KR20080073531A - Wearable bio-signal detecting system - Google Patents

Abstract

A wearable bio-signal measuring system is provided to facilitate wearing without direct harm to a human body, to obtain electrical stability, and to measure bio-signals in an unconstrained state. A wearable bio-signal measuring system includes a wearable signal detecting module(10) and a signal analysis system(20). The wearable signal detecting module is worn on a human body to detect a volume change of the abdomen. The signal analysis system displays a signal received from the wearable signal detecting module. The wearable signal detecting module has at least a capacitance signal detecting unit(100). The capacitance signal detecting unit is composed of two capacitive electrodes(110,120) to detect the volume change of the abdomen during respiration and a capacitive sensor(150) to detect and output a capacitance signal from signals received from the two capacitive electrodes after A/D conversion.

Description

Non-contact wearable bio-signal detecting system {Wearable bio-signal detecting system}

1 is a block diagram schematically illustrating the configuration of a wearable wireless biosignal measurement system of a non-contact type according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a low pass filter in the microprocessor of FIG. 1.

3 is a block diagram illustrating a high pass filter in the microprocessor of FIG. 1.

4 is an example of a wearable wireless biosignal measuring system of the present invention.

5 illustrates a state in which the wearable signal detection module of FIG. 4 is actually worn.

6 is another example of the wearable wireless biosignal measurement system of the present invention.

7 is an example of the results measured by the wearable wireless biosignal measurement system of the present invention.

8 is an explanatory diagram illustrating that the wearable wireless biosignal measuring system of the present invention can be provided in a garment form.

<Description of Major Symbols in Drawing>

10: wearable signal detection module 20: signal analysis system

100: capacitance signal detection unit 110, 120: capacitive electrode

150: capacitive sensor 200: microprocessor

300: transmitter 400: receiver

500: signal analysis unit

The present invention relates to a non-contact wearable wireless biosignal measuring system capable of real-time monitoring of biosignals such as blood flow and respiration of a human body using capacitive electrodes and sensors.

As the society develops, not only is the population dying from respiratory diseases due to air pollution and increased smoking rates due to stress, but also the cases of suffocation of infants and toddlers due to carelessness of new parents. Therefore, in case of a patient with a respiratory disease or a disabled person or infant who is unable to cover his or her own body, it is easy to wear it anytime and anywhere to measure breathing in real time, and immediately warn the guardian or the doctor of the hospital if there is an abnormality in breathing. There is a need for a biosignal measurement system that enables the use of a biosignal.

In addition, in order to integrate the ubiquitous medical system, there is a need for a biosignal measurement system that can be easily worn and monitored in real time, and can achieve electrical stability.

However, until now, adequate real-time respiration measurement system is lacking.

Therefore, the present invention uses the fact that the capacitance between the capacitive electrode changes according to the exhalation and inspiration, the contactless wearable wireless biosignal measuring system that can measure the normal presence of the intake and exhalation through the change of the capacitance To provide. In addition, the biosignal measuring system of the present invention is easy to wear and can be monitored in real time, and has electrical stability.

The capacitive sensor and the electrode used in the present invention are electrically stable in a non-contact manner, and unlike other conventional types of biological electrodes, even if worn for a long time, they do not directly harm the human body and are small and simply attached to clothes. It is possible to measure the bio-signals easily in the unrestrained state by the wearable of the belt or belt type. Also, the bio-signals measured by the Bluetooth wireless communication module can be measured in real time using a computer or a PC. It can be conveniently checked on an ultra mobile PC.

Therefore, the present invention is easy to wear, it is possible to measure the bio-signal, such as breathing and blood flow in real time in patients suffering from blood flow disorders or respiratory diseases, disabled people who are difficult to cover their own body, or infants in the neonatal intensive care unit It is possible to provide immediate emergency treatment by sending the abnormality of the measured signal to the guardian or the attending physician of the hospital, and to measure the vital signs unconditionally when checking the health status of the general public or athletes who are exercising. You can check the health status of firefighters in real time.

The technical problem to be achieved by the present invention is to provide a non-contact wearable wireless bio-signal measurement system that can monitor in real time the bio-signals, such as blood flow and respiration of the human body using a capacitive electrode and sensor.

Another technical problem to be achieved by the present invention is easy to wear, can be monitored in real time, has electrical stability, does not harm the human body even if worn for a long time, can measure the signal in an unrestrained state The present invention provides a non-contact wearable wireless biosignal measurement system.

Another technical problem to be solved by the present invention is to measure bio signals such as respiration and blood flow in real time in a patient suffering from a blood flow disorder or respiratory disease, a disabled person who is unable to cover his or her body, or an infant in the intensive care unit of a newborn. In addition, the present invention provides a non-contact wearable wireless biosignal measurement system that transmits an abnormality of a measured signal to a guardian or a doctor of a hospital to enable immediate emergency treatment.

Hereinafter, the configuration and operation of a wearable wireless biosignal measuring system of a non-contact type according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram schematically illustrating a configuration of a wearable wireless biosignal measurement system of a non-contact type according to an exemplary embodiment of the present invention, and includes a wearable signal detection module 10 and a signal analysis system 20. . The wearable signal detection module 10 includes a capacitance signal detection unit 100, a microprocessor 200, and a transmission unit 300, and the signal analysis system 20 includes a receiver 400 and a signal analyzer 500. It consists of.

The wearable signal detection module 10 is a module worn on the human body to detect a volume change of the abdomen and transmit the detected signal to the signal analysis system 20.

The capacitance signal detecting unit 100 detects a volume change of the abdomen when breathing, that is, detects a breathing related signal, and includes two capacitive electrodes 110 and 120. The capacitance signal detection unit 100 detects a signal from the two capacitive electrodes 110 and 120, and A / D converts the signal and outputs the signal. The capacitance signal detector 100 may be formed of two capacitive electrodes 110 and 120 and a capacitive sensor 150.

Capacitive electrodes 110 and 120 are electrodes formed by inserting a thin conductive thin film between insulating films. Aluminum foil may be used as the conductive thin film.

The capacitive sensor 150 detects the capacitance signal from the signals received from the two capacitive electrodes 110 and 120, and A / D converts the signal and outputs the signal. The capacitive sensor 150 may use QT300 (QUANTUM Co., Ltd.), and the QT300 is a sensor for measuring capacitance through a switching method. It is composed of one IC so that no separate amplifier stage is required, and the measured capacitance is converted into a digital value. The output eliminates the need for an A / D converter, making it ideal for wearable systems that require simplicity. The QT300 outputs a capacitance sampling frequency of 41Hz and a capacitance conversion digit value of 16 bits. In some cases, in the present invention, the capacitive sensor 150 may be replaced by an amplifier, an A / D converter, a microconcrete unit (MCU), or the like.

The microprocessor 200 removes high frequency noise from the output signal of the capacitive sensor 150 and outputs it to the transmitter 200. The microprocessor 200 is configured to remove high frequency component noise with a digital low pass filter and to remove low frequency component noise with a digital high pass filter. The PIC16F74 may be used as the microprocessor 200. A digital low pass filter of the microprocessor 200 may use a 45 Hz 10th order FIR low pass filter, and the digital high pass filter of the microprocessor 200 may use a 0.75 Hz first order IIR high pass filter to remove the baseline. Low frequency component noise can be removed.

The transmitter 200 wirelessly transmits an output signal of the microprocessor 200. The transmitter 200 may be a blue pitcher transmitter.

That is, the wearable signal detection module 10 attaches the capacitive electrodes 110 and 120 to both sides of the abdomen, and uses the capacitive sensor 150 connected to the capacitive electrodes 110 and 120 to provide the abdominal capacitance. After the measurement, the measured digital signal is received by the microprocessor 200 and undergoes a digital signal processing to remove the high frequency noise signal, and wirelessly transmits the data that has undergone the digital signal processing through the transmitter 300. The wearable signal detection module 10 including the capacitance signal detection unit 100, the microprocessor 200, and the transmission unit 300 is a belt type or a garment type that is mounted on the body. The wearable signal detection module 10 may be driven by embedding a battery (not shown) in itself.

The signal analysis system 20 processes and displays a signal received from the wearable signal detection module 10.

The receiver 400 wirelessly receives a signal transmitted from the transmitter 200 and outputs the signal to the signal analyzer 500. The receiver 400 may be a Bluetooth receiver.

The signal analyzer 500 displays the output signal of the receiver 400, stores the data, and calculates the respiratory rate (respiratory rate per minute). The signal analyzer 500 may be formed of a computer or an ultra mobile PC.

In the present invention, in the relationship between the respiration mechanism and the capacitance of the human body, the capacitance of the capacitor composed of two electrode plates, that is, the capacitive electrode around the insulating material, that is, the output value of the capacitive sensor 150 is the following equation 1 Determined by

Where C is the capacitance of the capacitor consisting of two electrode plates (capacitive electrodes), X is the distance between the electrodes, A is the area of the electrode plate, ε ₀ is the dielectric constant, and ε _r is the relative dielectric of the material Is a constant. In particular, ε ₀ in free space may be (1 / 36π) × 10 ^-9 .

When the capacitive electrode plate is attached to both sides around the abdomen, the gap X between the electrode plates changes with respect to the volume change caused by respiration, thereby changing the capacitance value. In addition, air entering the body during inspiration changes the relative dielectric constant of the abdomen, resulting in a change in capacitance.

FIG. 2 is a block diagram illustrating a low pass filter in the microprocessor of FIG. 1.

The microprocessor 200 used a 45 Hz 10 th order FIR low pass filter to remove high frequency component noise, and the FIR low pass filter is described in FIG. 2.

As shown in FIG. 2, the FIR filter is a filter having a non-recursive characteristic that performs filtering with only finite values of an input signal.

Where X is the input, Y is the output, n is the order, and b is the coefficient of the filter.

The FIR filter has a disadvantage in that a time delay is increased as the order is higher. However, since the FIR filter has no feedback component, the linear phase characteristic, that is, the waveform shape between the input and the output is well maintained and always stable.

3 is a block diagram illustrating a high pass filter in the microprocessor of FIG. 1.

The microprocessor 200 used a 0.75 Hz first order IIR high pass filter to remove low frequency component noise, and the description of the IIR high pass filter is shown in FIG. 3.

In the IIR high pass filter, filtering is performed by recursively or feedbacking the values of the input signal and the output signal, and can be expressed by Equation 3 below.

Where X is the input, Y is the output, n is the order, and a and b are the coefficients of the filter.

Since the IIR filter has a nonlinearity, the input and output waveforms are not similar to each other, and the system stability cannot be guaranteed. However, the IIR filter can realize a fast attenuation characteristic with a lower order than the FIR filter.

4 is an example of a wearable wireless biosignal measuring system of the present invention, and FIG. 5 shows a state in which the wearable signal detection module of FIG. 4 is actually worn.

4 illustrates an example of a wearable signal detection module 10 that is a transmitting side and a signal analysis system 20 that is a receiving side in a wearable wireless biosignal measurement system. The wearable signal detection module 10 is configured to be wound around the abdomen. The capacitive electrode of the wearable signal detection module 10 is not mounted on the outer surface of the bag but is mounted therein so that the capacitive electrode does not directly contact the skin.

6 is another example of the wearable wireless biosignal measurement system of the present invention.

6 is a wearable signal detection module 10 is mounted on the belt, the capacitive electrode of the wearable signal detection module 10 is inserted in the middle of the belt so as not to contact the skin.

7 is an example of the results measured by the wearable wireless biosignal measurement system of the present invention.

As a result of measuring a change in capacitance during breathing (expiration and inspiration) using the capacitive electrode in the wearable wireless biosignal measurement system of the present invention, the result is shown in FIG. 7. This is the same as using the thermistor which is mainly used for respiration measurement.

8 is an explanatory diagram illustrating that the wearable wireless biosignal measuring system of the present invention can be provided in a garment form.

In the wearable wireless biosignal measurement system of the present invention, the wearable signal detection module 10 is mounted on a garment, and a capacitive electrode is embedded between the inner and outer shells of the garment in the wearable signal detection module 10. That is, it can be said to be a garment containing a capacitive electrode.

The present invention is not limited to the above described and illustrated in the drawings, and of course, more modifications and variations are possible to those skilled in the art within the scope of the following claims.

As described above, the wearable wireless biosignal measurement system of the present invention is a non-contact method, it is possible to monitor the biological signals such as blood flow and respiration of the human body in real time using the capacitive electrode and sensor, it is easy to wear It is equipped with electrical stability, does not harm the human body even if worn for a long time, it can measure the signal in an unrestrained state.

In addition, the non-contact wearable wireless biosignal measurement system of the present invention is a real-time breathing and blood flow, such as in patients with blood flow disorders or respiratory diseases, disabled people difficult to cover their own body, or infants in the neonatal intensive care unit The biosignal can be measured, and the abnormality of the measured signal is transmitted to the guardian or the doctor of the hospital to enable immediate emergency treatment.

In other words, the capacitive sensor and the electrode used in the present invention are electrically stable in a non-contact manner, and do not directly harm the human body, unlike other types of biological electrodes, even if worn for a long time. In addition, the wearable signal detection module 10 of the present invention can be miniaturized, can be easily attached to clothes, and can easily measure a bio-signal in a non-restrained state as a wearable (wearable) of a bag, belt or belt type. can do. In addition, the biological signal measured using the wireless communication module can be conveniently confirmed in real time by the signal analysis unit 500 made of a computer (PC) or an ultra mobile computer (ultra mobile PC).

Accordingly, the wearable wireless biosignal measuring system of the present invention is worn by a wearable signal detection module 10 to a patient suffering from blood flow disorder or respiratory disease, or to a disabled person who is unable to cover his or her own body, or a neonatal intensive care unit. It is possible to measure vital signs such as breathing and blood flow in real time in infants and infants, and transmits the abnormality of the measured signal to the guardian or the attending physician of the hospital to enable immediate emergency treatment. When checking the health status, it is possible to measure the vital signs unconditionally, and to check the health status of the firefighters in real time.

In particular, the present invention can measure the bio-signals such as respiration, blood flow, etc. using a capacitive electrode and capacitive sensor, and can be easily worn, real-time monitoring and electrical stability, grafting into a ubiquitous medical system This is possible.

Claims (19)

In the non-contact wearable wireless bio-signal measuring system consisting of a wearable signal detection module that is worn on the human body to detect a volume change of the abdomen, and a signal analysis system for displaying a signal received from the wearable signal detection module, The wearable signal detection module Two capacitive electrodes for detecting volume changes of the abdomen upon respiration; A capacitive sensor for detecting, A / D converting, and outputting a capacitance signal from the signals received from the two capacitive electrodes; Wearable wireless bio-signal measurement system of a non-contact type, characterized in that it comprises at least a capacitance signal detection unit made of. In the non-contact wearable wireless bio-signal measuring system consisting of a wearable signal detection module that is worn on the human body to detect a volume change of the abdomen, and a signal analysis system for displaying a signal received from the wearable signal detection module, The wearable signal detection module A capacitance signal detector for detecting a volume change of the abdomen upon respiration and outputting the digital signal; A microprocessor that removes noise by digitally filtering the signal received from the capacitance signal detector; A transmitter for wirelessly transmitting an output signal of the microprocessor; Wearable wireless biosignal measurement system of a non-contact type, characterized in that consisting of. A capacitance signal detecting unit having two capacitive electrodes and detecting a volume change of the abdomen upon respiration and outputting the digital signal; A microprocessor that removes noise by digitally filtering a signal received from the capacitance signal detector; A transmitter for wirelessly transmitting an output signal of the microprocessor; A receiver for wirelessly receiving a signal transmitted from the transmitter; A signal analyzer which displays an output signal of the receiver; Wearable wireless bio-signal measurement system of a non-contact type, characterized in that it comprises a. The method of claim 2 The capacitance signal detection unit is a wearable wireless bio-signal measurement system of a non-contact type, characterized in that it comprises two capacitive electrodes. The method according to claim 1 or 3 or 4, The capacitive electrode is a wearable wireless bio-signal measurement system of a non-contact type, characterized in that a thin conductive thin film is inserted between the insulating film. The method according to claim 1 or 3 or 4, The capacitive electrode is a wearable wireless bio-signal measurement system of a non-contact type, characterized in that made of aluminum foil. The method according to claim 3 or 4, The capacitance signal detection unit And a capacitive sensor for detecting, A / D converting and outputting a capacitance signal from the signals received from the two capacitive electrodes. The method of claim 7, wherein The capacitive sensor is a wearable wireless bio-signal measurement system of a non-contact type, characterized in that the QT300. The method of claim 1, The wearable signal detection module The contactless wireless wearable signal measuring system of claim 1, further comprising a microprocessor for digitally filtering the signal received from the capacitance signal detector to remove noise. The method according to claim 2 or 3 or 9, And the microprocessor includes a digital low pass filter. The method of claim 10, The cut-off frequency of the digital low pass filter is 45Hz non-contact wearable wireless biosignal measurement system, characterized in that. The method according to claim 2 or 3 or 9, The microprocessor includes a non-contact type wearable wireless biosignal measurement system comprising a digital high pass filter. The method of claim 12, And a cutting frequency of the digital high pass filter is 0.7 Hz. The method of claim 3, The transmitter is made of a blue pitcher transmitter, The receiver is a wearable wireless bio-signal measuring system of a non-contact type, characterized in that consisting of a blue permeable receiver. The method of claim 3, The signal analysis unit wearable wireless bio-signal measurement system of a non-contact type, characterized in that for obtaining the respiratory rate from the output signal of the receiver. The method according to any one of claims 1 to 4, The wearable signal detection module of the wearable wireless bio-signal measuring system of a non-contact type, characterized in that mounted on the bag. The method according to any one of claims 1 to 4, The wearable signal detecting module of the non-contact type, wherein the wearable signal detection module is mounted on a belt. The method according to any one of claims 1 to 4, The wearable signal detecting module of the non-contact type wearable wireless biosignal, characterized in that mounted on the garment. The method according to claim 1 or 3 or 4, The capacitive electrode is a wearable wireless bio-signal measurement system of a non-contact type, characterized in that is mounted so as not to directly contact the skin.

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