Non-intrusive monitoring

Patent metadata

Field	Value
Publication number	US-9945692-B2
Application number	US-201414263407-A
Country	US
Kind code	B2
Filing date	Apr 28, 2014
Priority date	Apr 29, 2013
Publication date	Apr 17, 2018
Grant date	Apr 17, 2018

Abstract

Methods and apparatus for non-intrusive monitoring by sensing physical parameters such as electric and/or magnetic fields. Such apparatus and techniques may find application in a variety of fields, such as monitoring consumption of electricity, water, etc., in homes or businesses, for example, or industrial process monitoring.

First claim

What is claimed is:

1. A monitoring apparatus for monitoring flow of a fluid through a water meter, the monitoring apparatus comprising:
a first sensor apparatus configured to make a plurality of first measurements of a rotating magnetic field produced by a rotating magnetic device within the water meter when the rotating magnetic device is at a plurality of different positions relative to the first sensor apparatus;
a second sensor apparatus configured to make a plurality of second measurements of the rotating magnetic field produced by the rotating magnetic device; and
a sensor positioning apparatus configured to position the first sensor apparatus and the second sensor apparatus external to and proximate to the water meter to measure the rotating magnetic field at first and second angular positions, respectively, wherein the plurality of first measurements and the plurality of second measurements are processed to extract data representing the flow versus time.

2. The monitoring apparatus of claim 1 , wherein the sensor positioning apparatus is configured to attach to the water meter.

3. The monitoring apparatus of claim 1 , wherein the first sensor apparatus comprises a magnetic field sensor.

4. The monitoring apparatus of claim 3 , wherein the magnetic field sensor is a tunneling magnetoresistive magnetic field sensor.

5. The monitoring apparatus of claim 1 , wherein the first sensor apparatus comprises a first magnetic field sensor and the second sensor apparatus comprises a second magnetic field sensor.

6. The monitoring apparatus of claim 1 , further comprising:
a processor configured to analyze the first and second plurality of measurements to extract the data.

7. The monitoring apparatus of claim 6 , wherein the processor is configured to extract a measurement of instantaneous flow over time from the first and second plurality of measurements.

8. A non-intrusive monitoring method for monitoring flow of a fluid through a field-producing device, the method comprising:
receiving a plurality of measurements obtained by a sensor apparatus positioned proximate to the field-producing device when a rotating magnetic device within the field-producing device is at a plurality of different positions relative to the sensor apparatus; and
processing the plurality of measurements to extract data representing the flow of the fluid through the field-producing device versus time.

9. The non-intrusive monitoring method of claim 8 , wherein the data represents instantaneous flow versus time.

10. The non-intrusive monitoring method of claim 8 , wherein the plurality of measurements is a first plurality of measurements, the sensor apparatus is a first sensor apparatus and a second sensor apparatus is positioned proximate to the field-producing device, and the method further comprises:
receiving a second plurality of measurements from the second sensor apparatus; and
processing the second plurality of measurements, wherein the data is extracted by processing the first and second plurality of measurements.

11. The non-intrusive monitoring method of claim 10 , wherein the first and second sensor apparatus are positioned such that the first and second plurality of measurements are in phase quadrature.

12. The non-intrusive monitoring method of claim 10 , wherein the first and second plurality of measurements are processed to identify a direction of the flow.

13. A monitoring apparatus for monitoring flow of a fluid through a field-producing device, the monitoring apparatus comprising:
a sensor apparatus configured to measure a plurality of field strengths as a rotating magnetic device within the field-producing devices rotates relative to the sensor apparatus; and
a processor configured to extract, from the plurality of field strengths measured by the sensor apparatus at different positions of the rotating magnetic device relative to the sensor apparatus, data representing the flow of the fluid through the field-producing device versus time, the data representing flow rate transients within the field-producing device from turning on or off a fluid-consuming device that receives the fluid from the field-producing device.

14. The monitoring apparatus of claim 13 , further comprising a sensor positioning apparatus configured to position the sensor apparatus external to and proximate to the field-producing device, wherein the field-producing device is a water meter.

15. The monitoring apparatus of claim 14 , wherein the sensor positioning apparatus is configured to attach to the field-producing device.

16. The monitoring apparatus of claim 13 , wherein the field is a magnetic field and the sensor apparatus comprises a magnetic field sensor.

17. The monitoring apparatus of claim 16 , wherein the magnetic field sensor is a tunneling magnetoresistive magnetic field sensor.

18. The monitoring apparatus of claim 13 , wherein the sensor apparatus is a first sensor apparatus and the monitoring apparatus further comprises a second sensor apparatus.

19. The monitoring apparatus of claim 18 , wherein the first sensor apparatus comprises a first magnetic field sensor and the second sensor apparatus comprises a second magnetic field sensor.

20. The monitoring apparatus of claim 13 , wherein the processor is configured to extract a measurement of instantaneous flow over time.

21. The monitoring apparatus of claim 1 , wherein the sensor positioning apparatus is configured to fit over an exterior of the water meter and attach to the water meter.

22. The monitoring apparatus of claim 1 , wherein the plurality of first measurements are sampled throughout rotation of the rotating magnetic device with a sampling resolution.

23. The monitoring apparatus of claim 22 , wherein the sampling resolution is in a kHz range.

24. The monitoring apparatus of claim 1 , wherein an instantaneous frequency of the water meter is extracted from the samples of the first measurements to obtain the data representing the flow versus time.

25. The non-intrusive monitoring method of claim 8 , wherein the plurality of measurements are sampled throughout rotation of the field-producing device with a sampling resolution.

26. The non-intrusive monitoring method of claim 25 , wherein the sampling resolution is in a kHz range.

27. The non-intrusive monitoring method of claim 8 , wherein an instantaneous frequency of the water meter is extracted from the samples of the plurality of measurements to obtain the data representing the flow of the fluid through the field-producing device versus time.

Assignees

• Massachusetts Inst Technology

Inventors

• Leeb Steven B
• Paris James
• Donnal John Sebastian
• Moon Jinyeong
• Schantz Christopher

Classifications

• G01R33/098 Primary

  comprising tunnel junctions, e.g. tunnel magnetoresistance sensors · CPC title

• G01R15/207

  Constructional details independent of the type of device used · CPC title

• G01R21/08

  by using galvanomagnetic-effect devices, e.g. Hall-effect devices · CPC title

• G01D5/16 Primary

  by varying resistance · CPC title