Apparatus and method for estimating bio-information

1 . An apparatus for estimating blood pressure information, the apparatus comprising:

a sensor part comprising:

a pulse wave sensor comprising a light source and a detector, the pulse wave sensor configured to measure a pulse wave signal from a body part of a user based on the light source emitting light toward to the body part of the user, and the detector detecting the emitted light reflected by the body part of the user; and

a contact pressure sensor configured to measure contact pressure values corresponding to a contact pressure of the body part of the user applied to the sensor part; and

a processor configured to:

cause the pulse wave sensor to measure the pulse wave signal at multiple measurement times during a period of time;

output guide information on the contact pressure to be applied by the body part of the user to the contact pressure sensor for the period of time while the pulse wave signal is measured by the pulse wave sensor, the guide information instructing the user to gradually change the contact pressure;

cause the contact pressure sensor to measure the contact pressure values during the period of time;

extract direct current (DC) component values from the pulse wave signal using a low-pass filter;

generate a graph based on the contact pressure values and the DC component values by plotting a DC component value with respect to a contact pressure value at each of the multiple measurement times;

obtain one or more features based on the generated graph by performing curve fitting for the generated graph using a fitting model and obtaining a coefficient of the curve fitting as the one or more features, wherein the DC component values of the pulse wave signal increase as the contact pressure values increase;

estimate the blood pressure information based on the obtained one or more features, and

output a blood pressure notification based on the estimated blood pressure information.

2 . The apparatus of claim 1 , wherein the coefficient comprises any one or any combination of a maximum slope value, a contact pressure value at a maximum slope point, or a maximum amplitude value from the graph.

3 . An apparatus for estimating blood pressure information, the apparatus comprising:

a memory storing one or more instructions; and

a processor configured to execute the one or more instructions to:

obtain, at multiple measurement times in a period of time, from a pulse wave sensor included in a sensor part, a pulse wave signal representing a vital function of a user by emitting, by a light source of the pulse wave sensor, light toward to a body part of the user, and a detector of the pulse wave sensor, detecting the emitted light reflected by the body part of the user;

output guide information on a contact pressure to be applied by the body part of the user to a contact pressure sensor, included in the sensor part, for the period of time while the pulse wave signal is measured by the pulse wave sensor, the guide information instructing the user to gradually change the contact pressure;

obtain, from the contact pressure sensor, contact pressure values corresponding to the contact pressure applied by the body part of the user to the sensor part during the period of time in an increasing or decreasing manner,

extract direct current (DC) component values from the pulse wave signal using a low-pass filter;

generate a graph based on the contact pressure values and the DC component values by plotting a DC component value with respect to a contact pressure value at each of the multiple measurement times;

obtain one or more features based on the generated graph by performing curve fitting for the graph using a fitting model and obtaining a coefficient of the curve fitting as the one or more features;

estimate the blood pressure information based on the obtained one or more features; and

output a blood pressure notification based on the estimated blood pressure information.

4 . The apparatus of claim 3 , wherein the processor is further configured to:

obtain an oscillometric envelope based on an amplitude of the pulse wave signal and the contact pressure values, and

estimate the blood pressure information further based on a center of mass of a phase of contact pressure of the obtained oscillometric envelope.

5 . A method for estimating blood pressure information, the method comprising:

obtaining, at multiple measurement times in a period of time, from a pulse wave sensor included in a sensor part, a pulse wave signal representing a vital function of a user by emitting, by a light source of the pulse wave sensor, light toward to a body part of the user, and a detector of the pulse wave sensor, detecting the emitted light reflected by the body part of the user;

outputting guide information on a contact pressure to be applied by the body part of the user to a contact pressure sensor, included in the sensor part, for the period of time while the pulse wave signal is measured by the pulse wave sensor, the guide information instructing the user to gradually change the contact pressure;

obtaining, from the contact pressure sensor, contact pressure values corresponding to the contact pressure applied by the body part of the user to the sensor part during the period of time in an increasing or decreasing manner,

extracting direct current (DC) component values from the pulse wave signal using a low-pass filter;

generating a graph based on the contact pressure values and the DC component values by plotting a DC component value with respect to a contact pressure value at each of the multiple measurement times;

obtaining one or more features based on the generated graph by performing curve fitting for the graph using a fitting model and obtaining a coefficient of the curve fitting as the one or more features;

estimating the blood pressure information based on the obtained one or more features; and

outputting a blood pressure notification based on the estimated blood pressure information.

6 . The method of claim 5 , wherein the estimating the blood pressure information further comprises:

obtaining an oscillometric envelope based on an amplitude of the pulse wave signal and the contact pressure values, and

estimating the blood pressure information further based on a center of mass of a phase of contact pressure of the obtained oscillometric envelope.