Wearable Devices with Perspiration Measurement Capabilities

Patent metadata

Field	Value
Publication number	US-2024050013-A1
Application number	US-202217988236-A
Country	US
Kind code	A1
Filing date	Nov 16, 2022
Priority date	Aug 11, 2022
Publication date	Feb 15, 2024
Grant date	—

Abstract

Embodiments are directed to devices, systems and methods for determining a perspiration metric of a user. In some embodiments, a device may include a perspiration sensor having first and second electrodes positioned on a skin-facing exterior surface of the device. Capacitance circuitry may measure a capacitance between the electrodes, which may be used to calculate the perspiration metric. In some embodiments, the device defines a cavity such that one or both of the electrodes extend at least partially into the cavity. Other embodiments include a second perspiration sensor, and measurements from the second perspiration sensor may be used in calculating the perspiration metric.

First claim

What is claimed is:

1 . A method for measuring physiological signals using an electronic device comprising a plurality of electrodes, the method comprising:
during a perspiration measurement session:
connecting a first set of electrodes of the plurality of electrodes to capacitive measurement circuitry;
performing a set of capacitance measurements using the first set of electrodes; and
calculating a perspiration metric using the set of capacitance measurements; and
during an electrocardiogram measurement;
connecting a second set of electrodes of the plurality of electrodes to electrocardiogram measurement circuitry; and
performing an electrocardiogram measurement to generate an ECG waveform; wherein:
the plurality of electrodes comprises a first electrode and a second electrode;
the first set of electrodes comprises the first electrode and the second electrode; and
the second set of electrodes comprises the first electrode.

2 . The method of claim 1 , wherein:
the second set of electrodes comprises the second electrode.

3 . The method of claim 2 , wherein:
the plurality of electrodes comprises a third electrode; and the second set of electrodes comprises the third electrode.

4 . The method of claim 1 , wherein the perspiration metric is an estimated sweat rate.

5 . The method of claim 1 , wherein the perspiration measurement session is initiated while the electronic device is tracking an exercise session.

6 . The method of claim 5 , wherein the perspiration measurement session is initiated automatically in response to the electronic device tracking the exercise session.

7 . A device for calculating a perspiration metric of a user, comprising:
a housing having an exterior surface; a perspiration sensor comprising:
a first electrode; and
a second electrode; and
a processer configured to calculate the perspiration metric using the perspiration sensor; wherein:
the exterior surface of the housing defines a cavity; and
the first electrode extends at least partially into the cavity.

8 . The device of claim 7 , wherein:
the second electrode extends at least partially into the cavity.

9 . The device of claim 7 , wherein:
a portion of the first electrode is positioned outside of the cavity.

10 . The device of claim 7 , wherein:
the exterior surface comprises a first region surrounding a second region; and a first portion of the second region is recessed relative to the second region to define the cavity.

11 . The device of claim 10 , wherein:
a second portion of the second region protrudes past the first region.

12 . The device of claim 10 , wherein:
the cavity has an annular shape.

13 . The device of claim 10 , further comprising:
an optical sensor comprising a set of windows; wherein the set of windows is positioned in the second region.

14 . The device of claim 7 , wherein:
the perspiration sensor is a first perspiration sensor; and the device comprises a second perspiration sensor.

15 . The device of claim 7 , wherein:
the perspiration sensor comprises capacitance measurement circuitry configured to measure a capacitance between the first electrode and the second electrode.

16 . A device for calculating a perspiration metric of a user, comprising:
a housing having an exterior surface that defines a first cavity; a first perspiration sensor comprising:
a first electrode defining a first portion of the exterior surface; and
a second electrode defining a second portion of the exterior surface;
a second perspiration sensor contained within the first cavity; and a processer configured to calculate the perspiration metric using both the first perspiration sensor and the second perspiration sensor.

17 . The device of claim 16 , wherein:
the housing defines a second cavity; and the first electrode extends at least partially into the second cavity.

18 . The device of claim 17 , wherein:
the second cavity encircles the first cavity.

19 . The device of claim 16 , wherein:
the first cavity is positioned between at least a portion of the first electrode and at least a portion of the second electrode.

20 . The device of claim 16 , wherein:
the first cavity is positioned closer to a center of the exterior surface of the housing relative to the first electrode.

Assignees

• Apple Inc

Inventors

• Kim Sung H
• Ha Hyunsoo
• Ahmadi Muhammad
• Shi Justin S

Classifications

• A61B5/4266

  sweat secretion · CPC title

• A61B5/28 Primary

  for electrocardiography [ECG] · CPC title

• A61B5/277

  Capacitive electrodes · CPC title

• A61B5/256

  Wearable electrodes, e.g. having straps or bands · CPC title

• A61B5/282

  Holders for multiple electrodes (for introduction into the body A61B5/287) · CPC title