KR20170124943A - Apparatus and method for extracting cardiovascular characteristic - Google Patents

Abstract

An apparatus for extracting cardiovascular characteristics is disclosed. According to one embodiment, a cardiovascular characteristic extracting apparatus includes a first sensor unit for measuring a vibration signal generated by a pulse wave of a subject, a second sensor unit for measuring a pulse wave signal of the subject, And a body to which the first sensor unit, the second sensor unit, and the processing unit are mounted.

Description

[0001] APPARATUS AND METHOD FOR EXTRACTING CARDIOVASCULAR CHARACTERISTIC [0002]

And a device and a method for extracting cardiovascular characteristics.

Pulse wave analysis (PWA) and pulse wave velocity (PWV) methods are typically used to non-invasively extract cardiovascular features without using pressure cuffs. The PWA method is a method of extracting cardiovascular characteristics by analyzing the shape of a pulsating pulse wave or body surface pressure signal at the body end (fingertip, radial artery, etc.). The blood ejected from the left ventricle causes reflexes at the branches of the large branches such as the renal arteries and the iliac arteries, which affect the shape of the optic volume pulse or body pressure wave measured at the body end. Therefore, by analyzing this shape, it is possible to deduce arteriosclerosis, blood vessel age, and aortic pressure waveform. The PWV method is a method of extracting cardiovascular characteristics by measuring the pulse-wave propagation time. It measures the RV peak (left ventricular contraction interval) of the electrocardiogram and the optical volume of the finger or radial artery Measure the pulse transit time (PTT) between the peak of the pulse wave or the pressure pulse, and divide the approximate length of the arm to obtain the velocity at which the blood starts from the heart until it reaches the end of the body.

Generally, in order to measure ECG, the measurement position 1, heart, and measurement position 2 should form a closed circuit through the body surface with the heart in the center. Therefore, the right and left hands are simultaneously contacted with the electrodes of the measurement system, The electrodes of the system should be in contact with one side of the heart and one side of the other. This makes it difficult to use electrocardiograms in personal wearable devices.

An apparatus and method for extracting cardiovascular characteristics without the need to incorporate a separate sensor in the strap of a wrist instrument is presented.

According to one aspect, a cardiovascular characteristic extracting apparatus includes a first sensor section for measuring a vibration signal generated by a pulse wave of a subject, a second sensor section for measuring a pulse wave signal of the subject, And a body to which the first sensor unit, the second sensor unit, and the processing unit are mounted.

The cardiovascular characteristic extracting device may further include a strap formed to surround the wrist of the subject and connected to the body, and a strap for holding the wrist in a wrapped state by a tension to fix the body to the wrist.

The first sensor unit can measure the vibration transmitted to the main body through the strap when the pulse wave is generated in the radial artery while the strap is wrapped around the wrist by the tension.

The first sensor unit may include a piezoelectric sensor for measuring vibration of the pulse wave transmitted through the main body.

The first sensor unit may include a force sensor or a strain gauge that measures the contact pressure of the test object transmitted through the main body.

The first sensor unit includes a piezo bender for generating an electrical signal in response to the deformation, a rigid support for mounting both ends of the piezo bender in a state of forming a cavity with the piezo bender, And a pressure block that receives the vibration of the piezo bender and presses and deforms the piezo bender.

The first sensor unit includes a piezo bender for generating an electrical signal in accordance with the deformation, a rigid support for mounting both ends of the piezo bender in a state where a cavity is formed between the piezo bender and the rigid support body, And a force sensor that receives the vibration of the pulse wave and presses and deforms the piezo bender.

The main body includes a housing, and the housing can be mounted while the second sensor portion is exposed toward the subject.

At this time, the connecting portion between the second sensor unit and the housing may be formed to be expandable and contractible.

At this time, the housing can receive the first sensor part closer to the second sensor part than the processing part.

The second sensor unit may include a sensor board, a light source mounted on the sensor board to irradiate the subject with light, and a detector mounted on the sensor board to detect light returned from the subject.

At this time, the light source may be any one selected from a light emitting diode (LED), a laser diode, and a phosphor.

The processing unit may include a delay time calculating unit for calculating a delay time between the measured vibration signal and the pulse wave signal and a cardiovascular characteristic extracting unit for extracting cardiovascular characteristics based on the calculated delay time.

The processing unit may further include a feature point extracting unit that extracts at least one of a peak, a valley, and a slope of a vibration signal and a pulse wave signal from a feature point, and the delay time calculation unit calculates a delay Time can be calculated.

The cardiovascular characteristic extracting apparatus may further include a communication unit mounted on the main body and transmitting at least one of a vibration signal, a pulse wave signal, a feature point, a delay time, a pulse wave velocity (PWV), and a cardiovascular characteristic to an external device.

At this time, the cardiovascular characteristics may include at least one of blood pressure, blood vessel age, atherosclerosis, aortic pressure waveform, stress index and fatigue.

In addition, the cardiovascular characteristic extracting apparatus may further include a display unit for providing the extracted cardiovascular characteristics to the user under the control of the processing unit.

The processing unit may include a preprocessor for pre-processing signals measured by the first sensor unit and the second sensor unit, and a signal converter for converting the measured analog signal into a digital signal.

According to another aspect, the cardiovascular characteristic extracting apparatus includes a main body, a strap connected to the main body, the strap being formed to surround the wrist of the subject, a main body attached to the main body, A first sensor unit including a force sensor or a strain gauge for measuring a pressure signal, a second sensor unit mounted on the main body and measuring a pulse wave signal of the subject, And a processor for performing an operation related to cardiovascular characteristic extraction based on the pressure signal and the pulse wave signal.

The processing section can separate the contact pressure signal into an AC component signal and a DC component signal.

The processor may calculate the delay time of the AC component signal and the pulse wave signal, and extract the cardiovascular characteristics based on the calculated delay time.

The processor collects information on the contact state of the force sensor or the strain gauge based on the DC component signal, and determines whether the cardiovascular characteristic is extracted based on the collected information.

The processor may correct the estimated model or the extracted cardiovascular characteristic value indicating the relationship between the delay time and the cardiovascular characteristic based on the DC component signal.

According to another aspect of the present invention, there is provided a cardiovascular characteristic extracting apparatus comprising: a strap connected to a main body and a main body, the strap being formed to surround a wrist of a subject; A second sensor unit mounted on the main body and measuring a pulse wave signal of the subject and a second sensor unit mounted on the main body and performing an operation related to cardiovascular characteristic extraction on the basis of a sound wave signal and a pulse wave signal And a processing unit for processing the image data.

At this time, the microphone may include at least one of an electret microphone and a MEMS microphone.

The first sensor unit may further include a diaphragm that converts the vibration signal transmitted to the main body through the strap into a sound wave signal and transmits the sound wave signal to the microphone.

According to one aspect, a method for extracting cardiovascular characteristics from a cardiovascular characteristic device including a first sensor portion and a second sensor portion includes a body, wherein the vibration signal generated by the pulse wave of the subject through the first sensor portion is measured Measuring a pulse wave signal of the subject through the second sensor unit, and performing an operation relating to cardiovascular characteristic extraction based on the vibration signal and the pulse wave signal.

In the step of measuring the vibration signal, the wrist of the subject is wrapped by the strap connected to the body, and the vibration signal transmitted to the body through the strap when the pulse wave is generated can be measured in a state where the body is fixed to the wrist by the tension of the strap.

The step of performing the operation may include calculating a delay time between the vibration signal and the pulse wave signal, and extracting cardiovascular characteristics based on the calculated delay time.

The step of performing an operation further comprises extracting at least one of a peak, a valley, and a maximum and a minimum point of the slope from the vibration signal and the pulse wave signal as feature points, The delay time can be calculated based on the feature points.

In addition, the cardiovascular characteristic extraction method may further include providing the extracted cardiovascular characteristics to the user through a display unit.

Cardiovascular characteristics can be extracted without having to incorporate a separate sensor in the strap of the wrist device.

1 is a schematic overall structural view of a cardiovascular characteristic extracting apparatus according to an embodiment.
2 is a block diagram of an apparatus for extracting cardiovascular characteristics according to an embodiment.
3 is a detailed block diagram illustrating one embodiment of the processing portion configuration of FIG.
4A to 4C are diagrams illustrating a signal processing process of the cardiovascular characteristic extracting apparatus.
5 is a block diagram of an apparatus for extracting cardiovascular characteristics according to an embodiment.
6A is a block diagram of a main body of a cardiovascular characteristic extracting apparatus according to an embodiment of the present invention.
6B is a view for explaining the first sensor unit of the cardiovascular characteristic extracting apparatus.
7 is a block diagram of a cardiovascular characteristic extracting apparatus according to an embodiment of the present invention.
8A and 8B are block diagrams of a cardiovascular characteristic extracting apparatus according to an embodiment of the present invention.
9 is a view for explaining a cardiovascular characteristic extracting apparatus according to an embodiment.
10 is a flowchart of a cardiovascular characteristic extraction method according to an embodiment.
11 is a detailed flowchart of steps of performing a cardiovascular operation in a cardiovascular characteristic extraction method according to an embodiment.

The details of other embodiments are included in the detailed description and drawings. The advantages and features of the described techniques, and how to achieve them, will become apparent with reference to the embodiments described in detail below with reference to the drawings. Like reference numerals refer to like elements throughout the specification.

The terms first, second, etc. may be used to describe various elements, but the elements should not be limited by terms. Terms are used only for the purpose of distinguishing one component from another. The singular expressions include plural expressions unless the context clearly dictates otherwise. Also, when an element is referred to as "comprising ", it means that it can include other elements as well, without departing from the other elements unless specifically stated otherwise. Also, the terms "part," " module, "and the like described in the specification mean units for processing at least one function or operation, which may be implemented in hardware or software or a combination of hardware and software .

Hereinafter, embodiments of an apparatus and method for extracting cardiovascular characteristics will be described in detail with reference to the drawings.

1 is a schematic overall structural view of a cardiovascular characteristic extracting apparatus according to an embodiment. 2 is a block diagram of an apparatus for extracting cardiovascular characteristics according to an embodiment.

Referring to FIG. 1, the apparatus 1 for extracting cardiovascular characteristics according to the present embodiment may be a wearable device that can be worn on the wrist. As shown in the figure, the cardiovascular characteristic extracting apparatus 1 is connected to the apparatus main body 100 and the apparatus main body 100 and is formed to be flexible so as to enclose the wrist of the subject, and is kept wrapped around the wrist by a tension And straps 121 and 122 for fixing the main body to the wrist.

The display unit 110 and the operation unit 115 may be mounted on the apparatus main body 100 of the cardiovascular characteristic extracting apparatus 1. [

The display unit 110 displays various kinds of information related to cardiovascular characteristics such as blood pressure, blood vessel age, atherosclerosis, aortic pressure waveform, stress index and fatigue, various sensor signals used for extracting cardiovascular characteristics, Additional information such as analysis information of the signal, warning or alarm according to the extracted cardiovascular characteristics, and the like, and provide the information to the user. At this time, the display unit 110 can provide information to the user in various predefined visual / non-visual methods. For example, if the extracted blood pressure corresponds to a risk value, it can be displayed in red, and conversely, if the blood pressure is normal, it can be displayed in green.

Meanwhile, the display unit 110 may be equipped with a touch input function, and a user may input a variety of commands using a touch input function and output a user interface so that a necessary operation can be performed.

The operation unit 115 may include a power button for receiving a user's control command and transmitting the command to the processing unit 220 and for inputting a command for turning on / off the power of the cardiovascular characteristic extracting apparatus 1. [

2, the sensor unit 210 and the processing unit 220 may be additionally mounted on the apparatus main body 200 according to an aspect of the present invention.

The sensor unit 210 measures a sensor signal necessary for extracting cardiovascular characteristics. As shown in the figure, the sensor unit 210 may include a first sensor unit 211 and a second sensor unit 212.

The first sensor unit 211 measures a first signal generated by a pulse wave of the subject. For example, when the straps 121 and 122 generate a pulse wave in the radial artery while the wrist is wrapped around by the tension, mechanical vibrations are transmitted to the main body 100 through the straps 121 and 122. At this time, the first sensor unit 211 can measure the vibration signal transmitted to the main body 100 through the straps 121 and 122 as a first signal.

The first sensor unit 211 includes a sensor element for measuring the vibration of the radial pulse wave transmitted to the main body 100 through the straps 121 and 122. The sensor element may be a piezoelectric element for converting mechanical vibration into an electrical signal, And a piezoelectric sensor. For example, a piezo-electric piezoelectric sensor may be realized as a piezoelectric bender in which a potential is generated according to mechanical deformation, or a series / parallel connection thereof. At this time, the piezoelectric sensor may be based on a piezoelectric polymer such as lead zirconate titanate (PZT) or a piezoelectric polymer such as PVDF (polyvinylidene fluoride). However, the present invention is not limited thereto and may include various sensors capable of measuring mechanical vibration of a pulse wave.

The second sensor unit 212 measures a second signal generated by the pulse wave of the subject. For example, the second sensor unit 212 can irradiate the subject with light, detect the light coming back from the subject, and measure the pulse wave signal as the second signal. The second sensor unit 212 may be formed on the main body 100 so as to be in close contact with the area of the back of the wrist. The second sensor unit 212 may measure a pulse wave signal generated from capillary blood or venous blood of the wrist. For example, the second sensor unit 212 may include a light source that emits light to a subject as a sensor element for measuring a pulse wave signal, and a detector that detects light returned from the subject to measure a pulse wave signal have. At this time, the light source may include, but is not limited to, a light emitting diode (LED), a laser diode, and a phosphor.

Meanwhile, the first sensor unit 211 and the second sensor unit 212 may be formed as an array of a plurality of sensor elements, if necessary for matching with the blood vessels of the wrist area and improving the signal quality.

The processing unit 220 may receive the measured first and second signals and may perform various operations associated with the extraction of cardiovascular characteristics using the received first and second signals.

3 is a detailed block diagram illustrating one embodiment of the processing portion configuration of FIG. 4A to 4C are diagrams illustrating a signal processing process of the cardiovascular characteristic extracting apparatus.

3, an embodiment of the processing unit 220 will be described in more detail. The processing unit 220 may include a preprocessing unit 221, a signal converting unit 222, a feature point extracting unit 223, a delay time calculating unit 224, and a cardiovascular feature extracting unit 225.

When the first signal and the second signal are received from the first sensor unit 211 and the second sensor unit 212, the preprocessing unit 221 performs a preprocess such as noise reduction and signal amplification of the received signal. For example, you can perform preprocessing tasks such as normalizing the signal and removing trends and offsets, removing high frequency noise using detrending, signal smoothing, and a low pass filter.

The signal converting unit 222 may convert the measured first signal and the second signal into a digital signal when the measured signal is an analog signal.

4A shows a waveform of signals obtained by analog-to-digital conversion of the first signal 411 and the second signal 412 measured by the second sensor unit 212 of the first sensor unit 211 to 1000 Hz, Respectively.

The feature point extracting unit 223 extracts feature points for obtaining the delay time between the first signal 411 and the second signal 412 shown in FIG. 4A. For example, the feature point extracting unit 223 extracts the prominent points in the first signal 411 and the second signal 412 as feature points, combines the extracted feature points or feature points, and outputs the signals 411 and 412 as shown in FIG. (M1, M2). The feature point includes, but is not limited to, a peak point, a valley point, a maximum point and a minimum point of a slope of the first signal 411 and the second signal 412, and the like. FIG. 4B illustrates the extraction and marking of the maximum points of the slopes of the positive and negative second signals 411 and 412 as feature points.

The delay time calculation unit 224 can calculate the delay between the marked points M1 and M2 of the first signal 411 and the second signal 412. [ At this time, the delay time means the time taken for the pulsation of the radial artery to be reflected on the wrist in the direction of the back of the hand to the pulse wave. The first signal measured by the first sensor unit 211 is a mechanical vibration signal generated by the pulse wave of the radial artery, and the second signal measured by the second sensor unit 212, such as a pulse wave signal, Since the delivered arterial blood is reflected after being reflected after passing through the main blood vessels of the wrist and hand, the pulse wave signal measured between the mechanical vibration signal measured by the first sensor unit 211 and the pulse wave signal measured by the second sensor unit 212 The delay time is similar to the local pulse wave velocity PWV (pulse wave velocity) at the end of the body.

The cardiovascular characteristic extracting unit 225 may acquire a series of patterns based on the delay time between the first signal and the second signals continuously calculated by the delay time calculating unit 224. [ In addition, the cardiovascular characteristics can be extracted based on the thus obtained delay time. The cardiovascular characteristics may include, but are not limited to, blood pressure, blood vessel age, atherosclerosis, aortic pressure waveform, stress index and fatigue.

4C is a graph showing a series of patterns obtained through a delay time between consecutively obtained first and second signals, and the upper part of FIG. 4C is a graph showing systolic blood pressure, systolic blood pressure when the blood pressure change was induced in minutes by means of an isometric holding or isometric exercise. Referring to FIG. 4C, it can be seen that there is a certain correlation between the systolic blood pressure and the series of patterns obtained by the delay time between the first signal and the second signal.

Meanwhile, the cardiovascular characteristic extracting unit 225 may generate a correlation model indicating a correlation between the delay time between the first signal and the second signal and the systolic blood pressure. At this time, the correlation model may be generated in the form of a mathematical algorithm capable of estimating the blood pressure, for example, from the average delay time between the first signal and the second signal, but is not limited thereto and may be stored in the storage device in the form of a matching table. At this time, the storage device may be a flash memory type, a hard disk type, a multimedia card micro type, a card type memory (e.g., SD or XD memory) A random access memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM) But is not limited to, a storage medium such as a disk, an optical disk, and the like.

For example, the cardiovascular characteristic extracting unit 225 measures a first signal and a second signal for a predetermined period of time, collects it as learning data, and calculates a delay time between the first signal and the second signal using the collected learning data . In addition, the systolic blood pressure for a predetermined period of time can be measured through breath holding or isometric excellence, and a blood pressure estimation equation showing a correlation using the systolic blood pressure and the delay time calculated using the learning data can be generated as a correlation model have.

5 is a block diagram of an apparatus for extracting cardiovascular characteristics according to an embodiment.

5, the main body 500 of the cardiovascular characteristic extracting apparatus 1 may further include a communication unit 510 in addition to the sensor unit 210 and the processing unit 220. FIG.

The sensor unit 210 includes a first sensor unit 211 for measuring a vibration signal generated by the pulse wave generated in the radial artery as a first signal, And a second sensor unit 212 for measuring a pulse wave signal of the upper part of the wrist or a pulse wave of the venous blood, which is reflected after passing through the main blood vessels of the wrist.

The processing unit 220 processes various operations using the first sensor and the second sensor measured by the first sensor unit 211 and the second sensor unit 212. At this time, the processing unit 220 may control the communication unit 510 to connect with the external device 550, and may perform various operations through cooperation with the external device 550 connected thereto. At this time, the processing unit 220 may acquire necessary information such as the measured first signal and second signal, the preprocessed signal, the calculated delay time , PWV, correlation model, extracted feature points, extracted cardiovascular characteristics information, and the like.

The communication unit 510 can access the communication network by using the communication technology under the control of the processing unit 220 and can transmit and receive necessary data by connecting with the external device 550 connected to the same communication network. At this time, the communication technology may be a Bluetooth communication, a BLE (Bluetooth Low Energy) communication, a near field communication unit, a WLAN communication, a Zigbee communication, an IrDA , Wi-Fi Direct (WFD) communication, ultra wideband (UWB) communication, Ant + communication, WIFI communication, 3G, 4G and 5G communication technologies.

For example, when the cardiovascular characteristic is extracted based on the first signal and the second signal, the processing unit 220 transmits the extracted cardiovascular characteristic to the external device 550 through the communication unit 510, For example, a speaker, a display, a haptic device, or the like. At this time, the external device 550 may be a mobile terminal such as a smart phone, a tablet PC, and the like, which can be carried by a user having a relatively higher computing performance than the cardiovascular characteristic extracting device 1. However, And the like.

In another example, when the external device 550 has a relatively high computing capability and has a function of extracting cardiovascular characteristics using sensor signals, the communication unit 510 controls the communication unit 510, The first signal and the second signal measured by the first sensor unit 211 and the second sensor unit 212 may be transmitted to the external device 550 so as to perform the cardiovascular characteristic extraction operation. At this time, the external device 550 may be a device such as a smart phone, a tablet PC, a desktop PC, a notebook PC, and a server equipped with a cardiovascular characteristic extraction function. The external device 550 can extract the cardiovascular characteristics when a sensor signal is received from the communication unit 510 and provide the extracted cardiovascular characteristic to the user through the interface module mounted on the external device 550. When the cardiovascular characteristic information is received from the external device 550 through the communication unit 510, the processing unit 220 can provide the cardiovascular characteristic information to the user through the display unit.

As another example, if the processing unit 220 calculates the delay time between the first signal and the second signal and provides the delay time information to the external apparatus 550, the external apparatus 550 uses the correlation model managed by the external apparatus 550, The cardiovascular characteristics such as the blood pressure of the user can be extracted using the received delay time.

However, the collaboration operation between the cardiovascular characteristic device 1 and the external device 550 of the present embodiment is not limited to these examples.

6A is a block diagram of a main body of a cardiovascular characteristic extracting apparatus according to an embodiment of the present invention. 6B is a view for explaining the first sensor unit of the cardiovascular characteristic extracting apparatus.

6A, the structure of the main body 600 of the cardiovascular characteristic extraction apparatus 1 according to the present embodiment includes a first sensor unit 610, a second sensor unit 620, a main board 630, a display 640 And a housing 650.

The first sensor unit 610 is mounted in the housing 650. At this time, the housing 650 receives the first sensor unit 610 relatively closer to the second sensor unit 620 than the main board 630 on which the processing unit is mounted.

The first sensor unit 610 may include a piezo bender 611 that is mechanically deformed by pressure and generates an electrical signal according to the deformation. The piezo bender 611 may be formed as an array of two or more stacked layers as shown. The piezoelectric bender 611 may be electrically connected to the sensor board 623 of the second sensor unit 620 and the electrical signal generated by the piezo bender 611 may be transmitted as a first signal to the sensor board 623 do. However, the present invention is not limited thereto, and the piezoelectric bender 611 may be electrically connected to the main board 640, and the generated electrical signal may be directly transmitted to the main board.

The first sensor unit 610 may further include a pressure block 612 that generates a mechanical deformation of the piezo bender 611. At this time, the pressing block 612 may be formed such that one side is in close contact with the sensor board 623 and the other side is in close contact with the piezo bender 611. 6B, the pressure block 610 transmits the mechanical vibration generated by the (1) radial pulse wave to the main body 600 through the tension of the strap 680 and the movement of the sensor board 623 (3) The piezo bender 611 can be pressed against the sensor board 623 to generate deformation. At this time, the pressing block 612 may be formed of a rigid material.

The first sensor unit 610 includes a rigid support 613 formed of a rigid material so as to support both ends of the piezoelectric bender 611 in a state where a cavity 615 is formed between the first sensor unit 610 and the piezo bender 611 .

The second sensor unit 620 is mounted on the housing 650 so as to be exposed in the direction of the user's hand. The second sensor unit 620 includes a light source 621 mounted on the sensor board 623 to closely contact the subject and irradiate the light and a detector 622 mounted on the sensor board to detect light returned from the subject .

The second sensor unit 620 may further include a sensor board 623 having both ends connected to the housing 650. At this time, the connection portion 625 of the sensor board 623 and the housing 650 may be formed to be expandable and contractible. When the mechanical vibration generated by the radial artery is transmitted to the housing 650 of the main body 600 through the strap 680, the extendable connection portion 625 of the housing 650 is mechanically vibrated, So that the pressing block 612 of the first sensor unit 610 deforms the piezo bender 611 as described above.

The sensor board 623 is electrically connected to the light source 621 and the detector 622 to transmit the control signal of the processing unit to the light source 621 and receive the measured second signal from the detector 622. [

The main board 630 is supported by a cover 651, and a display unit 640 for providing various information to the user may be mounted on one side. In addition, the main board 630 is electrically connected to the sensor board 623 through the element 631. The processing unit 220 may be mounted on the main board 630 and the processing unit 220 may receive the first signal and the second signal received through the element 631 electrically connected to the sensor board 623 Various operations necessary for cardiovascular characteristic extraction can be performed.

7 is a block diagram of a cardiovascular characteristic extracting apparatus according to an embodiment of the present invention. The structure of the main body of the cardiovascular characteristic extracting apparatus according to the present embodiment is one modified example of the first sensor unit in the embodiment of FIG. 6A.

 7, includes a first sensor unit 710, a second sensor unit 620, a main board 630, a display 640, and a housing 650. Hereinafter, a configuration that does not overlap with the embodiment of FIG. 6A will be mainly described.

The first sensor unit 710 is mounted in the housing 650 and the housing 650 is configured such that the first sensor unit 710 is relatively closer to the second sensor unit 620 than the main board 630, Accept. The first sensor portion 710 includes a piezo bender 611 that is mechanically deformed by pressure and generates an electrical signal as it deforms, wherein the piezo bender 611 includes two or more layers Shaped array. The piezoelectric bender 611 may be electrically connected to the sensor board 623 of the second sensor unit 620 and the electrical signal generated by the piezo bender 611 may be transmitted to the sensor board 623. However, the present invention is not limited thereto, and the piezoelectric bender 611 may be electrically connected to the main board 640, and the generated electrical signal may be directly transmitted to the main board.

Also, the first sensor unit 710 may include a force sensor, unlike the embodiment of FIG. 6A. However, the present invention is not limited thereto and may include various sensors for measuring contact pressure such as strain gauge. A force sensor 711 is formed in close contact with the lower end of the sensor board 623 to measure a contact pressure signal of the test object transmitted through the main body 700. In addition, the force sensor 711 receives the vibration of the pulse wave generated in the radial artery through the strap, and presses the piezo bender 611 to deform it. At this time, according to one example, a pressing member 712 for easily pressing the piezo bender 611 may be formed at the lower end of the force sensor 711.

At this time, the contact pressure signal measured by the force sensor 711 is transmitted to the sensor board 623 as a first signal together with the vibration signal measured by the piezo bender 611, and the sensor board 623 and the main board 630 to the main board 630 via the connecting device.

The first sensor unit 710 includes a rigid support 613 formed of a rigid material so as to support both ends of the piezoelectric bender 611 in a state where a cavity 615 is formed between the first sensor unit 710 and the piezo bender 611 .

The processing unit 220 mounted on the main board 630 performs various operations required for cardiovascular characteristic extraction based on the first signal and the second signal received through the element 631 electrically connected to the sensor board 623 . For example, the processing unit 220 may calculate the delay time based on the vibration signal of the first signal and the pulse wave signal of the second signal, and extract cardiovascular characteristics using the calculated delay time. In addition, the processor 220 may monitor blood perfusion, capillary compliance, and the like using the DC component of the first signal, which reflects the pressure of the sensor against the skin, as a contact pressure signal.

The second sensor unit 620 includes a light source 621 and a detector 622 which are mounted on the housing 650 and are mounted on the sensor board 623 so as to be exposed in the direction of the user's hand. The second sensor unit 620 further includes a sensor board 623 having both ends connected to the housing 650 and the connection site 625 between the sensor board 623 and the housing 650 is connected to the pulse wave of the radial artery To effectively transmit the mechanical vibration generated by the force sensor 711 to the force sensor 711.

8A and 8B are block diagrams of a cardiovascular characteristic extracting apparatus according to an embodiment of the present invention. The main body structure of the cardiovascular characteristic extracting apparatus according to the present embodiments is a modification of the first sensor unit in the embodiment of FIG.

Referring to FIGS. 8A and 8B, the first sensor unit 810 may be implemented by omitting the piezo bender 611 in the first sensor unit 710 of FIG. 7A. 8A, the first sensor unit 810 includes a force sensor 811 of an appropriate sensitivity and a pressure sensor 812 of a force sensor 811 in a state where the cavity 615 is formed. And a rigid support 813 for supporting pressing. Here, the force sensor is an example of a sensor for measuring contact pressure, but not limited thereto, and may include various sensors capable of measuring a contact pressure such as a strain gauge.

The mechanical vibration generated by the pulse wave of the radial artery is transmitted to the sensor board 623 of the main body 800, particularly, the sensor board 623 of the second sensor unit 620 via the strap 680, The force sensor 811 formed at the lower end of the rigid support 813 can transmit a contact pressure signal generated as the pressing member 812 presses the rigid support 813 to the sensor board 623 as a first signal.

The processing unit 220 mounted in the main board 630 can separate the received first signal into the AC component signal and the DC component signal upon receiving the contact pressure signal as the first signal. The processor 220 calculates the delay time between the two signals using the separated AC component signal and the pulse wave signal that is the second signal measured by the second sensor unit 620, The characteristics can be extracted.

Further, the processing unit 220 collects information on the contact state of the force sensor including the contact pressure at which the force sensor 811 presses the object using the separated DC component signal, and based on the collected information, Signals can be used to determine whether to extract cardiovascular characteristics or re-measure signals, and to determine whether an estimated model required for cardiovascular or cardiovascular characteristics is calibrated.

For example, the body 800 may not be positioned at the correct examination point due to the thickness of the wrist to which the body 800 is worn, the change of the wearing position due to the wearing state, the movement, or the like. In this case, the processing unit 220 compares the contact pressure at which the force sensor 811 presses the inspected object with a preset threshold value, and if the contact pressure is equal to or higher than the threshold value, the processing unit 220 outputs the contact pressure to the first sensor unit 810 and the second sensor unit 620 And the first sensor unit 810 and the second sensor unit 820 may be controlled to re-measure the cardiovascular characteristic extraction operation by determining that the measured signals are not correct .

In addition, since the contact pressure by the force sensor 811 affects blood perfusion or capillary compliance, the processing unit 220 calculates the contact pressure based on the DC component, The amount of change in blood perfusion or capillary blood flow due to the contact pressure can be corrected by reflecting the estimated model or the estimated cardiovascular characteristic value indicating the relationship between the delay time and the cardiovascular characteristic. At this time, the estimated model may be a mathematical form between the delay time and the cardiovascular characteristics, or a mapping table in which the delay time and the cardiovascular characteristic values are mapped, but the present invention is not limited thereto.

8B, an embodiment of the main body structure of the cardiovascular characteristic extraction apparatus may omit the rigid support 813 in the first sensor unit 810 according to the embodiment of FIG. 8A. The force sensor 811 of the first sensor unit 810 is connected to the housing 650 through the housing 650 and the force sensor 811 of the first sensor unit 810 is connected to the housing 650, It is possible to measure the contact pressure signal. According to the present embodiment, the volume of the main body structure can be reduced.

9 is a view for explaining a cardiovascular characteristic extracting apparatus according to an embodiment.

The apparatus for extracting cardiovascular characteristics according to the present embodiment is a modification of the first sensor unit in the embodiment of FIG. 6A. It is assumed that the basic structure of the main body 900 excluding the first sensor unit is the same as the embodiment of FIG. 6A.

Referring to FIG. 9, the first sensor unit in the main body 900 may include a microphone 910. The microphone 910 can measure (3) the sound wave signal generated by (1) the mechanical vibration transmitted to the main body 900 through the strap 680 when (2) the pulse wave occurs in the radial artery. The sound wave signal measured by the microphone can be transmitted to the processing unit as the first signal. For example, the microphone includes, but is not limited to, an electret microphone, a micro electro mechanical system (MEMS) microphone, and the like.

The first sensor unit may further include a diaphragm at the front end of the microphone 910 to convert a mechanical vibration signal transmitted through the tension of the strap into a sound wave signal and transmit the converted sound wave signal to the microphone 910.

At this time, the processing unit 220 calculates the delay time using the sound wave signal measured and transmitted by the microphone 910 and the pulse wave signal measured by the second sensor unit, and extracts cardiovascular characteristics using the delay time have.

6A to 9, various modified embodiments of the main body structure of the cardiovascular characteristic extracting apparatus 1 have been described. However, the present invention is not limited to the illustrated embodiments, and various modifications may be made.

10 is a flowchart of a cardiovascular characteristic extraction method according to an embodiment. 11 is a detailed flowchart of steps of performing a cardiovascular operation in a cardiovascular characteristic extraction method according to an embodiment.

Referring to FIG. 10, an embodiment of a cardiovascular characteristic extracting method performed by the cardiovascular characteristic extracting apparatus 1 will be described. First, a cardiovascular characteristic extracting apparatus 1 extracts a cardiovascular characteristic, which is generated by a pulse wave of a subject through a first sensor unit A first signal is measured (1010). For example, when the strap of the cardiovascular characteristic extracting apparatus 1 is wrapped around the wrist by the tension, when the pulse wave is generated in the radial artery, if the mechanical vibration is transmitted to the body through the strap, the vibration signal is measured as the first signal . For example, the first sensor portion may include a piezoelectric sensor, such as a piezoelectric bender, that is deformed in response to mechanical vibration to generate an electrical signal.

Next, the second signal generated by the pulse wave of the subject is measured through the second sensor unit (1020). For example, the second sensor unit may be formed on the main body so as to be in close contact with the area of the back of the wrist, and may irradiate light to the upper part of the wrist and detect the returning light to measure pulse wave signals generated from capillary blood or venous blood of the wrist .

The first signal and the second signal may then be used to perform various operations associated with the extraction of cardiovascular characteristics (1030).

Referring to FIG. 11, step 1030 will be described in detail. A first signal and a second signal are received from the first sensor unit and the second sensor unit (1031). At this time, a preprocessing operation such as detrending the first signal and the second signal as necessary, eliminating high frequency noise using signal smoothing and a low pass filter, Can be performed.

The feature points may then be extracted 1032 from each received signal or preprocessed signal. At this time, the minutiae indicate the prominent points of the two signals for calculating the delay time between the two signals. For example, the peak point, the valley point, the maximum point and the minimum point of the gradient of the first signal and the second signal But is not limited thereto.

Then, when the feature points are extracted from the respective signals, the delay time between the first signal and the second signal can be calculated based on the feature points (1033). At this time, the delay time is the time required for the pulse wave of the radial artery to be reflected in the pulse wave of the wrist in the direction of the back of the hand, which is a factor reflecting the local pulse wave propagation velocity PWV of the body terminal.

Then, the user's cardiovascular characteristics can be extracted using the calculated delay time (1034). At this time, it is also possible to extract the cardiovascular characteristics corresponding to the calculated delay time using the correlation model generated in advance. In this case, the correlation model can be generated in advance in the form of a mathematical expression or a matching table indicating a correlation between cardiovascular characteristics such as delay time and blood pressure.

The extracted cardiovascular characteristics may then be provided to the user via a display (1035). At this time, the extracted cardiovascular characteristics can be provided to the user in various predefined visual / non-visual ways. For example, blood pressure information may be provided in a color corresponding to a corresponding range of blood pressure extracted on a user-by-user or commonly-applicable basis. In addition, appropriate guidance or warning information may be displayed based on the extracted cardiovascular characteristics.

In the meantime, the embodiments can be embodied in a computer-readable code on a computer-readable recording medium. A computer-readable recording medium includes all kinds of recording apparatuses in which data that can be read by a computer system is stored.

Examples of the computer-readable recording medium include a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device and the like, and also a carrier wave (for example, transmission via the Internet) . In addition, the computer-readable recording medium may be distributed over network-connected computer systems so that computer readable codes can be stored and executed in a distributed manner. In addition, functional programs, codes, and code segments for implementing the embodiments can be easily deduced by programmers of the related art.

It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

1: cardiovascular characteristic extraction device
100, 200, 500, 600, 700,
110, 640: display portion 115:
121, 122, 600: Strap 210:
211, 610, 710, 810: first sensor unit 212, 620:
220: processing section 221: preprocessing section
222: signal converting unit 223: feature point extracting unit
224: Delay time calculation unit 225: Cardiovascular characteristic extraction unit
510: communication unit 611: piezo bender
612: Press block 613: Rigid support
621: Light source 622: Detector
623: Sensor board 630: Main board
650: housing 600: strap
711, 811: force sensor 712, 812:
813: rigid support 910: microphone

Claims (31)

A first sensor unit for measuring a vibration signal generated by the pulse wave of the subject;
A second sensor unit for measuring a pulse wave signal of the subject;
A processor for performing an operation relating to cardiovascular characteristics based on the measured vibration signal and the pulse wave signal; And
And a main body to which the first sensor unit, the second sensor unit, and the processing unit are mounted. The method according to claim 1,
And a strap which is formed so as to surround the wrist of the subject and is connected to the body and holds the wrist in a wrapped state by a tension so as to fix the body to the wrist. 3. The method of claim 2,
Wherein the first sensor unit comprises:
Wherein the strap measures the vibration transmitted to the main body through the strap when the pulse wave is generated in the radial artery while the wrist is wrapped by the tension. The method according to claim 1,
Wherein the first sensor unit comprises:
And a piezoelectric sensor for measuring a vibration of a pulse wave transmitted through the main body. 5. The method of claim 4,
Wherein the first sensor unit comprises:
And a force sensor or strain gauge for measuring a contact pressure of the test object transmitted through the main body. The method according to claim 1,
Wherein the first sensor unit comprises:
A piezo bender generating an electrical signal according to the deformation;
A rigid support mounted in the body to support both ends of the piezoelectric bender in a state where a cavity is formed between the piezoelectric bender and the piezoelectric bender; And
And a pressure block that receives the vibration of the pulse wave and presses and deforms the piezoelectric bender. The method according to claim 1,
Wherein the first sensor unit comprises:
A piezo bender generating an electrical signal according to the deformation;
A rigid support mounted in the body to support both ends of the piezoelectric bender in a state where a cavity is formed between the piezoelectric bender and the piezoelectric bender; And
And a force sensor for measuring a contact pressure of the subject transmitted through the main body and pressing the piezo bender by receiving the vibration of the pulse wave. The method according to claim 1,
The body including a housing;
And the housing is mounted while the second sensor unit is exposed toward the subject. 9. The method of claim 8,
And a connecting portion between the second sensor unit and the housing is formed to be expandable and contractible. 9. The method of claim 8,
Wherein the housing receives the first sensor part closer to the second sensor part than the processing part. The method according to claim 1,
Wherein the second sensor unit comprises:
Sensor board;
A light source mounted on the sensor board to irradiate light to the subject; And
And a detector mounted on the sensor board to detect light coming back from the subject. 12. The method of claim 11,
Wherein the light source is one selected from the group consisting of a light emitting diode (LED), a laser diode, and a fluorescent material. The method according to claim 1,
The processing unit
A delay time calculation unit for calculating a delay time between the measured vibration signal and the pulse wave signal; And
And a cardiovascular characteristic extracting unit for extracting a cardiovascular characteristic based on the calculated delay time. 14. The method of claim 13,
The processing unit
And a feature point extracting unit that extracts at least one of a peak, a valley, and a maximum and a minimum point of the peak, valley, and slope of the vibration signal and the pulse wave signal,
The delay time calculation unit
And calculating the delay time using the extracted minutiae. 15. The method of claim 14,
And a communication unit installed in the main body for transmitting at least one of the vibration signal, pulse wave signal, feature point, delay time, pulse wave velocity (PWV), and cardiovascular characteristics to an external device. 14. The method of claim 13,
Wherein the cardiovascular characteristic comprises at least one of blood pressure, blood vessel age, atherosclerosis, aortic pressure waveform, stress index and fatigue. 14. The method of claim 13,
And a display unit for providing the extracted cardiovascular characteristics to the user under the control of the processing unit. 14. The method of claim 13,
Wherein,
A preprocessor for preprocessing signals measured by the first sensor unit and the second sensor unit; And
And a signal converting unit for converting the measured analog signal into a digital signal. main body;
A strap connected to the body and configured to wrap the wrist of the subject;
A first sensor unit mounted on the main body and including a force sensor or a strain gauge for measuring a contact pressure signal of a subject due to a vibration transmitted to the main body through the strap when a pulse wave is generated;
A second sensor unit mounted on the main body and measuring a pulse wave signal of the subject; And
And a processor mounted on the main body for performing an operation relating to cardiovascular characteristic extraction based on the contact pressure signal and the pulse wave signal. 20. The method of claim 19,
The processing unit
And separates the contact pressure signal into an AC component signal and a DC component signal. 21. The method of claim 20,
The processing unit
Calculating a delay time of the AC component signal and the pulse wave signal, and extracting the cardiovascular characteristics based on the calculated delay time. 22. The method of claim 21,
The processing unit
Collecting information on the contact state of the force sensor based on the DC component signal, and determining whether to extract the cardiovascular characteristics based on the collected information. 22. The method of claim 21,
The processing unit
And correcting the extracted cardiovascular characteristic value based on the DC component signal. main body;
A strap connected to the body and configured to wrap the wrist of the subject;
A first sensor unit mounted on the main body and including a microphone for measuring a sound wave signal generated by a vibration transmitted to the main body through the strap when a pulse wave is generated;
A second sensor unit mounted on the main body and measuring a pulse wave signal of the subject; And
And a processor mounted on the main body for performing an operation relating to cardiovascular characteristic extraction based on the sound wave signal and the pulse wave signal. 25. The method of claim 24,
The microphone
An electret microphone, and a MEMS microphone. 25. The method of claim 24,
The first sensor unit
And a diaphragm for converting the vibration signal transmitted to the main body through the strap into a sound wave signal and delivering the sound wave signal to the microphone. A method for extracting cardiovascular characteristics from a cardiovascular apparatus including a first sensor unit and a second sensor unit,
Measuring a vibration signal generated by the pulse wave of the subject through the first sensor unit;
Measuring a pulse wave signal of the subject through the second sensor unit; And
And performing an operation related to cardiovascular characteristic extraction based on the vibration signal and the pulse wave signal. 28. The method of claim 27,
Wherein measuring the vibration signal comprises:
Wherein the vibration signal transmitted to the main body through the strap when the pulse wave is generated is measured while the wrist of the subject is wrapped around the wrist by the strap connected to the main body and the main body is fixed to the wrist by the tension of the strap. 28. The method of claim 27,
Wherein performing the operation comprises:
Calculating a delay time between the vibration signal and the pulse wave signal;
And extracting cardiovascular characteristics based on the calculated delay time. 30. The method of claim 29,
The step of performing the operation
Extracting at least one of a peak, a valley, and a maximum and minimum points of the gradient from the vibration signal and the pulse wave signal as a feature point,
The step of calculating the delay time
And calculating the delay time based on the extracted minutiae. 30. The method of claim 29,
And providing the extracted cardiovascular characteristics to a user through a display unit.

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