Biosignal measuring device, biosignal measuring method and biosignal program

Patent metadata

Field	Value
Publication number	US-9706931-B2
Application number	US-201313774370-A
Country	US
Kind code	B2
Filing date	Feb 22, 2013
Priority date	Nov 19, 2012
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

A biosignal measuring device has a first information acquisition module, a second information acquisition module, a first calculation module, a second calculation module, a third calculation module, a heartbeat interval estimation module, a determination module, and an output module. The first information acquisition module acquires the pulse wave signal. The second information acquisition module acquires an electrocardiogram signal. The first calculation module calculates a pulse wave velocity based. The second calculation module determines a heartbeat interval. The third calculation module calculates a relationship between pulse wave velocity and the heartbeat interval. The heartbeat interval estimation module estimates an estimated heartbeat interval based on pulse wave velocity and calculated relationship. The determination module determines whether the position of the first and second information acquisition modules has changed based on the heartbeat interval and the estimated heartbeat interval. The output module outputs information.

First claim

What is claimed is:

1. A biosignal-measuring device, comprising:
a first information acquisition module configured to acquire multiple pulse wave signals from a subject at a first position;
a second information acquisition module configured to acquire multiple electrocardiogram signals from the subject at a second position different from the first position;
a first calculation module configured to calculate multiple pulse wave velocities based on signals acquired by the first information acquisition module and the second information acquisition module;
a second calculation module configured to calculate multiple heartbeat intervals based on the signals acquired by the first information acquisition module and the second information acquisition module;
a third calculation module configured to calculate a relational expression between multiple pulse wave velocities and multiple heartbeat intervals;
a heartbeat interval estimation module configured to estimate multiple estimated heartbeat intervals based on new multiple pulse wave velocities and the relational expression;
a determination module configured to determine whether a position of at least one of the first information acquisition module or the second information acquisition module is changed based on multiple heartbeat intervals and multiple estimated heartbeat intervals; and
an output module configured to output a notification based on the determination of the determination module.

2. The device according to claim 1 , wherein the output module is configured to output the notification as an audible signal.

3. The device according to claim 1 , further comprising:
a correcting module configured to correct a parameter of the relational expression to estimate a blood pressure using the multiple pulse wave velocities if the determination module determines that the position of at least one of the first information acquisition module or the second information acquisition module is changed.

4. The device according to claim 1 , wherein the third calculation module is further configured to calculate the relational expression between multiple pulse wave velocities and multiple heartbeat intervals for a period in which the first information acquisition module and the second information acquisition module are determined to be receiving signals in a stable manner.

5. The device according to claim 1 , wherein the determination module is configured to determine the position of the first information acquisition module or the second information acquisition module is changed when a difference between a calculated heartbeat interval and an estimated heartbeat interval is over a specified threshold for a specified time.

6. The device according to claim 5 , wherein the determination module is configured to update the specified threshold based on the signals acquired by the first information acquisition module or the second information acquisition module.

7. The device according to claim 1 , wherein the first information acquisition module includes a photoplethysmographic sensor.

8. The device according to claim 1 , wherein the second information acquisition module includes first and second electrodes for acquiring a biosignal.

9. The device according to claim 1 , wherein the first information acquisition module and the second information acquisition module are integrated on a single body unit.

10. The device according to claim 1 , further comprising:
an adhesive unit configured to place the first and second information acquisition modules in contact with the subject.

11. The device according to claim 10 , wherein the adhesive unit comprises a belt.

12. The device of claim 1 , further comprising:
an input module configured to receive input from the subject.

13. A biosignal measurement method, comprising:
acquiring multiple pulse wave signals of a subject at a first position on the subject;
acquiring multiple electrocardiogram signals of the subject at a second position on the subject, the second position being different from the first position;
calculating multiple pulse wave velocities using the pulse wave signals and the electrocardiogram signals;
calculating multiple heartbeat intervals using the pulse wave signals and the electrocardiogram signals;
calculating a relational expression between multiple pulse wave velocities and multiple heartbeat intervals;
estimating multiple estimated heartbeat intervals based on new multiple pulse wave velocities and the relational expression;
determining whether the first position and the second position are changed using the heartbeat intervals and the estimated heartbeat intervals; and
outputting a notification based on the determination of whether the first position and the second position are changed.

14. The method of claim 13 , wherein the multiple pulse wave signals are acquired using an optical electric pulse wave sensor.

15. The method of claim 13 , wherein calculating the multiple heartbeat intervals includes calculating a feature value of the multiple pulse wave velocities.

16. The method of claim 13 , wherein calculating the relational expression involves a linear regression between a feature width value of the pulse wave velocities and the heartbeat intervals.

17. The method of claim 13 , further comprising:
updating a parameter of the relational expression from an initial parameter value based on at least one calculated pulse wave velocity.

18. A non-transitory computer readable medium including a biosignal measuring program that when executed in a computer causes the computer to perform steps comprising:
acquiring multiple pulse wave signals of a subject at a first position on the subject;
acquiring multiple electrocardiogram signals of the subject at a second position on the subject, the second position being different from the first position;
calculating multiple pulse wave velocities using the pulse wave signals and the electrocardiogram signals;
calculating multiple heartbeat intervals using the pulse wave signals and the electrocardiogram signals;
calculating a relational expression between multiple pulse wave velocities and multiple heartbeat intervals;
estimating multiple estimated heartbeat intervals based on new multiple pulse wave velocities and the relational expression;
determining whether the first position and the second position are changed using the heartbeat intervals and the estimated heartbeat intervals; and
outputting a notification based on the determination of whether the first position and the second position are changed.

19. The non-transitory computer readable medium of claim 18 , wherein calculating the relational expression involves a linear regression between feature width values of multiple pulse wave velocities and multiple heartbeat intervals.

20. The non-transitory computer readable medium of claim 18 , wherein the steps further comprise:
outputting a blood pressure value calculated using multiple pulse wave velocities.

Assignees

• Tdk Corp

Inventors

• Fuke Sawa
• Suzuki Takuji
• Nakayama Kanako

Classifications

• A61B5/04012

  Human Necessities · mapped topic

• A61B5/0402

  Human Necessities · mapped topic

• A61B5/0295

  using plethysmography, i.e. measuring the variations in the volume of a body part as modified by the circulation of blood therethrough, e.g. impedance plethysmography · CPC title

• A61B5/02108 Primary

  from analysis of pulse wave characteristics · CPC title

• A61B5/0285

  Measuring or recording phase velocity of blood waves · CPC title