KR20170051716A - Menthod for Error Detecting of EEG Signal using Dry Electrodes - Google Patents

Abstract

The present invention relates to a method for detecting an error of an EEG signal using a dry electrode, which includes the steps of: measuring resistance between a reference electrode and an EEG electrode part to minimize contact impedance by checking a contact state with each other; sensing a non-contacted EEG electrode part by giving an individual ID to each EEG electrode part; determining a measurement error when the measured EEG signal is compared with a reference signal to determine a frequency signal other than an EEG signal region; giving a warning if an error time is measured over a predetermined time; and stopping the collection of the EEG signals, thereby achieving a purpose to reduce power consumption through power management.

Description

[0001] The present invention relates to an electroencephalogram (EEG)

In the present invention, a dry electrode is used to measure an EEG signal to minimize hair noise, to obtain a cleaner EEG signal, to transmit the EEG signal to analyze the EEG signal, and to detect an error such as a contact error of the measured EEG signal And more particularly, to a method of detecting an error of an EEG signal using a dry electrode.

Generally, EEG measured in the scalp is used in various industrial fields such as medical, games, and aids for the disabled in recent years.

A wet electrode is generally used to measure EEG signals. Such a wet electrode has a small contact resistance. However, since it requires a scalp treatment such as applying a conductive gel and cutting a part of hair before measuring brain waves, it is very inconvenient, There is a problem of rising.

A dry electrode capable of solving the disadvantages of the wet electrode has been developed. However, the dry electrode of the related art still has a contact resistance as high as that of the wet electrode, so it is difficult to measure the EEG, and it is difficult to measure the EEG occurring in a wide range .

The active dry electrode module 10 includes a housing 11, an active dry electrode 20, a low noise amplifier 13, and a connection frame 14, And an active dry electrode 20 penetrating through the inside of the housing 11 to be engaged with or detached from the test cap, .

A plurality of active dry electrodes 21, 22, 23, 24, 25, 26 may be coupled to the housing 11 in parallel.

As described above, since the conventional dry electrode module 10 according to the related art has a spike needle formed radially at the end of the electrode pin contacting the scalp, the contact resistance can be lowered and the area of measurement can be increased.

However, since the dry electrode module according to the related art has to use a cap, when the electrode module is unstable when worn, the contact impedance is increased and the signal quality is deteriorated.

Domestic patent registration No. 10-1552269 (Notice date: September 10, 2015)

Therefore, according to the present invention, it is possible to check the contact between the reference electrode and the EEPROM by measuring the resistance between the reference electrode and the EEPROM, minimize the contact impedance, assign an ID to each EEG electrode, , The EEG signal is compared with the reference signal to determine that it is a measurement error when it is judged as a frequency signal other than the EEG signal area, and when the error time is measured for a predetermined time or longer, The present invention provides a method of detecting an error of an EEG signal using a dry electrode that reduces power consumption through management.

In order to accomplish the object of the present invention, an error detection process of an EEG signal using a dry electrode is performed by collecting EEG signals from a plurality of EEG electrodes measuring electrical EEG signals by contacting the subject's scalp, A method for detecting errors in an EEG signal using a dry electrode configured as a base, the EEG method comprising: a first step of measuring an EEG signal from a scalp of an examinee through an electrode; A second step of monitoring a contact error state of the EEG electrode part by an electrode contact confirmation part built in each EEG electrode part; A third step of outputting the EEG signal and the contact error detection signal measured in the first and second processes to the EEPROM; A fourth step of checking whether a contact error detection signal is input through the third process; A fifth step of comparing the EEG signal outputted from each of the EEG electrodes with the reference signal after the signal processing and judging whether the EEG signal is erroneous or not; And a sixth step of determining that an EEG measurement error is detected if a contact error detection signal in the fourth step is input or when an EEG signal error is determined in the fifth step and the normal EEG signal is not measured for a predetermined time period; And a control unit for controlling the operation of the control unit.

In the method of detecting an EEG signal using the dry electrode according to the present invention, an elastic body such as a spring is formed inside the electrode, thereby enabling safe contact with the scalp of the subject, minimizing the noise factor due to hair, And the signal output unit is formed in the form of a one chip so that the volume can be minimized. Thus, it is possible to achieve weight reduction and miniaturization, and an individual identification number (ID) And it is possible to confirm the part not in contact with the scalp, and to alert the user if a contact error occurs during the set time, or to power down the EEG device to reduce power consumption.

In addition, since the contact error of the dry electrode is monitored and the measured EEG signal is compared with the reference signal to determine the measurement error, various measurement errors can be prevented.

FIG. 1 is a configuration diagram of an active dry type electrode module according to the related art,
FIG. 2 is an overall block diagram of an EEG apparatus using a dry electrode for implementing the present invention,
FIG. 3 is a detailed block diagram of each block of FIG. 2,
FIG. 4 is an external view of the EEG electrode unit in FIG. 3,
5 is a flowchart illustrating an error detection process of an EEG measurement signal using a dry electrode according to an embodiment of the present invention.

The construction and operation of error detection of a brain wave measurement signal using a dry electrode according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a schematic block diagram of an apparatus for measuring EEG using a dry electrode for realizing the present invention. Referring to FIG. 2, there are shown a plurality of EEG electrode units 101 to 103 for measuring an electric EEG signal in contact with a scalp of a subject. A brain wave measuring unit 200 for acquiring EEG data by collecting EEG signals from the EEG electrode units 101 to 103 and an EEG signal receiving unit for receiving EEG signals from the EEG base unit 200 through wireless communication, And an EEG analyzing apparatus 300 for analyzing the state of the subject.

Here, each of the EEP electrodes 101 to 103 and the EEPROM 200 transmits a signal through SPI (Serial Peripheral Interface) communication.

In addition, the EEG electrodes 101 to 103 are preferably connectable from one channel to sixteen channels.

In addition, the brain wave measuring device 200 supplies driving power to the respective EEG electrodes 101 to 103.

The electrode rod 110 is fixed to an end of an electrode foot 111 having an elastic body (not shown) therein.

The EEG analyzing apparatus 300 may be a personal computer (PC) equipped with an EEG analysis program or a smart device such as a smart phone or a tablet PC. EEG signals are received by wireless communication.

FIG. 3 is a detailed block diagram of FIG. 2. Referring to FIG. 3, each of the EEG electrodes 101 to 103 includes an electrode rod 110 fixed to an end of a plurality of electrode feet 111 to measure a potential change at a measurement position, A contact confirmation unit 120 for sensing a measurement signal of the electrode rod 110 and determining that the contact error is measured at a level lower than a reference level, an amplifier / filter unit (not shown) for amplifying and filtering the electric signal sensed by the electrode rod 110 An ADC 140 for converting an electrical signal from the amplifier / filter unit 130 and a contact confirmation signal from the contact confirmation unit 120 into a digital signal; And an SPI-type signal output unit 150 for transmitting a digital signal from the digital conversion unit 140 to the brain wave measuring device 200. [

The contact confirmation unit 120, the amplification / filter unit 130, the analog / digital conversion unit 140, and the signal output unit 150 of each of the EEG electrodes 101 to 103 are formed of one chip, And the connector unit 160 is connected to the brain wave measuring device 200 using an FPC cable or the like.

FIG. 4 is an external view of the EEG electrode unit shown in FIG. 3, which includes an electrode foot 111 for supporting a rod of an electrode 110 that contacts the scalp. The EEG electrode 101, And a connector 160 connected to the base 200.

The EEPROM 200 includes a microprocessor (MCU) 210 for collecting electric signals transmitted from the signal output units 150 of the EEP electrodes 101 to 103 and acquiring EEP signals according to a stored algorithm A wireless communication unit 220 for wirelessly transmitting EEG signals collected from the MCU 210 to the EEPROM 300 and a power supply 230 for supplying driving power to the EEPROM And a reference signal unit 240 for providing a reference signal of the brain waves to the MCU 210.

A method of determining an EEG signal error using a dry electrode according to an embodiment of the present invention will now be described in detail with reference to FIGS. 2 to 5. FIG.

First, a plurality of EEG electrodes 101 to 103 are fixed to the scalp of the examinee through the respective electrodes 110 and connected to the EEG base unit 200 through the connector unit 160.

The power supply unit 230 of the brain wave measuring device 200 supplies driving power to the respective parts of the brain-wave electrode units 101 to 103. The electrode rod 110 of each of the EEG electrodes 101 to 103 receiving the driving power from the EEG base unit 200 starts to detect electric signals from the subject's scalp.

That is, a change in potential is detected from the electrode rod 110 by a power source applied from the power source unit 230 and output to the amplification / filter unit 130. The amplification / filter unit 130 amplifies the potential change to a predetermined level, To obtain a stable signal.

In this case, since the signal of the EEG is very small, ranging from tens of nanometers to several hundreds of microns,

The filter unit implements a 60 Hz notch filter generated from the power source and is composed of a low pass filter (LPF) of 100 Hz in order to cut out a range outside the EEG region.

The electrical signal output from the amplifying / filtering unit 130 is converted into a digital signal by the A / D converter 140 and output to the EEPROM 200 through the signal output unit 150.

If the normal electrical signal is not detected by the electrode 110, the touch sensing unit 120 senses the electrical signal and transmits the serial peripheral interface (SPI) signal through the analog / digital conversion unit 140 and the signal output unit 150. [ And transmits it to the brain wave measuring device base 200 in a communication manner.

The plurality of EEPROMs 101 to 103 connected to the EEPROM 200 measures the EEPROM signals and transmits them to the EEPROM 200.

The brain wave measuring unit 200 receives signals from the brain wave electrode units 101 to 103 and calculates brain wave data in real time through a signal processing process according to an algorithm stored in the MCU 210.

The MCU 210 collects EEG signals from the signal output unit 150 of each of the EEG electrodes 101 to 103 and determines whether the EEG signal of the subject is correctly input.

In other words, when the EEG reference signal received from the reference signal unit 240 is compared with the measured EEG signal in real time to judge the EEG signal as a frequency signal other than the fluctuation of the EEP and the EEG signal area, If it is measured more than the set time, the collection of EEG signals will be stopped.

In another embodiment of the EEG signal contact error determination, the MCU 210 analyzes the contact confirmation signal from the contact confirmation unit 120 of each EEG electrode 200, Stop.

The MCU 210 transmits the EEG data collected and calculated from the EEG electrodes 101 to 103 to the EEG analyzing unit 300 through the wireless communication unit 220. When the EEG error is detected, An EEG signal collection error signal is transmitted to the EEPROM 300 to generate an alarm message.

Hereinafter, terms and words used in the specification and claims should not be construed as limited to ordinary or dictionary terms, and should be construed as a concept of beauty that meets the technical idea of the present invention. Accordingly, the embodiments described herein and the drawings depicted in the drawings are merely the most preferred embodiments of the present invention and are not intended to represent all of the technical aspects of the present invention, so that various modifications It is to be understood that equivalents and modifications are possible.

100 to 103: Electroencephalogram electrode 110: Electrode
111: electrode foot 120: contact confirmation part
130: amplification / filter unit 140: analog / digital conversion unit
150: Signal output section 160: Connector section
200: EEG base unit 210: Microprocessor
220: wireless communication unit 130:
240: reference signal portion

Claims (5)

A method for detecting errors in an EEG signal using a dry electrode, which comprises a brain wave measuring unit for acquiring brain wave data by collecting EEG signals from a plurality of EEG electrodes measuring electrical EEG signals by contacting a scalp of a subject,
Wherein each of the EEG electrodes measures EEG signals from the scalp of the subject through an electrode;
A second step of monitoring a contact error state of the EEG electrode part by an electrode contact confirmation part built in each EEG electrode part;
A third step of outputting the EEG signal and the contact error detection signal measured in the first and second processes to the EEPROM;
A fourth step of checking whether a contact error detection signal is input through the third process;
A fifth step of comparing the EEG signal outputted from each of the EEG electrodes with the reference signal after the signal processing and judging whether the EEG signal is erroneous or not; And
A sixth step of determining that a contact error detection signal in the fourth step is input or an EEG signal error in the fifth step is an EEG measurement error when a normal EEG signal is not measured for a predetermined time; And detecting an EEG signal using the dry electrode. The method according to claim 1,
Wherein the fourth to sixth steps are performed in a microprocessor of the EEG base unit. The method according to claim 1,
Wherein the measured EEG signal is amplified to a predetermined level through an amplifying and filtering unit and is converted into a digital signal after noise is removed to transmit the signal to the EEG measurement unit using the dry electrode. Error detection method. The method according to claim 1,
Wherein the EEG signal is output to the EEP analyzer when it is determined to be an EEP measurement error in addition to the sixth process. The method according to claim 1 or 4,
And if it is determined that the EEG measurement error is generated in the sixth step, the collection of EEG signals is stopped.

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