further comprising:

actuating a prosthetic device based on the output data signal.

22. A method of communicating between a first coil and a second coil, the first coil having an electrostatic shield, the first coil being inductively coupled with the electrostatic shield, the first coil being inductively coupled with the second coil, comprising:

generating a carrier signal on the first coil;

receiving an input data signal;

modulating the carrier signal with the data from the input data signal on the electrostatic shield;

demodulating the carrier signal on the second coil; and

outputting an output data signal comprising the data demodulated from the carrier signal.

23. The method of claim 22 wherein modulating the carrier signal on the electrostatic shield is changing the impedance presented to the first coil by the electrostatic shield.

24. A wireless power transfer and communication apparatus comprising:

a first coil;

a coil driver circuit, the coil driver circuit being coupled to the first coil and configured to generate a carrier signal on the first coil;

an electrostatic shield for the first coil, the electrostatic shield having a gap extending the axial length of the electrostatic shield, wherein the electrostatic shield is inductively coupled to the first coil; and

a demodulator connected across the gap of the electrostatic shield, wherein the demodulator demodulates the carrier signal.

25. The apparatus of claim 24 wherein the first coil inductively couples to a second coil, and wherein the carrier signal is modulated by changing the impedance of the second coil.

26. The apparatus of claim 24 further comprising:

an implantable biological sensor providing sensor data to a modulator, wherein the modulator is coupled to a second coil, the second coil being inductively coupled to the first coil, and wherein the modulator is configured to modulate the carrier signal with the sensor data.

27. The apparatus of claim 24 further comprising:

a prosthetic device with a prosthetic controller, wherein the prosthetic controller is coupled to the demodulator and generates control signals to actuate the prosthetic device based on the demodulated carrier signal.

28. The apparatus of claim 24 wherein the electrostatic shield is inductively coupled to the first coil as a single turn secondary coil.

29. The apparatus of claim 24 wherein the gap prevents the electrostatic shield from acting as a shorted turn.

30. The apparatus of claim 24 wherein:

the electrostatic shield has a cylindrical or truncated conical structure that is open on both ends and which is coaxial with the first coil; and

wherein the gap extends from one open end of the electrostatic shield to the other.

31. The apparatus of claim 24 wherein the electrostatic shield is adjacent to the outer surface of the first coil, surrounds the first coil circumferentially and is open on both ends.

32. The apparatus of claim 31 wherein the gap extends from one open end of the electrostatic shield to the other.

33. The apparatus of claim 24 wherein the electrostatic shield is adjacent to the inner surface of the first coil, extends around the inner surface of the first coil circumferentially, and is open on both ends.

34. The apparatus of claim 33 wherein the gap extends from one open end of the electrostatic shield to the other.

35. The apparatus of claim 24 wherein a center tap of the electrostatic shield is connected to ground.

36. The apparatus of claim 24 wherein the first coil and the electrostatic shield are configured to fit over a limb of a patient.

37. The apparatus of claim 36 wherein the limb is a residual portion of an amputated limb.

38. A wireless power transfer and communication apparatus comprising:

a first coil;

a coil driver circuit, the coil driver circuit being coupled to the first coil and configured to generate a carrier signal on the first coil;

an electrostatic shield for the first coil, the electrostatic shield having a gap extending the axial length of the electrostatic shield, wherein the electrostatic shield is inductively coupled to the first coil; and

a modulator connected across the gap of the electrostatic shield, wherein the modulator modulates the carrier signal.

39. The apparatus of claim 38 wherein the electrostatic shield is inductively coupled to the first coil as a single turn secondary coil.

40. The apparatus of claim 38 wherein the gap prevents the electrostatic shield from acting as a shorted turn.

41. The apparatus of claim 38 wherein:

the electrostatic shield has a cylindrical or truncated conical structure that is open on both ends and which is coaxial with the first coil; and

wherein the gap extends from one open end of the electrostatic shield to the other.

42. The apparatus of claim 38 wherein the electrostatic shield is adjacent to the outer surface of the first coil, surrounds the first coil circumferentially and is open on both ends.

43. The apparatus of claim 42 wherein the gap extends from one open end of the electrostatic shield to the other.

44. The apparatus of claim 38 wherein the electrostatic shield is adjacent to the inner surface of the first coil, extends around the inner surface of the first coil circumferentially, and is open on both ends.

45. The apparatus of claim 44 wherein the gap extends from one open end of the electrostatic shield to the other.

46. The apparatus of claim 38 wherein a center tap of the electrostatic shield is connected to ground.

47. The apparatus of claim 38 wherein the first coil and the electrostatic shield are configured to fit over a limb of a patient.

48. The apparatus of claim 47 wherein the limb is a residual portion of an amputated limb.