Wearable electronic device and method of operating the same
A wearable electronic device is provided. The wearable electronic device includes at least one first thermistor arranged in different heat generation positions in the wearable electronic device and configured to detect a temperature change of internal elements of the wearable electronic device, a temperature sensor configured to calculate a body temperature of a user based on the temperature change of the internal elements and a skin temperature trend of the user, and at least one processor configured to determine whether an internal temperature by the internal elements in the wearable electronic device is within a reference temperature range that does not have an influence on a calculation of the body temperature, based on a measured value of the at least one first thermistor, determine a user state index (UI) indicating whether the user is in a state in which the body temperature is measurable, when the internal temperature is determined to be within the reference temperature range, and measure the body temperature by adjusting a body temperature measurement period based on the UI.
1 . A wearable electronic device comprising:
at least one first thermistor arranged in different heat generation positions in the wearable electronic device and configured to detect a temperature change of internal elements of the wearable electronic device;
a temperature sensor configured to calculate a body temperature of a user based on the temperature change of the internal elements and a skin temperature trend of the user; and
at least one processor, comprising processing circuitry, individually and/or collectively configured to:
determine whether an internal temperature by the internal elements in the wearable electronic device is within a reference temperature range that does not have an influence on a calculation of the body temperature, based on a measured value of the at least one first thermistor,
determine a user state index (UI) indicating whether the user is in a state in which the body temperature is measurable, when the internal temperature is determined to be within the reference temperature range, and
measure the body temperature during a body temperature measurement period that is adjusted based on the UI, wherein the body temperature measurement period is increased based on decrease in the UI and the body temperature measurement period is decreased based on increase in the UI,
wherein the UI is determined based on a combination of at least two of user state variables, including the skin temperature trend of user, a user motion, and a heart rate variation.
2 . The wearable electronic device of claim 1 , further comprising a contact sensor configured to detect whether the user is in contact with the wearable electronic device,
wherein the at least one processor is further configured to determine whether the internal temperature is within the reference temperature range based on the measured value of the at least one first thermistor, when it is determined by the contact sensor that the user wears the wearable electronic device.
3 . The wearable electronic device of claim 1 , wherein the internal elements comprise at least one of an application processor (AP), a battery, or a communication processor (CP).
4 . The wearable electronic device of claim 1 , wherein the at least one processor is further configured to:
calculate a representative value of temperatures of the internal elements based on the measured value of the at least one first thermistor, and
determine whether the representative value is within the reference temperature range.
5 . The wearable electronic device of claim 4 , wherein the at least one processor is further configured to assign different weights for each measured value of the at least one first thermistor and calculate the representative value.
6 . The wearable electronic device of claim 4 , wherein the at least one processor is further configured to:
remeasure a value of the at least one first thermistor after a reconfirmation time used for a temperature decrease for each of the temperatures of the internal elements elapses, when the representative value is determined to be out of the reference temperature range, and
determine whether the remeasured value of the first thermistor is within the reference temperature range.
7 . The wearable electronic device of claim 1 , further comprising at least one of a motion sensor configured to detect a motion of the user, a photoplethysmogram (PPG) sensor configured to detect a heart rate of the user, or a second thermistor configured to estimate the skin temperature trend of the user outside the wearable electronic device,
wherein the at least one processor is further configured to:
estimate the skin temperature trend of the user wearing the wearable electronic device using a measured value of the second thermistor, when the internal temperature is determined to be within the reference temperature range, and
determine the UI based on the user state variables, including the skin temperature trend of user, a user motion, and a heart rate variation.
8 . The wearable electronic device of claim 7 , wherein the at least one processor is further configured to:
determine whether the user performs a first exercise, based on a degree of motion of the user quantified based on a value of a magnitude of the motion sensor,
determine a stable state of the user based on the variation in the heart rate of the user, the variation corresponding to a difference between the heart rate of the user and a resting heart rate of the user,
determine whether the user performs a second exercise, based on the skin temperature trend, and
determine the UI based on whether the user performs the first exercise, whether the user performs the second exercise, and the stable state of the user.
9 . The wearable electronic device of claim 1 , wherein the at least one processor is further configured to:
reduce the body temperature measurement period when the UI is similar to an index indicating an unstable state, and
increase the body temperature measurement period when the UI is similar to an index indicating a stable state.
10 . The wearable electronic device of claim 1 , further comprising a second thermistor configured to estimate the skin temperature trend of the user outside the wearable electronic device,
wherein the at least one processor is configured to correct a body temperature of the user acquired based on the body temperature measurement period using the temperature sensor, based on a measured value of the second thermistor.
11 . A method of operating a wearable electronic device, the method comprising:
determining whether the wearable electronic device is worn;
determining whether an internal temperature by internal elements of the wearable electronic device is within a reference temperature range that does not have an influence on a measurement of a body temperature of a user, based on whether the wearable electronic device is worn;
determining a user state index (UI) indicating whether the user is in a state in which the body temperature is measurable, when the internal temperature is determined to be within the reference temperature range; and
measuring the body temperature during a body temperature measurement period that is adjusted based on the UI, wherein the body temperature measurement period is increased based on decrease in the UI and the body temperature measurement period is decreased based on increase in the UI,
wherein the UI is determined based on a combination of at least two of user state variables, including a skin temperature trend, a user motion, and a heart rate variation.
12 . The method of claim 11 ,
wherein the wearable electronic device comprises at least one first thermistor arranged in different heat generation positions in the wearable electronic device and configured to detect a temperature change of the internal elements, and
wherein the determining of whether the internal temperature is within the reference temperature range comprises determining whether the internal temperature by the internal elements is within the reference temperature range, by a measured value of the at least one first thermistor, based on whether the wearable electronic device is worn.
13 . The method of claim 12 , wherein the internal elements comprise at least one of an application processor (AP), a battery, or a communication processor (CP).
14 . The method of claim 13 , wherein the determining of whether the internal temperature is within the reference temperature range comprises:
calculating a representative value of temperatures of the internal elements based on the measured value of the at least one first thermistor; and
determining whether the representative value is within the reference temperature range.
15 . The method of claim 14 , wherein the determining of whether the representative value is within the reference temperature range comprises:
remeasuring a value of the at least one first thermistor after a reconfirmation time used for a temperature decrease for each of the temperatures of the internal elements elapses, when the representative value is determined to be out of the reference temperature range; and
determining whether the remeasured value is within the reference temperature range.
16 . The method of claim 11 ,
wherein the wearable electronic device further comprises at least one of a second thermistor configured to estimate a skin temperature trend of the user outside the wearable electronic device, a motion sensor configured to detect a motion of the user, or a photoplethysmogram (PPG) sensor configured to detect a heart rate of the user, and
wherein the determining of the UI comprises:
estimating the skin temperature trend of the user wearing the wearable electronic device using a measured value of the second thermistor, when the internal temperature is determined to be within the reference temperature range, and
determining the UI based on the user state variables, including the skin temperature trend of user, a user motion, and a heart rate variation.
17 . The method of claim 16 , wherein the determining of the UI comprises:
determining whether the user performs a first exercise, based on a degree of motion of the user quantified based on a value of a magnitude of the motion sensor;
determining a stable state of the user based on the variation in the heart rate of the user, the variation corresponding to a difference between the heart rate of the user and a resting heart rate of the user;
determining whether the user performs a second exercise based on the skin temperature trend; and
determining the UI based on at least one of whether the user performs the first exercise, whether the user performs the second exercise, or the stable state of the user.
18 . The method of claim 11 , wherein the measuring of the body temperature comprises:
reducing the body temperature measurement period when the UI is similar to an index indicating an unstable state; and
increasing the body temperature measurement period when the UI is similar to an index indicating a stable state.
19 . The method of claim 11 ,
wherein the wearable electronic device further comprises a second thermistor configured to estimate a skin temperature trend of the user outside the wearable electronic device, and
wherein the measuring of the body temperature comprises:
acquiring the body temperature of the user based on the body temperature measurement period using a temperature sensor, and
correcting the acquired body temperature based on a measured value of the second thermistor.
20 . The method of claim 15 , further comprising:
assigning different weights for each measured value of the at least one first thermistor and calculating the representative value.