KR20120057813A - Heart rate measurement method using optical pulse wave - Google Patents

Abstract

PURPOSE: A method for measuring a heartbeat is provided to minimize distortion of heartbeat measurement data by reducing dynamic noise generated during exercise and to minimize the inconvenience of a patient. CONSTITUTION: An exercise type is selected in a mobile apparatus which is connected with a heartbeat measuring system(100). Information in regard to the selected exercise type is transmitted to a controller. The controller uses a light source which is optimum to the selected exercise type among light sources of a signal input unit(200). The signal input unit receives photo-plethysmograph and transmits the photo-plethysmograph to a comparison unit. The comparison unit eliminates dynamic noise signal from the photo-plethysmograph and changes the photo-plethysmograph into an identifiable photo-plethysmograph signal. The comparison unit receives the identifiable photo-plethysmograph signal and stores it in a storing and transmitting unit(115).

Description

Heart rate measurement method using optical pulse wave {omitted}

Recently, apnea during sleep due to atherosclerosis, hypertension, and sudden death due to stroke due to high protein and high fat food intake accumulate more frequently than in the past. Accordingly, the necessity of a device for continuously monitoring the health condition in daily life is increasing, and according to the development of the electronic medical device industry, devices for monitoring the health in daily life are continuously appearing one after another.

Biosignal measurement techniques for diagnosing abnormalities in the circulatory system can be classified into invasive and non-invasive methods. Invasive methods are to penetrate the skin, or insert measurement sensors and probes such as the esophagus, airways, urethra, and blood vessels to measure signals to be measured. These methods are inconvenient to the subject by inserting several probes into the human body of the subject. On the other hand, non-invasive method is a method that can minimize the discomfort and pain of the patient to measure by using a sensor instead of the probe to the human body such as electrodes, sensors, ultrasound. Through the development of non-invasive methods, the development of measurement technology, signal processing technology, wired / wireless communication, and multimedia technology, as well as the development of health-related bio signals only in a limited area, such as a hospital, are available in areas where there are no medical personnel such as doctors and nurses. Several methods are being introduced to enable continuous medical instrumentation through measurement, transmission and storage in space.

The waveform of the general light volume pulse wave generated by the heartbeat is divided into the DC component caused by skin, bone, tissue, venous blood and non-pulsated arterial blood, and the AC component changed by the pulsation of arterial blood, where the blood flow of blood vessels in the tissue Since the volume change is the same as the heart rate change, the heartbeat can be detected by extracting the AC signal caused by the pulsation of arterial blood. Non-invasive methods for detecting heart rhythm by extracting AC signals caused by pulsation of arterial blood include optical detection methods, electrical detection methods, and mechanical detection methods.

The electrical detection method is to measure the heart rate by attaching an electrode on the skin to measure the change in tissue electrical impedance or admittance. The heart rate measurement using the electrical detection method is performed for ischemic heart disease such as arrhythmias, angina pectoris, myocardial infarction, and atrium. Diagnosis of hypertrophy and enlargement of the ventricles is possible, but due to the nature of the device, it is inconvenient to constantly measure the heartbeat of an individual.

The mechanical pulsation method detects heart pulsation through pressure transducers such as piezoelectric elements, rossel salt application sensors, and semiconductor pressure sensors. Since the mounting position is limited to a specific part of the body (wrist, chest, etc.), there are disadvantages in that it is difficult to use variously. In addition, there is a disadvantage in that a constant sensor position must be corrected during an active exercise.

On the other hand, the optical detection method is a method that detects light having good correlation with hemoglobin in blood by irradiating arterial blood close to the skin, which is simple and convenient in structure but difficult to distinguish from dynamic noise generated during exercise or movement. There is this.

One of the non-invasiv methods for measuring heart rate is the method of measuring heart rate using optical volume pulse waves to limit the errors that can occur by estimating blood pressure as a single component of the extension of the vessel wall. It is possible to measure blood pressure more precisely by defining the blood pressure according to the signal, and studies on blood pressure estimation using only volume pulse using the reflected wave arrival time (ΔTDVP) without acquiring an ECG signal It's going on.

The present invention relates to a heart rate measurement device that is simple in structure and simple and convenient heart rate measurement using light volume pulse wave.

In addition, the present invention relates to a heart rate measuring apparatus utilizing light volume pulse wave that can be worn at all times during daily life or exercise.

The present invention also relates to a method and apparatus for minimizing heart rate measurement data distortion due to dynamic noise (dynamic noise) generated during movement, which is a disadvantage of the optical detection method.

The present invention also relates to a sensor utilizing a light volume pulse wave that can be worn at all times during daily life or exercise.

The present invention is a bio-signal measurement, transmission and storage for enabling the measurement of health-related bio-signal available only in a limited area such as a hospital, doctors, nurses, etc. A method and apparatus for storage.

The present invention is a control unit for selectively activating the signal input unit (sensor) and the comparison unit for removing the noise and the dynamic noise DB and the light source of the signal input unit and transmits the measured heart rate data to the interlocked mobile device The present invention relates to a heart rate measuring apparatus using a portable light volume pulse wave configured.

The present invention can be worn on a variety of body parts by a combination of a small sized light source (Laser Diode) and a light-receiving portion (Photo Diode), and also utilizes a portable light volume pulse wave that minimizes the noise to be used during exercise as well as daily life. It relates to a heart rate measuring device.

In addition, the present invention by setting and storing the dynamic noise generated by each exercise type to minimize the dynamic noise so that it can be used during exercise by separating the optical volume pulse wave and the dynamic noise measured during exercise to extract the optical volume pulse wave dynamic noise DB The present invention relates to a heart rate measurement device using a portable light volume pulse wave.

In addition, the present invention is to set the optical volumetric pulse wave measurement cycle (number of optical volumetric pulse waves to be measured before transmitting to the mobile device interlocked) and transmission period for each exercise type, and set the mixed signal mixed with the optical volume pulse wave and the dynamic noise If each BPF is performed while measuring a predetermined number of cycles, and the optical volume pulse wave cannot be extracted from the mixed signal on which the BPF is performed, the mixed signal on which the BPF is performed is deleted and the optical volume pulse wave is removed from the mixed signal on which the BPF is performed. The apparatus relates to a heart rate measuring apparatus using optical volume pulse wave, characterized in that after storing the extracted optical volume pulse wave, if it can be evicted, performing the above process by a predetermined period and quantity, and transmitting the averaged amount to the linked mobile device. .

It is possible to use in real-time telemedicine or u-Health field without the inconvenience or pain by utilizing the heart rate measuring device using optical volume pulse wave, a non-invasiv method that can be worn at all times during daily life or exercise. Do.

In addition, the present invention can be implemented at low cost by using a heart rate measurement method using a non-invasiv method of light volume pulse wave can provide a popular real-time health care system that can be used by everyone.

In addition, it is possible to transmit the real-time heart rate measurement data to the desired place by interlocking the heart rate measurement device with a personal mobile device, so that it can be used in parallel with not only the personal fitness field such as exercise but also the remote medical field.

1 is a block diagram of a heart rate measuring apparatus using a photo-plethysmograph (PPG)
2 is a block diagram of an example of a signal input unit of a heart rate measuring apparatus using a photo-plethysmograph (PPG)
Figure 3 is a flow chart for the function of the heart rate measurement device using a photo-plethysmograph (PPG)
[Figure 4] Flow chart for the heart rate measuring device function without using the DB

Hereinafter, with reference to the accompanying drawings and description will be described in detail the operating principle of the preferred embodiment of the present invention. However, the drawings and the following description shown below are for the preferred method among various methods for effectively explaining the features of the present invention, the present invention is not limited only to the drawings and description below.

In addition, preferred embodiments of the present invention to be carried out below are provided in each system functional configuration to efficiently describe the technical components constituting the present invention, or system functions that are commonly provided in the technical field to which the present invention belongs. The configuration will be omitted, and described mainly on the functional configuration to be additionally provided for the present invention.

1 is a block diagram of an apparatus 100 for measuring heart rate using a photo-plethysmograph (PPG).

The controller 105 stores information about an exercise type (walking, jogging, biking, skiing, etc.) in advance and allows a user to select and use an exercise type previously stored in the heart rate measuring apparatus 100. When the user selects a pre-stored exercise type from the mobile device 125 linked with the heart rate measuring apparatus 100 and transmits the pre-stored exercise type to the control unit 105, the control unit 105 uses the signal input unit 200 according to the exercise type selected by the user. Of the light sources 210, 215, and 220 of the light source 210, 215, and 220, which are optimal for the motion type, such as a light source 1 or a light source 2 or a light source 3, or a combination of light sources 1 to 3 that are used. Minimize the effects of copper noise. In addition, the control unit 105 prepares for use by searching in advance for the movement noise data for each exercise type previously stored in the movement noise DB 120 according to the exercise type selected by the user.

The signal input unit 200 receives the optical volume pulse wave and transmits the optical volume pulse wave to the comparator 110, and the comparator 110 receiving the optical volume pulse wave from the signal input part 105 performs band pass filtering on the optical volume pulse wave. BPF) and then determine whether the optical volume pulse wave is a general heartbeat signal with no noise or whether it contains dynamic noise but whether it is a recognizable signal and whether it is a mixed signal that includes dynamic noise. The optical volume pulse wave is transmitted to the control unit 105 when there is no general heartbeat signal or dynamic noise included but recognizable signal. If the optical volume pulse wave is a mixed signal that is difficult to recognize because it contains a dynamic noise, the dynamic noise DB 120 recognizes by removing the dynamic noise signal from the mixed signal that is difficult to recognize in comparison with the previously stored dynamic noise samples for each motion type. This possible volumetric pulse wave signal is converted and transmitted to the control unit 105. The control unit 105 that receives the optical volume pulse wave signal from the comparator 110 stores the received optical volume pulse wave signal in the storage and transmission unit 115 or uses a wired / wireless communication method. (125)). In addition, the control unit 105 receives the data transmitted from the storage and transmission unit 115 in order to update the content of the dynamic noise DB 120 in the interlocked mobile device 125, the dynamic noise DB 120 ) Function.

FIG. 2 is a block diagram of an example of the signal input unit 200 of the heart rate measuring apparatus 100 using the photo-plethysmograph (PPG), and the heart rate measuring apparatus 100 using the optical volume pulse wave (PPG). It will be apparent to those of ordinary skill in the art that the quantity and location of the light sources 210, 215, and 220 and the quantity and location of the light receiver 225 may vary according to the intended use of .

An exercise type such as walking does not include much noise in the light volume pulse wave compared to an exercise type having a lot of movement such as jogging or skiing. In addition, wearing the heart rate measuring device 100 on the ear or forehead portion is significantly less affected by the noise than wearing on the wrist or ankle. If the movement type or the heart rate monitor wearing position is not much movement as described above, the controller 105 uses the quantity of the light sources 210, 215, 220 as the minimum quantity and the movement is performed. In the case where many types of exercise or the position of wearing the heart rate monitor are affected by a lot of dynamic noise, the light sources are set by the type of exercise type and the wearing position of the heart rate monitor 100 which are preset to use the light sources 210, 215, and 220. The use of 210, 215, and 220 is controlled by the controller 105. The light receiving unit 225 receives a reflection signal (light volume pulse wave) of red light or near infrared light irradiated to arterial blood near the skin from a light source and transmits it to the comparator 110.

Figure 3 is a flow chart of the function of the heart rate measurement device using a photo-plethysmograph (PPG).

When the user selects an exercise type in a mobile device that is linked with the heart rate measuring device (300), the mobile device transmits information about the exercise type selected by the user to the heart rate measuring device controller and transmits the information about the exercise type. The received control unit completes the exercise preparation by supplying power to the light sources to be used among the light sources of the signal input unit (305). The heart rate measuring device measures the optical volume pulse wave at a predetermined period (310). It is determined whether the volumetric pulse wave is a general heartbeat signal without dynamic noise or a mixed signal containing dynamic noise but recognizable signal and whether the volumetric pulse wave includes dynamic noise (315). If the normal heartbeat signal is missing or if the noise is included but the signal is recognizable, the measured optical volume pulse wave is stored and (325) If the measured optical volume pulse wave is a mixed signal that is difficult to recognize due to dynamic noise, the pre-stored dynamic noise in the dynamic noise DB is stored. In comparison with the sample (355), the dynamic noise signal is removed from the mixed signal that is difficult to recognize, and converted into a recognizable optical pulse wave signal (360), and then stored in the control unit or transmitted to a pre-set mobile device. (325) Check whether there is an exercise end command in the mobile device linked with the heart rate measuring device (330) If the exercise end command is received (335) and ends the operation of the heart rate measuring device (345) If the exercise end command received If there is no (340), the optical volume pulse wave measurement process is repeatedly performed at each preset time period (310).

4 is a flow chart of a heart rate measurement device function without using a congested DB.

When the user selects an exercise type in the mobile device that is linked with the heart rate measuring device (400), the mobile device transmits information on the exercise type selected by the user to the heart rate control unit and transmits the information about the exercise type. The received control unit selects light sources to be used among the light sources of the signal input unit (405), and also calculates the optical volume pulse wave measurement period (the number of optical volume pulse waves to be measured before transmitting to the linked mobile device) and transmission period by motion type. (410) The heart rate measuring apparatus performs BPF while measuring the mixed signal of the optical volume pulse wave and the dynamic noise by a predetermined amount in a predetermined period (415), and the optical signal from the mixed signal that performs the BPF If the volumetric pulse wave cannot be evicted, the mixed signal on which the BPF is performed is discarded. If the optical volume pulse wave can be extracted from the mixed signal on which the BPF has been performed, the extracted optical volume pulse wave is stored, and the above-described procedure is performed by the final period and quantity, and averaged and transmitted to the interlocked mobile device.

Claims (5)

The method for measuring heart rate by irradiating red or near-infrared light to arterial blood close to the skin to obtain a mixed signal including light volume pulse wave and dynamic noise and extracting the light volume pulse wave from the obtained mixed signal
Selecting an exercise type from a mobile device linked with the heart rate measuring device and transmitting the exercise type to the heart rate measuring device; And
Measuring an optical volume pulse wave at a heart rate measuring apparatus based on the exercise type received from the mobile device; And
And transmitting the measured optical volume pulse wave (heart rate data) to a pre-connected mobile device. The method of claim 1
And removing the optical noise from the mixed signal measured by the signal input unit, extracting the optical volume pulse wave, and transmitting the optical volume pulse wave to the controller. The method of claim 1
Selectively controlling a light source (a combination of light source 1 or light source 2 or light source 3 or light source 1 to 3) selected from the light sources of the signal input unit by the control unit according to the motion type selected by the user; Heart rate measurement method using a light volume pulse wave, characterized in that further comprises a. The method of claim 1,
Storing and managing data on the dynamic noise generated by the exercise type and transmitting the dynamic noise data to the comparator to extract the optical volume pulse wave from which the dynamic noise signal is removed from the mixed signal measured by the signal input unit. Heart rate measurement method using the optical pulse wave. The method of claim 1
Setting a light volume pulse wave measurement cycle for each exercise type (the number of light volume pulse waves to be measured before transmitting to a linked mobile device) and a transmission cycle in order to implement heart rate measurement for each exercise type without using the DB; And
During the measurement period, it is determined whether the optical volume pulse wave can be extracted from the mixed signal including the optical volume pulse wave and the dynamic noise, and if it is impossible to extract the optical volume pulse wave, the measured mixed signal is removed and the extraction of the optical volume pulse wave is performed. If possible, extracting a light volume pulse wave from the measured mixed signal; And
After performing the optical volume pulse wave measurement process by the predetermined period and quantity, heart rate measurement using optical volume pulse wave, characterized in that it comprises the step of transmitting the measured optical volume pulse wave to a mobile device linked or stored Way.

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