CN116236205A

CN116236205A - Multichannel miniature brain electricity acquisition system

Info

Publication number: CN116236205A
Application number: CN202211632898.5A
Authority: CN
Inventors: 蔡雨; 许敏鹏; 钟子平; 张泽旭; 叶阳阳; 李辉; 明东
Original assignee: Tianjin University
Current assignee: Tianjin University
Priority date: 2022-12-19
Filing date: 2022-12-19
Publication date: 2023-06-09
Also published as: CN117017306A

Abstract

The invention discloses a multichannel miniature electroencephalogram acquisition system, which can comprise a plurality of single-channel electroencephalogram acquisition devices, a data tag synchronization device and terminal equipment, wherein the single-channel electroencephalogram acquisition devices and the first two modules form a single-channel miniature electroencephalogram acquisition system, and the circuits of the two systems can comprise a circuit for acquiring the electroencephalogram of a low-power BLE MCU for logic control and data transmission; the hair clip structure can be fixed on the scalp through the hair clip structure design of the device and used together with an auxiliary electrode with viscosity; the miniature single-channel electroencephalogram acquisition device is provided with a replaceable direct-connection electrode; the data tag synchronization device based on the double serial ports is used for receiving the stimulation tag information sent by the stimulation program and sending the synchronized data tag to the upper computer respectively. The invention has the characteristics of low power consumption, miniaturization and portability, is convenient to wear, reduces the complexity of acquisition equipment, improves the accuracy of the label, and has higher expansibility and reconfigurability.

Description

Multichannel miniature brain electricity acquisition system

Technical Field

The invention relates to the technical field of electroencephalogram acquisition equipment, in particular to multichannel miniature electroencephalogram acquisition equipment which is convenient to wear, small in size and easy and convenient to operate.

Background

The traditional desk type electroencephalogram acquisition device is widely applied to laboratories. Because of the large volume and heavy weight, the commercial power is required for power supply, the industrial frequency interference exists, and the method can only be applied to indoor experiments. The traditional bench type electrode is often used as a collecting electrode, and conductive paste needs to be sprayed between the electrode and the scalp before experiments, so that the scalp and the electrode can keep good contact, and the contact impedance is reduced. This increases the preparation effort in the early stages of the experiment. Meanwhile, after the experiment is finished, the hair and the electroencephalogram cap also need to be cleaned. The experimental process is complicated. This increases the likelihood of introducing common mode interference or other noise, increasing the complexity of the later data processing, due to the use of long wires to connect the electroencephalogram cap with the amplifier.

In the prior art, although the electroencephalogram signals can be acquired, some traditional acquisition devices are adopted for signal acquisition, and more or less technical problems such as the following are faced when the electroencephalogram signals are acquired.

1) The traditional desk-top brain electricity collection equipment adopts cap type collection electrode often, and is bulky, and the commercial power is supplied power, only can be applied to in the laboratory, can't trend practical application. The portable electroencephalogram equipment has relatively large volume and weight, adopts the fixing modes of a headband, a helmet and the like, has poor secrecy and wearability, and is not easy to be accepted by consumers.

2) The electroencephalogram acquisition apparatus uses long wires to connect electrodes with amplifiers, which increases the likelihood of introducing common mode interference or other noise, increasing the complexity of later data processing.

3) For wireless portable brain wave equipment, when performing stimulus label experiments such as SSVEP, a router and a label box equipment are needed to be matched, so that the complexity of the acquisition equipment is increased.

4) The position of the electroencephalogram cap, the headband and the head-mounted collecting electrode cannot be changed, the experiment is inflexible, and the expandability and the reconfigurability are poor.

Disclosure of Invention

The present invention aims to solve at least one of the technical problems in the related art to some extent.

Therefore, the invention aims to provide a multichannel micro electroencephalogram acquisition system and a multichannel micro electroencephalogram acquisition method, and the invention designs a micro single-channel electroencephalogram acquisition circuit which comprises a low-power BLE MCU for logic control and data transmission, a low-power-consumption program-controlled gain analog acquisition front end for acquiring electroencephalogram signals, a charge pump with positive and negative voltage output for supplying power to each chip and a micro cylindrical battery for supplying power to the system; and a new common mode signal feedback channel is designed, so that the use of lead wires is reduced. The device has the characteristics of low power consumption, miniaturization and portability; the wearing mode of the hairpin structure is designed and combined with the fixing mode of the auxiliary electrode, so that the miniature electroencephalogram acquisition equipment can be fixed on the scalp through the hairpin structure design of the equipment and is matched with the gel electrode with viscosity for use, so that the electrode and the scalp have adhesion, and the hairpin and gel electrode fixing modes are adopted, so that the miniature electroencephalogram acquisition equipment has the characteristics of miniature, secret and strong wearability and is more easily accepted by consumers; the miniature single-channel electroencephalogram acquisition device is provided with the replaceable direct-connection electrode, the replaceable electrode is directly connected with the acquisition circuit by adopting the PCB substrate bonding pad, the possibility that a long wire leads into common-mode interference or other noise is reduced, and meanwhile, the experimental cost is reduced by the replaceable electrode; the electrode form can be wet electrode, dry electrode, gel electrode. The electrode body can be a disc electrode, an elastic copper ball electrode and a sintered silver-silver chloride electrode. The invention designs a data tag synchronization device based on double serial ports, wherein the double serial ports are respectively used for receiving stimulation tag information sent by a stimulation program and sending synchronized data tags to an upper computer. The data tag synchronization device based on the double serial ports reduces the complexity of the acquisition equipment and improves the accuracy of the tag; the invention designs a multichannel electroencephalogram acquisition system based on a miniature single-channel electroencephalogram acquisition device by utilizing a BLE one-master-multiple-slave communication mode. The plurality of miniature single-channel electroencephalogram acquisition devices acquire electroencephalogram data, the positions of the devices can be placed according to standard 10-20 standard leads, and the positions and the quantity can be placed according to experimental requirements, and the design of a connection mode is achieved, so that the device has higher expansibility and reconfigurability.

In order to achieve the above object, an aspect of the present invention provides a multichannel micro electroencephalogram acquisition system, including: the device comprises a plurality of single-channel electroencephalogram acquisition devices, a data tag synchronization device and terminal equipment, wherein the terminal equipment comprises a waveform recording module and a stimulation module;

the stimulation module is used for transmitting stimulation label data to the data label synchronization device through a USB interface when a stimulation signal is generated;

the data tag synchronizing device is used for sending clock synchronizing information and control instructions and receiving the stimulus tag data at the same time;

the plurality of single-channel electroencephalogram acquisition devices are used for receiving the clock synchronization information, acquiring electroencephalogram data according to the control instruction and transmitting the electroencephalogram data to the data tag synchronization device through BLE;

the data tag synchronization device is further used for synchronizing the electroencephalogram data and the stimulation tag data and transmitting the synchronized data and the stimulation tag data to the waveform recording module;

the waveform recording module is used for displaying the waveform of the brain electrical data corresponding to the stimulation label data and storing the data.

In order to achieve the above objective, another aspect of the present invention provides a method for fixing a single-channel electroencephalogram acquisition device, including:

Obtaining a fixing mode of a single-channel electroencephalogram acquisition device; the fixing mode comprises a fixing mode of combining a hairpin wearing structure and an auxiliary electrode; the hairpin wearing structure comprises a hardware fixing structure and a hairpin structure;

according to the fixing mode, the tested hair is clamped by utilizing the grooves of the hairpin structure, the hardware fixing structure and the auxiliary electrode, so that the single-channel electroencephalogram acquisition device is fixed on a scalp to acquire the tested electroencephalogram signals.

In order to achieve the above objective, another aspect of the present invention provides a multi-channel micro electroencephalogram acquisition method, including:

when a stimulus signal is generated, stimulus label data are acquired;

acquiring clock synchronization information to perform clock synchronization, and acquiring a signal acquisition instruction;

after the clock is synchronized, acquiring brain electricity data according to the signal acquisition instruction, and synchronizing the brain electricity data and the stimulation label data;

and acquiring waveforms of the brain electrical data corresponding to the stimulation label data based on the synchronized data and storing the corresponding data.

The multichannel miniature electroencephalogram acquisition system and the multichannel miniature electroencephalogram acquisition method provided by the embodiment of the invention are based on the miniature single-channel electroencephalogram acquisition device, and the wearing and gel fixing combination mode of the hairpin structure is designed, so that the miniature electroencephalogram acquisition device can be fixed on the scalp through the hairpin structure design of the device and is matched with a gel electrode with viscosity for use, so that the electrode and the scalp have adhesion, and the hairpin and auxiliary electrode fixing modes are adopted, so that the miniature electroencephalogram acquisition device has the characteristics of miniature, privacy and strong wearability and is more easily accepted by consumers; and the data tag synchronization device based on the double serial ports reduces the complexity of the acquisition equipment. The brain electrical data and the label information are synchronized by the data label synchronization device, so that the brain electrical data and label information synchronization device has the characteristics of low power consumption, portability, microminiature, secret and the like, and the experimental scene is not limited to a laboratory and is more suitable for outdoor use. The method is more favorable for user acceptance and improves user experience. The multichannel electroencephalogram acquisition system utilizes a BLE-master multi-slave communication mode, a plurality of miniature single-channel electroencephalogram acquisition devices acquire electroencephalogram data, the positions of the devices can be placed in number and in positions according to experimental requirements, and the design of a connection mode is adopted, so that the multichannel electroencephalogram acquisition system has higher expansibility and reconfigurability.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The foregoing and/or additional aspects and advantages of the invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a schematic diagram of a multichannel micro-electroencephalogram acquisition system according to an embodiment of the invention;

FIG. 2 is a schematic diagram of an SSVEP single-channel electroencephalogram experiment based on a dual display according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a single channel micro-electroencephalogram acquisition system according to an embodiment of the present invention;

FIG. 4 is a diagram of a multi-channel micro-electroencephalogram acquisition system architecture according to an embodiment of the present invention;

FIG. 5 is a block diagram of the internal circuitry of a miniature single-channel electroencephalogram acquisition device according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a miniature single-channel electroencephalogram acquisition circuit board according to an embodiment of the invention;

fig. 7 is a schematic diagram of a power panel model of a miniature single-channel electroencephalogram acquisition device according to an embodiment of the invention;

FIG. 8 is a schematic cross-sectional view of a hairpin according to an embodiment of the invention;

FIG. 9 is a schematic diagram of a wearing structure of a hairpin according to an embodiment of the invention;

FIG. 10 is a block diagram of a housing of a miniature single-channel electroencephalogram acquisition device according to an embodiment of the present invention;

FIG. 11 is another block diagram of a housing of a miniature single-channel electroencephalogram acquisition apparatus according to an embodiment of the present invention;

FIG. 12 is a diagram of a hair holding mechanism of a miniature single-channel electroencephalogram acquisition device according to an embodiment of the present invention;

FIG. 13 is a diagram of a hairpin according to an embodiment of the invention;

FIG. 14 is a diagram of a rollover base point structure in accordance with an embodiment of the present invention;

FIG. 15 is a schematic view of an electrode made of different materials according to an embodiment of the invention;

FIG. 16 is a schematic diagram of an alternative electrode according to an embodiment of the invention;

FIG. 17 is a bottom view of an electrode base according to an embodiment of the present invention;

FIG. 18 is a schematic diagram of an electrode structure with a signal input according to an embodiment of the invention;

FIG. 19 is a graph of a Laplace dry electrode with 2 input signal terminals according to an embodiment of the present invention;

FIG. 20 is a block diagram of the internal circuitry of a data tag synchronization apparatus according to an embodiment of the present invention;

FIG. 21 is a schematic diagram illustrating command transmission according to an embodiment of the present invention;

FIG. 22 is a schematic diagram of a dual display based SSVEP single channel electroencephalogram according to an embodiment of the present invention;

FIG. 23 is a schematic diagram of data acquisition of a micro multi-channel electroencephalogram acquisition apparatus according to an embodiment of the present invention;

FIG. 24 is a schematic diagram of a connection of a micro multi-channel electroencephalogram acquisition apparatus according to an embodiment of the present invention;

FIG. 25 is a schematic diagram of an electroencephalogram acquisition flow implemented according to an embodiment of the invention;

FIG. 26 is a schematic diagram of another electroencephalogram acquisition flow implemented according to an embodiment of the invention;

FIG. 27 is a schematic diagram of a co-reference connection of a micro single-channel electroencephalogram acquisition device according to an embodiment of the present invention;

FIG. 28 is a flow chart of a multi-channel micro-electroencephalogram acquisition method according to an embodiment of the present invention;

fig. 29 is a schematic view of the structure of the housing according to the embodiment of the present invention;

fig. 30 is a schematic diagram of another hair clip wearing structure according to an embodiment of the present invention.

Detailed Description

It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other. The invention will be described in detail below with reference to the drawings in connection with embodiments.

In order that those skilled in the art will better understand the present invention, a technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.

The following describes a micro multichannel electroencephalogram acquisition system and method according to an embodiment of the present invention with reference to the accompanying drawings.

Fig. 1 is a schematic structural diagram of a micro multichannel electroencephalogram acquisition system according to an embodiment of the present invention.

As shown in fig. 1, the system 10 includes:

the device comprises a plurality of single-channel electroencephalogram acquisition devices 1, a data tag synchronization device 2 and terminal equipment 3, wherein the terminal equipment 3 comprises a waveform recording module and a stimulation module;

the stimulation module is used for transmitting stimulation label data to the data label synchronization device 2 through the USB interface before a stimulation signal is generated;

the data tag synchronization device 2 is used for sending clock synchronization information and a signal acquisition instruction and receiving stimulation tag data at the same time;

the plurality of single-channel electroencephalogram acquisition devices 1 are used for receiving clock synchronization information, acquiring electroencephalogram data according to signal acquisition instructions and transmitting the electroencephalogram data to the data tag synchronization device 2 through BLE;

the data tag synchronization device 2 is also used for synchronizing the electroencephalogram data and the stimulation tag data and transmitting the synchronized data and the stimulation tag data to the waveform recording module;

and the waveform recording module is used for displaying the waveform of the brain electrical signal corresponding to the stimulation label data and storing the data.

As shown in fig. 2, one test (4) is tested (main test is optional): an electroencephalogram experiment is performed, and a stimulation program (302) for watching a display screen is tested to induce electroencephalogram signals such as SSVEP. (setting and operating the acquisition device by the main test and checking the brain wave shape (301) of the tested; miniature single-channel electroencephalogram acquisition device (1): the data label synchronization device is used for acquiring the brain electrical data and sending the brain electrical data to the data label synchronization device (2) in a BLE mode. The sampling rate can be set to 250Hz-8KHz, and the number can be 32 according to the requirement. Data tag synchronization device (2): the device is communicated with the miniature single-channel electroencephalogram acquisition device (1) through BLE, is communicated with the upper computer (3) through a USB structure, is equivalent to the terminal equipment and is used for receiving a control instruction of the waveform recording program (301) of the upper computer (3) and transmitting the control instruction to the miniature single-channel electroencephalogram acquisition device (1); the method is used for receiving brain electrical data of the miniature single-channel brain electrical acquisition device (1) and a stimulation program (302) of the upper computer (3), synchronizing the labels and the data, and forwarding the label and the data to a waveform recording program (301) of the upper computer (3). Upper computer software (3): comprises a waveform recording program (301) and a stimulating program (302). The waveform recording program (301) is used for recording the brain electrical signal waveform, issuing the control instruction and storing brain electrical data. The stimulation program 302 is used for displaying a stimulation interface, and the stimulation program 302 sends a stimulation label information to the data label synchronization device 2 before the flashing stimulation starts. The waveform recording program (301) may be not limited to the PC side, but may be provided on the mobile phone side or VR side. The stimulation program (302) may not be limited to the PC, but may be on the cell phone, VR, or may be embedded in the device, such as LEDs with different frequencies.

Further, as shown in fig. 3 and fig. 4, a single-channel and multi-channel micro electroencephalogram acquisition system architecture diagram is shown.

Further, the miniature single-channel electroencephalogram acquisition device 1 comprises a miniature single-channel electroencephalogram acquisition circuit, wherein the circuit comprises a low-power-consumption BLE MCU for logic control and data transmission, a low-power-consumption program-controlled gain analog acquisition front end for acquiring electroencephalogram signals, a charge pump with positive and negative voltage output for supplying power to each chip, and a miniature cylindrical battery for supplying power to the system; and a new common mode signal feedback channel is designed, so that the use of lead wires is reduced. The miniature modularized 4-layer PCB design ensures that the volume of the acquisition device is within 1cm < 3 >, and has the characteristics of low power consumption, microminiaturization and portability;

as shown in fig. 5, the miniaturized single-channel electroencephalogram acquisition circuit comprises a main control and wireless transmission module, a signal acquisition module, a power supply module and a lithium battery.

The master control and wireless transmission module is a BLE MCU and a circuit thereof, and is used for reading data acquired by the signal acquisition module, forwarding the data to the data tag synchronization device and monitoring the battery power through BLE, and the master control and wireless transmission module is preferably CC2640R2FRSM. The signal acquisition module is an integrated analog front end acquisition chip and a circuit thereof, and is used for acquiring brain electrical signals, and the analog front end acquisition chip can select an ADS129x series chip of TI, preferably an ADS1291. The sampling rate may be set to 250Hz-8KHz. And the SPI interface is communicated with the master control and wireless transmission module. The signal acquisition circuit adopts a two-wire differential signal design, and the two-wire differential signal is a positive phase input end and a negative phase input end respectively. Further explained is that the two-wire differential signal extends to two points on the housing of the collecting device through the stub wire and the conductive tape or foil, directly connected to the pads of the collecting electrodes. The signal acquisition circuit designs a novel common-mode signal feedback circuit, common-mode interference of differential input signals is fed back to the signal input end through the 2 feedback resistor, and compared with a conventional electroencephalogram acquisition system, the use of one feedback lead wire is reduced. The power module is a voltage converter and a circuit thereof, and the voltage converter converts the voltage of the lithium battery into positive and negative voltages to supply power for the signal acquisition module and the main control and wireless transmission module. The switching voltage is preferably + -2.5V. The voltage converter is preferably TI LM27762. The lithium battery is a rechargeable battery and is connected with the power supply module to supply power for the system. Preferably a cylindrical (button) rechargeable battery.

Further, in order to minimize the volume of the miniaturized single-channel electroencephalogram acquisition circuit system, a 2-block PCB design is preferable, and the length and the width are smaller than 10mm. As shown in fig. 6, the signal acquisition module 609, the main control and wireless transmission module 607 are designed on a PCB, and are preferably packaged with a 0201 resistor and capacitor in a double-sided layout, and the antenna is a small-volume ceramic antenna 608, which is called an acquisition circuit board 601.

The acquisition circuit board 601 is designed to reduce interference/leakage effect and transmission loss of microstrip line, and adopts a multi-layer circuit board, preferably a four-layer board, and the board layer structure is a radio frequency signal layer, a stratum, a power layer and a signal layer.

As shown in fig. 7, the power module 606 is designed on a PCB, and has a size of 10mm by 10mm, which is called a power board 603. The power panel 603 has two pogo pin electrodes 605 for charging electrodes and one toggle switch 604 for system power switch. The power panel 603 is connected with the cylindrical rechargeable lithium battery 602, and converts the cylindrical rechargeable lithium battery 602 into +/-2.5V voltage; the power panel 603 provides ±2.5v voltage for the acquisition circuit board 601, and is connected through 3 thin wires.

Preferably, the invention also designs a fixing method of the single-channel electroencephalogram acquisition device, which comprises the following steps:

according to the fixing mode, the tested hair is clamped by utilizing the grooves of the hair clamping structure, the hardware fixing structure and the auxiliary electrode, so that the single-channel electroencephalogram acquisition device is fixed on the scalp to acquire the tested electroencephalogram signals.

Specifically, the wearing mode of the electroencephalogram acquisition equipment of the miniature single-channel electroencephalogram acquisition device 1 comprises hairpin wearing and auxiliary electrode fixing, the auxiliary electrode can be preferably fixed by using a gel electrode and can also be fixed in an auxiliary manner by using other solid electrodes with viscosity, and it is understood that the auxiliary electrode is used for increasing signal conduction and enhancing the fixing effect. The auxiliary electrode may also be used alone for fixation, because the electrode is light in weight. Only 5g of the conductive paste may be used alone for fixation. The conductive paste such as TEN20 conductive paste may be fixed alone, or the fixation may be performed by fixing the hair alone and adding an electrode having no tackiness. The hairpin wearing structure comprises a hardware fixing structure 8 and a hairpin structure 9. The hardware fixing structure is connected with the acquisition electrode, the fixed internal circuit board and the battery. The hair clamping structure 9 clamps a certain amount of hair 10 through designing a groove containing a sponge adhesive tape, so that the miniature electroencephalogram acquisition equipment is fixed on the scalp, and meanwhile, the miniature electroencephalogram acquisition equipment is matched with a gel electrode with viscosity for use, so that the electrode and the scalp have adhesion. The portable electronic device has the characteristics of miniature size, confidentiality and strong wearability, and is more easily accepted by consumers. The hairpin structure is shown in figure 8.

Further, an example of a hairpin wearing structure is shown in fig. 9.

The hair clip wearing structure 9 includes a hardware fixing structure 8 for connecting the collecting electrode 5, the fixing internal circuit board (601, 603) and the battery 602, and a hair clip structure 9 for fixing the collecting device to the scalp 11 through the hair 10.

The hardware fixing structure is to reasonably layout and fix the collecting electrode, the internal circuit and the battery by designing the shell 8. The hardware fixing mechanism comprises a collecting electrode fixing structure, an internal circuit and a battery fixing structure. As shown in fig. 10.

The housing 8 has an electrode base fixing connection structure, and the present invention designs a groove structure 803 for fixing the electrode 5 having a square base.

The groove structure groove is provided with a conductive adhesive tape or copper foil 804 connected with the signal line of the acquisition circuit board 601. The electrode substrate 501 is pushed into the groove 803, fixing the electrode body 5. The copper foil 804 is connected with the exposed PCB bonding pad at the bottom of the electrode to realize the conduction between the acquisition electrode and the acquisition circuit.

The inner 3 layers of the housing 8 are designed to hold the inner circuit board (601, 603) and the battery 602.

The inside 3 layers of casing 8 are integrated into one piece design, and the centre forms outstanding card structure 807 with fretwork circular design, divide into the three-layer in with the shell, and inside three-layer of casing 8 is placed power supply board 603, battery 602, collection circuit board 601 respectively, and keeps apart power supply board 603, battery 602, collection circuit board 601 are fixed, and card structure 807 opens has rectangle empty slot 806 to be used for through the connecting wire of collection circuit board 601 and power supply board 603. The three-layer structure of the housing may be as shown in fig. 29.

The lower orifice 805 of the housing 8 is a switch interface. The bottom of the housing 8 is provided with a semicircular hole 801 for receiving the two pogo pin electrodes 605 of the power board 603. As shown in fig. 11.

Preferably, as shown in fig. 30, another hair clip wearing structure is designed, and unlike the above, one is a bent structure, and the circle is changed to be similar in shape. The other point is that the structure of the sliding cover fixed with the shell is in an inverted triangle form, so that the stability of the structure is improved.

The back of the housing 8 is provided with 2 rectangular holes 808 for the semi-cylindrical structure 905 of the buckle housing 8 of the hairpin structure 9. The open side of the housing 8 has triangular strip structures 802 on both sides for filling triangular slots 902 of the hair holding mechanism 9 to enclose the housing 8 and secure the hair holding mechanism 9.

The hair clasp 9 has a hair securing structure as shown in fig. 12. As an example, the present invention may fix the micro electroencephalogram acquisition apparatus on the scalp by designing the grooves containing the sponge tape to clamp a certain amount of hair, or may increase the friction between the hair and the acquisition apparatus by other means so that the micro electroencephalogram acquisition apparatus is fixed on the scalp.

The hair clasp 9 is integrally formed, and has triangular slots 902 on two sides of the top, and a fixed connection structure 802 on two sides of the opening side of the casing 8, wherein the fixed connection structure can be a triangular strip structure, a square strip structure or a semicircular structure, so long as the fixed connection structure can be a connection structure with multiple shapes for tightly connecting the fixed connection casing and the hair fixing structure.

The card dispensing structure 9 has a flip base that can be opened to both sides, and a semicircular groove 903 is used in the present invention. A rotating shaft structure of a ring and a cylinder can also be used as a turning base point, as shown in fig. 14.

The hair clamping structure 9 is provided with a hair fixing structure and is used for clamping hair 10, a groove 904 is adopted in the invention, substances with larger friction force are arranged in the groove, and the friction force between the substances and the hair is increased, so that the hair is fixed more firmly. The substance is preferably a sponge tape.

The lower part of the groove 904 is provided with a buckle 906 for clamping the shell 8, and a semi-cylindrical structure 905 is arranged on the buckle and is used for clamping 2 rectangular holes 808 on the back of the shell 8 so as to tightly fix the shell 8 with the hair 11 and the hair fixing mechanism 9. As shown in fig. 13.

The specific step of the wearing mode may be to open the buckle 906 of the card issuing structure 9 to two outer sides, where the buckle 906 may be opened to the outer sides with the semicircular groove as a fulcrum. Proper amount of hair 10 is placed in the groove 904, the height of the collecting device 1 is adjusted by pressing downwards, so that the electrode is in good contact with the scalp, and then the buckle 904 is closed inwards, so that the collecting device 1 is fixed on the scalp.

Furthermore, the miniature single-channel electroencephalogram acquisition device is provided with the replaceable direct-connection electrode, so that the possibility that a long lead leads into common-mode interference or other noise is reduced, and meanwhile, the replaceable electrode reduces the experiment cost; the electrode form can be wet electrode, dry electrode, gel electrode. The replaceable electrode comprises an electrode body and an electrode substrate. The electrode body can be a disc electrode, an elastic copper ball electrode and a sintered silver-silver chloride electrode. As shown in fig. 15. The replaceable direct-connection electrode is provided with a square electrode substrate, the square electrode substrate adopts a PCB design, and the electrode substrate 501 is pushed into the shell 8 to design a groove structure 803 for fixing, so that the replaceable purpose is realized. The direct connection electrode can be replaced, and the electrode substrate is pushed into the shell 8 to design the groove structure 803 to be fixed, so that the exposed PCB bonding pad of the substrate is connected with the copper foil 804 connected with the signal line of the acquisition circuit board 601 in the groove structure 803, and the conduction between the acquisition electrode and the acquisition circuit is realized. The purpose of directly connecting the electrode with the acquisition circuit is achieved. As shown in fig. 16. The replaceable electrode is directly connected with 1 or 2 signal input ends, and can acquire 1 or 2 signals. The replaceable direct-connection electrode has a square base, as shown in fig. 17, the square base adopts a PCB design, and the bottom of the square base is provided with 1 or 2 bare PCB pads 503 according to the number of signal input ends of the electrode, and is conducted with the input signal ends. The electrode with 1 signal input end, for acquiring brain electric signal, the number of required electrodes is 2. The 2 electrodes are respectively connected with the positive input end and the negative input end of 2 differential input signals of the signal acquisition circuit. One of the electrodes is connected to the acquisition circuit positive input via a PCB pad 503 and the other electrode is connected to the acquisition circuit negative input via a short wire, the electrode being devoid of acquisition circuitry. And 2 electrodes are used for realizing the acquisition of brain electrical signals. As shown in fig. 18. The electrode with 2 signal input ends is only needed to collect the brain electric signal. The two input ends of the electrode are respectively connected with the positive phase input end and the negative phase input end of the acquisition circuit through the PCB bonding pad 503, so as to realize the acquisition of the brain electrical signals. The invention preferably has a laplace dry electrode with 2 input signal terminals.

As shown in FIG. 19, the Laplace dry electrode with 2 input signal ends is preferably sintered silver chloride, and the ring and the center of the circle are sintered silver chloride with a certain height, the height ranges from 1mm to 10mm, and the height is preferably 3mm.

Further, the data tag synchronizing device adopts a double serial port design and is respectively used for synchronizing and forwarding data and stimulus tags. The data tag synchronization device is used as a host computer and is communicated with the single-channel electroencephalogram acquisition device through BLE, and is communicated with a waveform recording program and a stimulation program of the upper computer through a USB port. The data tag synchronization device forwards data and instructions to the micro single-channel electroencephalogram acquisition device and the upper computer, synchronizes the electroencephalogram data and the stimulation tag information, and forwards the synchronized electroencephalogram data and the stimulation tag information to waveform recording software of the upper computer.

Specifically, the data tag synchronization device 2 adopts a dual serial port design, and the serial port 1 is used for receiving an instruction issued by the waveform recording program 302 of the upper computer 3 and forwarding the instruction to the micro single-channel electroencephalogram acquisition device; the serial port 2 upper computer 3 stimulates the stimulus label that program 301 sends; and receiving brain electrical data of the single-channel brain electrical acquisition device 1, synchronizing the brain electrical data with the stimulation label, and forwarding the brain electrical data to the upper computer 3 through the serial port 1 for waveform recording program. The stimulus tag can be further described as tag information that different flashing blocks start flashing as in the SSVEP test, and 1,2,3.

As shown in fig. 20, the data tag synchronization device 2 includes a main control and wireless transmission module, a serial port module, and a power module.

The master control and wireless transmission module of the data tag synchronization device 2 is a BLE MCU, and is communicated with the plurality of micro single-channel electroencephalogram acquisition devices 1 through BLE and is used for receiving and synchronizing data of the plurality of micro single-channel electroencephalogram acquisition devices 1. The master control and wireless transmission module can select a CC26xx series BLEMUs, preferably CC2642R. The preferred CC2642R chip can achieve up to 32 lead measurements;

the serial port module of the data tag synchronization device 2 is connected with the main control and wireless transmission module and the PC upper computer 3. And the device is used for forwarding brain electricity data synchronized by the main control and wireless transmission module, a control instruction of the upper computer and a stimulation label.

The serial port module is a double serial port circuit, and the serial port 1 is communicated with the waveform recording program 301 of the upper computer 3 and is used for data transmission and instruction control of acquisition signals. The serial port 2 is in communication with the stimulation program 302 of the upper computer 3 and is used for receiving the stimulation label information. The dual serial circuit may be a multi-serial chip, preferably CH9344, with a baud rate of up to 12Mbps to reduce stimulus tag delay.

The power module adopts a USB port of a PC to provide 5V voltage and provides 3.3V power for the main control and wireless transmission module and the serial port module. Preferably TPS61025DRCR converts a voltage of 5V to a voltage of 3.3V.

The data tag synchronizing device 2 adopts a multi-layer circuit board design, preferably a four-layer board design, for reducing interference/leakage effect and reducing transmission loss of microstrip lines, and the board layer structure is a radio frequency signal layer, a stratum layer, a power supply layer and a signal layer.

Further, the upper computer software: including waveform recording procedures and stimulation procedures. The waveform recording program is used for recording the brain electrical signal waveform, issuing the control instruction and storing brain electrical data. The stimulation program is used for displaying a stimulation interface, and the stimulation program sends a stimulation label message to the data label synchronization device before the flashing stimulation starts. The waveform recording program is not limited to the PC end, and may be at the mobile phone end or the VR end. The stimulation program can be not limited to the PC end, the mobile phone end, the VR end, or embedded end equipment, such as LED flickering with different frequencies. As shown in fig. 21.

The upper computer 3 program comprises a waveform recording program 301 and a stimulating program 302, which can be respectively displayed by a 2-block display and communicated with the data tag synchronization device through a USB port. The waveform recording program 301 receives the electroencephalogram data and the tag information transmitted by the data tag synchronization apparatus through the serial port 1, and performs waveform display and data storage. The user issues instructions to the micro single-channel electroencephalogram acquisition equipment through the waveform recording program 301. The stimulation program 302 is configured to display a stimulation interface for the test, and the stimulation program 302 sends a stimulation tag start message to the data tag synchronization device 2 through the serial port 2 before the flashing stimulation starts.

Further, the multichannel micro electroencephalogram acquisition system utilizes a BLE one-master-multi-slave communication mode. The device comprises a plurality of micro single-channel electroencephalogram acquisition devices, wherein the positions of the micro single-channel electroencephalogram acquisition devices can be placed according to standard 10-20 standard leads, and the micro single-channel electroencephalogram acquisition devices can be placed in quantity and position according to experimental requirements, and the design of a connection mode has higher expansibility and reconfigurability.

Preferably, the novel extensible multi-lead brain electricity acquisition mode based on BLE transmission comprises a plurality of miniature single-channel brain electricity acquisition devices 1, a data tag synchronization device 2 and an upper computer 3.

As shown in fig. 22, the BLE one-master-to-many-slave communication method is utilized, a plurality of micro single-channel electroencephalogram acquisition devices are used as a plurality of slaves, and a data tag synchronization device is used as a master.

The micro single-channel electroencephalogram acquisition devices 1 are communicated with the data tag synchronization device 2 through BLE, the data tag synchronization device 2 is communicated with the upper computer through a USB interface, and data and instructions are forwarded to the micro single-channel electroencephalogram acquisition devices 1 and the upper computer 3. The upper computer 3 includes a waveform recording program 301 and a stimulation program 302 for recording brain electrical data and generating stimulation and stimulation labels, respectively.

A plurality of miniature single-channel electroencephalogram acquisition devices are used as action electrodes for acquiring electroencephalogram data. The plurality of miniature single-channel electroencephalogram acquisition devices simultaneously and sequentially send stimulation tag data and electroencephalogram data to the data tag synchronization device at a certain frequency. The data tag synchronizer transmits the data to a waveform recording program of the upper computer to display waveforms and tag data. The number of the miniature single-channel electroencephalogram acquisition devices can be expanded according to experimental requirements, and at most 32 miniature single-channel electroencephalogram acquisition devices can be arranged. As shown in fig. 23.

The miniature single-channel electroencephalogram acquisition device 1 is used for acquiring scalp electroencephalogram signals, the number of the miniature single-channel electroencephalogram acquisition devices can be selected according to the experimental requirement of measuring the electroencephalogram signals, and the number of the miniature single-channel electroencephalogram signals is more than or equal to 2. The stimulation tag data and the brain electrical data are transmitted to the data tag synchronization device (2) in a BLE mode.

Specifically, the connection form of the multichannel electroencephalogram acquisition device comprises an independent electrode, a monopolar lead, an average lead and a bipolar lead. In an independent electrode acquisition mode, as shown in a of fig. 24, each single-channel electroencephalogram acquisition device adopts a laplace dry electrode with 2 input signal ends, and each single-channel electroencephalogram acquisition device acquires one path of electroencephalogram signal. In the unipolar lead acquisition mode, as shown in b of fig. 24, the electrode adopts an electrode with 1 input signal, the inverting input ends of all acquisition devices are connected to one acquisition electrode without an acquisition circuit, and other acquisition devices output one path of electroencephalogram signal. In the average lead collection mode, as shown in c of fig. 24, the electrode is an electrode with 1 input signal, and the electrode PCB substrate with 1 input signal has an adding resistor connected with two bonding pads. The inverting input ends of all the acquisition devices are connected to an acquisition electrode without an acquisition circuit, the acquisition electrode is not connected with the scalp, and each acquisition device outputs one path of electroencephalogram signal. In the bipolar lead acquisition mode, as shown in d of fig. 24, the electrode is an electrode with 1 input signal, and the inverting input terminal of the former acquisition device is connected with the positive input terminal of the latter acquisition device. Each acquisition device outputs one path of brain electrical signals.

And a BLE-based dual serial port data tag synchronization device. The data tag synchronization device 2 is used for receiving an instruction issued by the waveform recording program 302 of the upper computer 3 and transmitting a stimulation tag sent by the stimulation program 301 of the upper computer 3 to the micro single-channel electroencephalogram acquisition device; the brain electrical data of the plurality of micro single-channel brain electrical acquisition devices 1 and the stimulation labels of the stimulation program 302 are received and synchronized, and forwarded to the upper computer 3 waveform recording program 301. The stimulus tag may be further described as tag information indicating which stimulus box starts flashing as in the SSVEP test, and 1,2,3. The upper computer 3 comprises a waveform recording program 301 and a stimulation program 302, which can be respectively displayed by a 2-block display, and the waveform recording program 301 is used for main test observation of the acquired waveform of the tested brain electrical signal, issuing of a control instruction and storing brain electrical data. The stimulation program 302 is configured to display a stimulation interface for the test, and the stimulation program 302 sends a stimulation tag start message to the data tag synchronization device 2 through the serial port 2 before the flashing stimulation starts.

Example 1:

the experimental equipment is shown in fig. 2, and the flow chart is shown in fig. 25:

1) The micro single-channel electroencephalogram acquisition device 1 is started by starting up and turning on the toggle switch 604.

2) The miniature single-channel electroencephalogram acquisition device 1 is fixed at the tested pillow area by fastening hair. The specific step of the wearing method can be explained by opening the buckles 906 of the hairpin structure 9 to the two outer sides, putting a proper amount of hair 10 into the grooves 904, adjusting the height of the collecting device 1 by pressing downwards, so that the electrodes are in good contact with the scalp, and then closing the buckles 904 inwards, so that the collecting device 1 is fixed on the scalp.

4) The data tag synchronization device 2 is inserted into a computer USB port (main test), the data tag synchronization device 2 is automatically connected with the micro single-channel electroencephalogram acquisition device 1 and performs clock synchronization, and an acquisition starting instruction is set after clock synchronization.

5) (Main test) A waveform recording program 301 is set on one display to select serial port 1, and data tag synchronizer 2 is connected to set a data storage path and name. It is observed whether the electroencephalogram waveform displayed by the waveform recording program 301 is correct.

6) The test is allowed to rest for 1 minute and looks at the stimulus program 302 interface of another display.

7) The (main test) setting waveform recording program 301 starts recording data. And initiates the stimulation program 302.

8) When a certain stimulus block of the stimulus program 302 starts to flash, the corresponding stimulus tag information is sent to the data tag synchronization device 2 through the serial port 2. The stimulation program will display different stimuli at specific times and send different stimulus label data to the data label synchronization means 2.

9) The miniature single-channel electroencephalogram acquisition device 1 sequentially transmits data to the data tag synchronization device 2 at fixed frequency. The data tag synchronization device 2 synchronizes the data and the tag, and then transmits the synchronized data and tag to the waveform recording program 301 via the serial port 1. The waveform recording program 301 displays an electroencephalogram waveform and saves data. The miniature single-channel electroencephalogram acquisition device 1 can acquire data in a circulating mode and send the data to the data tag synchronization device 2.

The miniature single-channel electroencephalogram acquisition system of the embodiment has microminiaturization, portability, comfort and privacy, and can be hidden between hairs during acquisition, so that the acquisition is more favorable for user acceptance and user experience is improved. The connection mode of the acquisition electrode and the acquisition circuit reduces the possibility of introducing common mode interference or other noise. The replaceable electrode is designed, and the replaceable electrode can reduce the experimental cost.

Example 2:

the experimental equipment is shown in fig. 22, and the flow is shown in fig. 26:

1) The toggle switch 604 is turned on to start the plurality of micro single-channel electroencephalogram acquisition devices 1.

2) The device is installed, a plurality of miniature single-channel electroencephalogram acquisition devices 1 are fixed on the scalp to be tested through hair buckling, the fixed positions can be placed by selecting 10-20 standard leads, and the device can also be placed by itself according to experimental requirements. The specific step of the wearing method can be explained by opening the buckles 906 of the hairpin structure 9 to the two outer sides, putting a proper amount of hair 10 into the grooves 904, adjusting the height of the collecting device 1 by pressing downwards, so that the electrodes are in good contact with the scalp, and then closing the buckles 904 inwards, so that the collecting device 1 is fixed on the scalp.

4) The data tag synchronization device 2 is inserted into a computer USB port (main test), the data tag synchronization device 2 is automatically connected with a plurality of miniature single-channel electroencephalogram acquisition devices 1 and performs clock synchronization, and an acquisition starting instruction is set after clock synchronization.

9) The plurality of micro single-channel electroencephalogram acquisition devices 1 sequentially send data to the data tag synchronization device 2 at a fixed frequency. The data tag synchronization device 2 synchronizes the data and the tag, and then transmits the synchronized data and tag to the waveform recording program 301 via the serial port 1. The waveform recording program 301 displays an electroencephalogram waveform and saves data. The plurality of micro single-channel electroencephalogram acquisition devices 1 can circularly acquire data and send the data to the data tag synchronization device 2.

The miniature single-channel electroencephalogram acquisition system of the embodiment has microminiaturization, portability, comfort and privacy, and can be hidden between hairs during acquisition, so that the acquisition is more favorable for user acceptance and user experience is improved. The connection mode of the acquisition electrode and the acquisition circuit reduces the possibility of introducing common mode interference or other noise. The replaceable electrode is designed, and the replaceable electrode can reduce the experimental cost. The multi-lead brain-electricity information of more areas can be recorded, so that the brain recovery intention is more comprehensive and accurate.

Example 3:

the experimental equipment is shown in fig. 22, the connection schematic diagram is shown in fig. 27, an electrode with 1 signal input end is adopted, negative inputs of a plurality of micro single-channel electroencephalogram acquisition devices are led out through short wires and are connected together and placed at the top of the head, the electrode is used as a public reference, the electrode is not provided with an acquisition circuit, and the positions of the micro single-channel electroencephalogram acquisition devices can be placed according to 10-20 standard leads or can be placed by themselves according to experimental requirements.

The flow is as shown in fig. 26:

2) The miniature single-channel electroencephalogram acquisition device 1 is fixed at the scalp by fastening hair, and the fixed position can be placed by selecting 10-20 standard leads or automatically according to experimental requirements. The specific step of the wearing method can be explained by opening the buckles 906 of the hairpin structure 9 to the two outer sides, putting a proper amount of hair 10 into the grooves 904, adjusting the height of the collecting device 1 by pressing downwards, so that the electrodes are in good contact with the scalp, and then closing the buckles 904 inwards, so that the collecting device 1 is fixed on the scalp.

Example 4:

the multi-channel SSVEP wheelchair control experiment based on the LED lamp comprises one tested brain electricity acquisition experiment, a plurality of miniature single-channel brain electricity acquisition devices, one data tag synchronization device and stimulation generation and data processing equipment. The stimulation generating and data processing equipment is arranged at the front end of the wheelchair and faces to a user, the stimulation generating and data processing equipment is based on the FPGA design, 12 LEDs with different flicker frequencies are uniformly distributed at intervals of 30 degrees, the diameter of the LEDs is 20cm, the LEDs are used for indicating the advancing direction and angle, and the middle LED lamp represents stop. The FPGA is provided with an online SSVEP classification system and is used for judging the frequency of SSVEP generated by the acquired electroencephalogram signals so as to determine the advancing direction and angle and then control the wheelchair to advance according to the judged direction.

In use, the user wears 9 active electrodes located in the occipital region and one reference electrode located in the forehead. The data tag synchronization device is connected with the stimulation generation and data processing equipment through the USB port, after the system completes connection and clock synchronization, the buzzer drips 2 sounds to serve as prompts, and then LEDs and the like with different frequencies begin to flash. The user stares at the LED lamp in the direction to be advanced, and the stimulus generating and data processing device processes the data, judges the advancing direction and controls the wheelchair to advance.

Further, motor imagery experiments can be performed to control the wheelchair to move forward or backward, such as imagining left and right hands, feet movement and tongue movement to represent forward, backward, left and right, and stop instructions.

The electroencephalogram acquisition system of the embodiment enables a user to perform activities outdoors, and the acquisition device of the system is small in size and light in weight, so that the burden is not brought to the user. The system adopts BLE to carry out data transmission, and is designed with low power consumption, so that a user can use the system outdoors for a long time. And an extensible multi-lead electroencephalogram experiment can be performed by using a BLE one-master multi-slave communication mode. The electrode position of the invention can be automatically placed according to the requirement, the pillow area can be placed for SSVEP test, and the top area can be placed for motor imagery test.

According to the miniature multichannel electroencephalogram acquisition system provided by the embodiment of the invention, the use of lead wires is reduced, so that the device has the characteristics of low power consumption, miniaturization and portability, is convenient to wear, reduces the complexity of acquisition equipment, improves the accuracy of labels, and has higher expansibility and reconfigurability.

In order to achieve the above embodiment, as shown in fig. 28, a micro multichannel electroencephalogram acquisition method is further provided in this embodiment, including:

s1, when a stimulus signal is generated, acquiring stimulus label data;

s2, acquiring clock synchronization information to perform clock synchronization and acquiring a signal acquisition instruction;

s3, after clock synchronization, acquiring brain electrical data according to a signal acquisition instruction, and synchronizing the brain electrical data and stimulation label data;

and S4, acquiring waveforms of the brain electrical data corresponding to the stimulation label data based on the synchronized data and storing the corresponding data.

According to the miniature multichannel electroencephalogram acquisition method provided by the embodiment of the invention, the use of the lead wire is reduced, so that the device has the characteristics of low power consumption, miniaturization and portability, is convenient to wear, reduces the complexity of acquisition equipment, improves the accuracy of labels, and has higher expansibility and reconfigurability.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

While embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the invention, and that variations, modifications, alternatives and variations may be made to the above embodiments by one of ordinary skill in the art within the scope of the invention.

Claims

1. A miniature multichannel electroencephalogram acquisition system, comprising: the device comprises a plurality of single-channel electroencephalogram acquisition devices, a data tag synchronization device and terminal equipment, wherein the terminal equipment comprises a waveform recording module and a stimulation module;

2. The miniature multichannel electroencephalogram acquisition system of claim 1, the single-channel electroencephalogram acquisition apparatus comprising an acquisition circuit comprising: the system comprises a first main control and wireless transmission module, a signal acquisition module, a first power supply module and a battery module, wherein the signal acquisition module comprises an acquisition circuit board, the acquisition circuit board is used for acquiring brain electrical signals, and the signal acquisition module is communicated with the main control and wireless transmission module through an SPI interface; the first main control and wireless transmission module is used for reading the brain electrical signals acquired by the signal acquisition module and forwarding the brain electrical signals to the data tag synchronization device through BLE; the first power supply module is arranged on the power panel and comprises a voltage converter and a circuit thereof, and the voltage converter converts the battery voltage of the battery module into positive and negative voltages to supply power for the signal acquisition module and the first main control and wireless transmission module; the battery module is connected with the first power module.

3. The micro multichannel electroencephalogram acquisition system according to claim 1, wherein the data tag synchronization device comprises a second main control and wireless transmission module, a serial port module and a second power supply module, and the second main control and wireless transmission module is used for receiving and synchronizing electroencephalogram data acquired by the plurality of single-channel electroencephalogram acquisition devices; the serial port module is connected with the second main control and wireless transmission module and is connected with the terminal equipment; the serial port module comprises a first serial port and a second serial port circuit, the first serial port circuit is communicated with the waveform recording module of the terminal equipment, the first serial port is used for forwarding brain electricity data and acquisition instructions synchronized by the main control and wireless transmission module, the second serial port circuit is communicated with the stimulation module of the terminal equipment, and the second serial port circuit is used for receiving the stimulation label data; the second power module is used for providing power for the second main control and wireless transmission module and the serial port module.

4. The miniaturized multichannel electroencephalogram acquisition system of claim 1 wherein the connection format of the plurality of single channel electroencephalogram acquisition devices comprises individual electrodes, unipolar leads, average leads, and bipolar leads.

5. The fixing method of the single-channel electroencephalogram acquisition device is characterized by comprising the following steps of:

6. The fixing method according to claim 5, wherein the hardware fixing structure comprises a housing, a collecting electrode fixing structure, an internal circuit structure and a battery fixing structure, wherein the collecting electrode fixing structure of the housing is a groove-shaped structure for fixing the replaceable electrode, and a conductive adhesive tape or a copper foil connected with a signal line of the collecting circuit board is arranged in a groove of the groove-shaped structure; the internal circuit structure of the shell is of a three-layer structure, a card structure arranged in the three-layer structure is used for respectively placing a power panel, a battery module and an acquisition circuit board, and a rectangular empty slot is arranged in the card structure and used for placing connecting wires of the acquisition circuit board and the power panel; the battery fixing structure of the shell is used for placing two electrodes of the power panel, one surface of the shell is provided with a rectangular hole, and the rectangular hole is used for being connected with the hairpin structure; the hardware fixing structure is provided with a partition board and a supporting structure at a third layer and is used for fixing the power panel.

7. The fixing method according to claim 6, wherein a fixing connection structure is arranged on one side of the shell, the hair clamping structure is a two-side overturning structure, and the fixing method further comprises a hair fixing structure and an overturning base point structure, wherein the fixing connection structure is used for connecting the hair fixing structure; the overturning base point structure comprises a semicircular groove or a rotating shaft structure; the hair fixing structure is characterized in that the groove is formed in the hair fixing structure, the lower portion of the groove is provided with a buckle used for clamping the shell, and a semi-cylindrical structure is arranged on the buckle and used for enabling the shell, hair and the hair fixing structure to be connected.

8. The method of securing according to claim 6, wherein the replaceable electrode comprises an electrode body and an electrode substrate, the electrode body comprising one of a disk electrode, an elastic copper ball electrode, and a sintered silver chloride electrode; the electrode substrate comprises a square electrode substrate, and the square electrode substrate is a PCB.

9. The method of fixing of claim 8, wherein the replaceable electrode is used to fix the electrode substrate to the slot structure of the housing such that the PCB board is connected to copper foil in the slot structure that is connected to signal lines of the acquisition circuit board.

10. A micro multichannel electroencephalogram acquisition method based on the micro multichannel electroencephalogram acquisition system according to any one of claims 1 to 4, characterized by comprising the steps of:

when a stimulus signal is generated, stimulus label data are acquired;