Fetal health monitor

Patent metadata

Field	Value
Publication number	US-11207002-B2
Application number	US-201515312030-A
Country	US
Kind code	B2
Filing date	May 18, 2015
Priority date	May 19, 2014
Publication date	Dec 28, 2021
Grant date	Dec 28, 2021

Abstract

A wearable sensor apparatus is disclosed that includes a flexible substrate adapted to be coupled with a skin surface of an expectant mother. A conductor is disposed on the flexible substrate. The conductor can include micron-scale invaginations. The conductor can be capable of repeatable variation in resistance when subject to a strain. Also disclosed is a system for monitoring the health of a fetus in utero that includes a wearable sensor apparatus. The wearable sensor apparatus is configured to output a signal responsive to an electrical input. The system includes a computing system with one or more hardware processors. The computing system is programmed to implement a signal processing module configured to access the output signal from the wearable strain gauge and generate an output indicative of health of the baby in utero. The output can be based in part on the received output signal and previously stored correlations between signal data from the wearable strain gauge and observations of the system or of the mother. A user interface module can be provided and can be configured to display an output indicative of health of the baby in utero.

First claim

What is claimed is:

1. A wearable strain gauge, comprising:
a flexible substrate adapted to conformally coupled with a user's skin,
a conductor deposited on the flexible substrate, wherein the conductor comprises micron-scale invaginations, wherein adjacent micron-scale invaginations make physical contacts with each other between non-contiguous positions in the adjacent micron-scaled invaginations, wherein the physical contacts between non-contiguous positions in the adjacent micron-scaled invaginations are configured to reduce an effective resistivity of the conductor.

2. The wearable strain gauge of claim 1 , wherein the micron-scale invaginations comprise a heterogeneous topographical portion.

3. The wearable strain gauge of claim 1 , wherein the flexible substrate is configured to be mounted to an abdomen of the user.

4. A wearable strain gauge comprising a film of a highly dense and aligned one-dimensional structures.

5. The wearable strain gauge of claim 4 , wherein the highly dense and aligned one-dimensional structures are selected from the group consisting of a nanotube, a nanofiber, a nanowire and a rod.

6. The wearable strain gauge of claim 5 , wherein the nanotube is a carbon nanotube (CNT).

7. The wearable strain gauge of claim 5 , wherein the nanowire is a silicon nanowire.

8. The wearable strain gauge according to claim 4 , wherein an electrical resistance of the highly dense and aligned one-dimensional structures is about 300 kΩ.

9. The wearable strain gauge according to claim 1 , wherein the conductor further comprises nanometer-scaled invaginations.

10. A method of sensing a health condition of a pregnant mother, comprising:
coupling a wearable strain gauge according to claim 1 to an abdominal surface of the pregnant mother overlying the uterus;
directing current through the wearable strain gauge during flexing of the abdominal surface; and
measuring a characteristic of the wearable strain gauge based on a strain to generate an output for a user indicative of the health of a fetus and/or a status of pregnancy.

11. The method of claim 10 , wherein the characteristic of the wearable strain gauge is a change in the resistance of the conductor thereof.

12. The method of claim 10 , wherein movement of the surface is in response to breathing of the pregnant mother and the output indicates respiration of the pregnant mother.

13. The method of claim 10 , wherein movement of the abdominal surface is in response to motion of an underlying structure.

14. The method of claim 10 , wherein the wearable strain gauge is flexible to be secured to and conform to the abdominal surface of the pregnant mother.

15. The method of claim 10 , wherein movement of the abdominal surface is in response to movement of the fetus in utero.

16. A system for monitoring health of a fetus in utero, comprising:
a wearable strain gauge according to claim 1 configured to output a signal responsive to an electrical input;
a computing system comprising one or more hardware processors, said computing system programmed to implement:
a signal processing module configured to:
access the signal from the wearable strain gauge; and
generate an output indicative of health of the fetus in utero based in part on the signal and previously stored correlations between signal data from wearable strain gauge and observations of the system or of a mother of the fetus; and
a user interface module configured to display the output indicative of health of the fetus in utero.

17. The system of claim 16 , wherein the computing system is further programmed to implement a machine learning module configured to determine said correlations between signal data from wearable strain gauge and observations of the system or of the mother of the fetus using a machine learning algorithm.

18. The system of claim 17 , wherein the machine learning module comprises a support vector machine.

19. The system of claim 17 , wherein the machine learning module comprises unsupervised monitoring.

20. The system of claim 19 , wherein the machine learning module comprises k-nearest neighbors.

21. The system of claim 17 , wherein the machine learning module is adapted to discern uterine wall contractions from movement of a baby.

22. The system of claim 17 , wherein the machine learning module is adapted to discern smooth muscle movement or diaphragm movement from the mother of the fetus.

23. The system of claim 22 , wherein said smooth muscle movement is contractions.

24. The system of claim 22 , wherein said diaphragm movement is respiration.

25. The system of claim 16 , further comprising a physical display configured to communicate health status signals to a user.

26. The system of claim 25 , wherein the health status signals are generated and displayed in real time.

Assignees

• Univ California

Inventors

• Khine Michelle
• Pegan Jonathan
• Lee Eugene
• Bachman Mark
• Kim Joshua
• Park Sun-Jun
• Forde Gareth
• Ligon Dorsey

Classifications

• A61B5/11 Primary

  Measuring movement of the entire body or parts thereof, e.g. head or hand tremor or mobility of a limb {(A61B5/1038 takes precedence; motion detection to correct for motion artifacts in physiological signals A61B5/721)} · CPC title

• A61B5/6833

  Adhesive patches · CPC title

• A61B2562/0261

  Strain gauges · CPC title

• A61B2503/02

  Foetus · CPC title

• G16H50/20

  for computer-aided diagnosis, e.g. based on medical expert systems · CPC title