Synchronous and rapid forehead electroencephalogram and myoelectricity acquisition patch and acquisition method thereof

Abstract

The invention discloses a flexible single-lead electroencephalogram and myoelectricity synchronous and rapid acquisition patch and an acquisition method thereof, and belongs to the technical field of wearable sensing. The device comprises a microprocessor, a 50Hz wave trap, an electroencephalogram acquisition module, a myoelectricity acquisition module, a power supply module, a wireless transmission module, a signal acquisition electrode and a driving circuit. According to the method, single-channel forehead skin electric signal collection is achieved through the device, rapid separation of electroencephalogram signals and electromyographic signals is achieved based on a self-designed filter circuit of the patch device, and the purpose of extracting two electrophysiological signals through single-time electric signal collection is achieved. The size of the acquisition system is reduced, and meanwhile, two electrophysiological signals are preprocessed. Meanwhile, based on the patch design of the flexible circuit board, wearable detection of electrophysiological signals is achieved, and the defects that traditional myoelectricity and electroencephalogram detection equipment is too large in size and poor in portability, and the action of a testee is limited are overcome.

Description

[0001] This application is a divisional application. The original application was entitled "A Flexible Single-Channel Electroencephalogram (EEG) and Electromyogram (EMG) Synchronous Rapid Acquisition Patch and Acquisition Method Thereof", with application number 202410615992.2 and application date of May 16, 2024. Technical Field

[0002] This invention relates to the field of wearable sensing technology, and in particular to a flexible single-channel electroencephalogram (EEG) and electromyogram (EMG) synchronous rapid acquisition patch and its acquisition method. Background Technology

[0003] Electroencephalography (EEG) signals are weak, low-frequency physiological signals with voltage amplitudes ranging from 0.5µV to 200µV. They are spontaneous electrical potentials generated by neural activity in the brain and contain a wealth of information about brain activity. Portable prefrontal cortex single-lead EEG extraction has been widely used in medical, scientific research, and entertainment scenarios, including health monitoring, emotion recognition, and EEG interfaces. Recording EEG signals can provide data analysis for disease diagnosis and emotion recognition. Prefrontal cortex single-lead EEG systems allow for long-term monitoring with minimal impact on subject activity and have been successfully used in various applications.

[0004] Surface electromyography (EMG) signals are among the most readily acquireable electrophysiological signals of various bioelectrical signals. By placing electrodes on the skin surface, the weak potential difference generated by muscle contraction can be recorded. This weak potential signal is then amplified and converted by an EMG acquisition circuit to form a processable surface EMG signal. Due to its advantages of being non-invasive, safe, convenient, and reliable, it has wide applications in rehabilitation medicine, human-computer interaction, and clinical diagnosis.

[0005] Currently, electromyography (EMG) and electroencephalography (EEG) acquisition involves separate analog amplification, filtering, and analog-to-digital conversion on relatively independent channels. This results in large-sized testing devices, high power consumption, and limited subject movement during testing, and also makes EMG and EEG signals prone to interference. To address these issues, designing a small, portable, wearable device that uses a single-lead electrode in the prefrontal cortex to acquire and separate EMG signals has significant practical importance and application value. Summary of the Invention

[0006] The purpose of this invention is to provide a flexible single-channel simultaneous rapid acquisition patch for EEG and EMG and its acquisition method. EEG and EMG are acquired simultaneously through a single channel. By utilizing the different effective frequencies of the two signals, the separation of EEG and EMG is achieved, enabling the extraction of two target electrical signals in a single acquisition. This reduces the size of the acquisition system while allowing for the preprocessing of the two different signals in the subsequent host computer.

[0007] To achieve the above objectives, the present invention provides a flexible single-channel EEG and EMG synchronous rapid acquisition patch, including a microcontroller for controlling the drive circuit and the EEG and EMG acquisition and processing module, acquiring EEG and EMG data and transmitting the data to a host computer via a wireless transmission module;

[0008] Signal acquisition electrodes and driving circuits; the patch electrodes are designed to acquire surface physiological electrical signals.

[0009] A 50Hz notch filter is used to filter out power frequency noise and reduce its interference with the signal acquisition process.

[0010] The EEG acquisition module includes an EEG acquisition chip, an analog-to-digital converter chip, and an EEG acquisition circuit, which is used to acquire EEG signals and transmit the acquired EEG signal data to a microcontroller.

[0011] The electromyography (EMG) acquisition module includes a bandpass filter and a two-stage amplifier circuit, which are used to filter the EMG signals and transmit the acquired EMG signal data to the microcontroller.

[0012] The power module, which includes a battery interface and a voltage regulator circuit, is used to convert the battery voltage to power the microprocessor, EEG acquisition chip circuit and operational amplifier circuit.

[0013] The wireless transmission module, which includes a Bluetooth chip and wireless transmission circuitry, is used to transmit EEG and EMG data to a host computer.

[0014] Preferably, the voltage regulator circuit consists of a combination of two linear voltage regulator chips.

[0015] Preferably, the EEG acquisition chip, the analog-to-digital converter chip, and the microprocessor constitute the EEG signal acquisition system. The analog front end of the EEG acquisition chip and the microcontroller use the SPI communication protocol, and the analog-to-digital converter chip and the microcontroller use the I2C communication protocol.

[0016] Preferably, the electromyography signal acquisition system consists of a bandpass filter and a two-stage amplifier circuit, an analog-to-digital converter chip, and a microprocessor.

[0017] Preferably, the bandpass filter and secondary amplifier circuit, analog-to-digital converter chip, microprocessor and wireless transmission module are integrated on the same circuit board, which is made of a flexible material that is harmless to the human body.

[0018] A method for rapid simultaneous acquisition of flexible single-channel EEG and EMG data includes the following steps:

[0019] S1. Real-time separation of EEG and EMG based on flexible substrate circuit design;

[0020] S2. EEG and EMG signals are acquired simultaneously through a single channel, and the filtering circuit of the patch device enables rapid separation of EEG and EMG signals, achieving the goal of extracting two electrophysiological signals from a single electrical signal acquisition.

[0021] S3. The flexible patch reduces the size of the acquisition system while performing preprocessing of two electrophysiological signals, making the acquisition device portable and wearable.

[0022] A flexible single-channel EEG / EMG synchronous rapid acquisition patch and its acquisition method can be applied in wearable EEG / EMG acquisition products.

[0023] Therefore, the flexible single-channel EEG / EMG synchronous rapid acquisition patch and its acquisition method using the above-described structure of the present invention have the following beneficial effects:

[0024] (1) Currently, devices used to collect EEG and EMG signals are generally large in size and require wired transmission during signal acquisition. This greatly restricts the subject's movement, seriously interferes with the setting of test conditions, and introduces power frequency interference, affecting the reliability of the signal. Therefore, using miniaturized detection circuits and wireless transmission for data transmission can avoid these problems. At the same time, flexible circuit boards make it possible for subjects to wear the device under their skin. Using such miniaturized wearable devices, EEG and EMG data can be collected without affecting the subject's daily activities.

[0025] (2) Compared with previous EEG and EMG signal acquisition devices, which had problems such as being too bulky, not portable, and expensive, the EMG acquisition device of the present invention is more flexible and convenient to use. It is small in size, portable, and has a flexible circuit board that can be worn on the skin, making it easier for subjects to wear.

[0026] (3) Existing EEG and EMG acquisition systems are all single electrical signal acquisition devices. In this invention, EEG and EMG are acquired simultaneously through a single channel. By taking advantage of the different effective frequencies of the two, EEG and EMG are separated, and two target electrical signals are extracted in one acquisition. This reduces the size of the acquisition system while enabling the preprocessing of the two different signals in the subsequent host computer.

[0027] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the overall structure and flow of a flexible single-channel EEG / EMG synchronous rapid acquisition patch and its acquisition method according to the present invention.

[0029] Figure 2 This is an isometric structural schematic diagram of a flexible single-channel EEG / EMG synchronous rapid acquisition patch and its acquisition method according to the present invention;

[0030] Figure 3 This is a schematic diagram of a 50Hz notch filter circuit for a flexible single-channel EEG / EMG synchronous rapid acquisition patch and its acquisition method according to the present invention.

[0031] Figure 4 This is a schematic diagram of the EEG acquisition module circuit of a flexible single-channel EEG and EMG synchronous rapid acquisition patch and its acquisition method according to the present invention.

[0032] Figure 5 This is a schematic diagram of the electromyography (EMG) acquisition module circuit of a flexible single-channel EEG / EMG synchronous rapid acquisition patch and its acquisition method according to the present invention.

[0033] Figure 6 This is a pin diagram of the STM32 microcontroller used in the present invention for a flexible single-channel EEG / EMG synchronous rapid acquisition patch and its acquisition method. Detailed Implementation

[0034] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0035] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0036] Example

[0037] like Figure 1 As shown, the present invention provides a flexible single-channel EEG and EMG synchronous rapid acquisition patch, including a microcontroller (MCU), model STM32F103C8T6, used to control the drive circuit and the EEG and EMG acquisition and processing module, to acquire EEG and EMG data and transmit the data to the host computer through a wireless transmission module.

[0038] Signal acquisition electrodes and driving circuits: The patch electrodes are designed to acquire surface physiological electrical signals.

[0039] A 50Hz notch filter is used to filter out power frequency noise and reduce its interference with the signal acquisition process.

[0040] The EEG acquisition module includes an EEG acquisition chip (KS1092), an analog-to-digital converter (ADC), and EEG acquisition circuitry. It is used to acquire EEG signals and transmit the acquired signal data to a microcontroller. The microcontroller (STM32) communicates with the ADC via I2C to read signals. Communication between the STM32 microcontroller and the KS1092 chip is achieved using the SPI communication protocol.

[0041] The electromyography (EMG) acquisition module includes a bandpass filter and a two-stage amplifier circuit. These circuits filter the EMG signals and transmit the acquired EMG signal data to the microcontroller. Compared to commonly used digital filters, the bandpass filter and two-stage amplifier circuit offer higher efficiency and conversion stability.

[0042] The power module, including a battery interface and voltage regulator circuitry, converts the battery voltage to power the microprocessor, EEG acquisition chip circuitry, and operational amplifier circuitry. The voltage regulator circuitry consists of two linear voltage regulator chips.

[0043] The wireless transmission module, which includes a Bluetooth chip and wireless transmission circuitry, is used to transmit EEG and EMG data to a host computer.

[0044] The EEG acquisition chip, analog-to-digital converter chip, and microprocessor constitute the EEG signal acquisition system. The analog front end of the EEG acquisition chip communicates with the microcontroller using the SPI protocol, while the analog-to-digital converter chip communicates with the microcontroller using the I2C protocol.

[0045] The electromyography (EMG) signal acquisition system consists of a bandpass filter, a two-stage amplifier circuit, an analog-to-digital converter chip, and a microprocessor.

[0046] The bandpass filter and secondary amplifier circuit, analog-to-digital converter chip, microprocessor and wireless transmission module are integrated on the same circuit board, which is made of flexible material that is harmless to the human body.

[0047] like Figure 2 As shown, the system uses a standard FPC interface with flexible insulating materials such as PI and PET films, which are harmless to the human body. The flexible single-channel EEG / EMG synchronous rapid acquisition patch can be bent and adhered to the subject's forehead after being connected to a power source, making it easy for the subject to wear and use. After fixation, skin electrical signals are acquired through signal acquisition electrodes and a driving circuit, enabling the separation of EEG and EMG signals through this device.

[0048] like Figure 3 The diagram shows the circuit diagram of a 50Hz notch filter. A 50Hz notch filter can filter out power frequency noise and reduce its interference with the signal acquisition process.

[0049] A method for rapid simultaneous acquisition of flexible single-channel EEG and EMG data includes the following steps:

[0050] S1. Real-time separation of EEG and EMG based on flexible substrate circuit design;

[0051] S2. EEG and EMG signals are acquired simultaneously through a single channel, and the filtering circuit of the patch device enables rapid separation of EEG and EMG signals, achieving the goal of extracting two electrophysiological signals from a single electrical signal acquisition.

[0052] S3. The flexible patch reduces the size of the acquisition system while performing preprocessing of two electrophysiological signals, making the acquisition device portable and wearable.

[0053] A flexible single-channel EEG / EMG synchronous rapid acquisition patch and its acquisition method can be applied in wearable EEG / EMG acquisition products.

[0054] like Figure 4 As shown, the KS1092 chip in the EEG acquisition module integrates a low-noise amplifier, filter, internal reference, high-precision low-dropout linear regulator, and reference bias circuit. The chip features an equivalent input noise as low as 1μV and common-mode noise rejection of approximately 100dB. Paired with a high-resolution analog-to-digital converter chip and controlled by a microcontroller via SPI communication to configure the amplification factor, it achieves EEG signal acquisition and amplifies and filters the raw signal.

[0055] like Figure 5 As shown, the EMG acquisition module uses operational amplifiers to form a Sallen-Key filter circuit with cutoff frequencies of 150Hz and 20Hz. This filter circuit forms a bandpass filter circuit from 20Hz to 150Hz, covering the main energy frequency band of the EMG signal. The inverting amplifier circuit boosts the filtered EMG signal to the sampling range of the microcontroller's ADC. The amplification factor of the circuit can be adjusted according to the strength of the target signal.

[0056] like Figure 6 As shown, the microcontroller needs to use the SPI interface to set the gain of the KS1092 chip in the EEG acquisition module. It uses the I2C bus communication protocol to connect to the high-precision analog-to-digital converter (ADC). The ADC sends the processed digital signal to the STM32. The STM32 processes the data and then sends it to the host computer via a serial interface. The STM32 connects to the Bluetooth chip via the TX and RX pins of its serial port, and finally, the Bluetooth chip completes the information exchange with the host computer.

[0057] Therefore, this invention employs a flexible single-channel EEG / EMG synchronous rapid acquisition patch and its acquisition method to achieve the acquisition of single-channel forehead skin electrical signals. Based on a self-designed filtering circuit of the patch device, it achieves rapid separation of EEG and EMG signals, realizing the goal of extracting two electrophysiological signals in a single electrical signal acquisition. This reduces the size of the acquisition system while enabling preprocessing of both electrophysiological signals. Furthermore, the patch design based on a flexible circuit board enables wearable detection of electrophysiological signals, overcoming the drawbacks of traditional EMG and EEG detection devices being too bulky, lacking portability, and restricting the subject's movement.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A forehead electroencephalography and electromyography synchronous rapid acquisition patch, characterized in that, The device comprises: a flexible substrate made of flexible insulating material, which is attached to the forehead skin; a signal collection electrode for collecting physiological electrical signals on the forehead skin surface; a 50 Hz notch filter for filtering out the interference of power frequency noise on the signal collection process; an EEG collection module containing a KS1092 chip, an analog-to-digital conversion chip and an EEG collection circuit, which communicates with the microcontroller through the SPI protocol; the EEG collection module is used to extract and collect EEG signals from physiological electrical signals, convert the collected EEG signal data and transmit it to the microcontroller; the KS1092 chip internally integrates a low-noise amplifier, a filter, an internal reference, a high-precision low-dropout linear regulator and a reference bias circuit; an EMG collection module containing a 20-150 Hz band-pass filter circuit and a two-stage amplification circuit, which is used to filter EMG signals and transmit the collected EMG signal data to the microcontroller; A microcontroller is connected with the EEG signal extraction module and the EMG signal extraction module respectively, used to dynamically configure the gain of the EEG acquisition chip through SPI protocol, and read the converted digital signal through I 2 C protocol. a power module including a linear voltage regulator circuit, which is used to power the microcontroller, EEG signal extraction module and EMG signal extraction module; a Bluetooth module connected to the microcontroller, which is used to wirelessly transmit the processed EEG and EMG data to the host computer; The signal collection electrode, 50 Hz notch filter circuit, EEG signal extraction module, EMG signal extraction module, microcontroller, power module and wireless transmission module are all integrated on the flexible substrate to form an integrated flexible patch device, which realizes single-channel synchronous collection and real-time separation of forehead physiological electrical signals.

2. The forehead electroencephalogram and electromyogram synchronous rapid acquisition patch of claim 1, wherein, The KS1092 chip adopts SPI communication protocol between the analog front end and the microcontroller, and the analog-digital conversion chip adopts I 2 C communication protocol.

3. The forehead electroencephalogram and electromyogram synchronous rapid acquisition patch of claim 1, wherein, The flexible substrate is made of PI or PET film.

4. A collection method of a forehead electroencephalogram and electromyogram synchronous rapid collection patch, applied to the forehead electroencephalogram and electromyogram synchronous rapid collection patch of any one of claims 1-3, characterized in that, The device comprises: attaching a flexible substrate to the forehead skin of a user; collecting physiological electrical signals on the forehead skin through the signal collection electrode; suppressing power frequency noise of the physiological electrical signals through the 50 Hz notch filter circuit; parallelly inputting the noise-suppressed signals to the EEG signal extraction module and EMG signal extraction module; extracting and converting EEG signals through the hardware circuit of the EEG signal extraction module; extracting and amplifying EMG signals through the band-pass filter circuit of the EMG signal extraction module; reading the processed EEG signals and EMG signals through the microcontroller and sending them to the host computer through the wireless transmission module.

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