Distributed wireless high-density surface electromyography synchronous acquisition system

Abstract

The present invention belongs to the field of human-computer interaction. Disclosed is a distributed wireless high-density surface electromyography synchronous acquisition system, which comprises a high-density electromyography front-end acquisition control unit, a base station unit, and an upper computer. The high-density electromyography front-end acquisition control unit and the base station unit are connected via a wireless system for data transmission. The high-density electromyography front-end acquisition control unit comprises a high-density electromyography acquisition array, a reference electrode, and a signal transmission module. The base station unit comprises a synchronous control module, a wireless routing module, and a charging / discharging module. The upper computer serves as a user-end computer program loaded with a signal preprocessing and display module and a high-density electromyography decoding algorithm module. The client acquires and analyzes information received from the base station unit and displays the results. The distributed high-density surface electromyography synchronous acquisition system of the present invention employs a wireless distributed modular design combined with low-noise circuit layout, achieving collaborative acquisition of electromyographic signals from multiple muscle groups with high signal-to-noise ratio, high channel count, and high sampling rates.

Description

A distributed wireless high-density surface electromyography synchronous acquisition system Technical Field

[0001] The present invention belongs to the field of human-computer interaction, and specifically relates to a system for collecting, transmitting and analyzing physiological myoelectric signals on the human body surface, in particular to a wireless synchronous collection and analysis system for distributed high-density surface myoelectric data. Background Art

[0002] Surface electromyography (sEMG) is a bioelectrical signal generated by human neuromuscular activity that can reflect important physiological status and health information. It has the advantages of being non-invasive, non-traumatic, and simple to use. Surface electromyography (sEMG) is typically extracted using a single or dual electrode placed on the muscle belly. However, skeletal muscle activation is uneven during movement, and signal extraction with a limited number of electrode channels can result in signal variations due to electrode placement, making it difficult to accurately analyze muscle activation and estimate muscle force. High-density surface electromyography (HD-sEMG) uses a two-dimensional matrix of surface electrodes covering the entire muscle skin area. HD-sEMG can obtain information about the target muscle in both the temporal and spatial domains, visualizing the corresponding activation areas in the skeletal muscle, overcoming the low spatial resolution of conventional electrodes. As a means of objectively quantifying human physiological electrical signals, HD-sEMG currently has extensive engineering applications in areas such as prosthetic control and intention recognition for human-machine interactions. It also holds broad application prospects in human factors engineering, virtual reality, rehabilitation medicine, and sports training.

[0003] In response to the demand for real-time synchronous acquisition of multiple body parts and multiple motion scenarios, the shortcomings of existing surface electromyography signal acquisition technology are mainly reflected in the following two aspects:

[0004] (1) Facing the wireless demand for high-density surface electromyography data acquisition, it is difficult for traditional wireless acquisition equipment to meet the channel number, sampling frequency and synchronization requirements.

[0005] Li Sujiao and others designed an array-type high-density surface electromyography (EMG) acquisition device. This device uses a self-made 16-channel array-type high-density EMG electrode to collect raw EMG signals, which are converted into digital signals via a multi-channel signal processing module. This digital signal is then transmitted via a Bluetooth-based wireless communication module, enabling the acquisition of 16 channels of EMG signals. Sheng Xinjun and others designed a surface EMG signal acquisition system for motor unit decoding, which uses self-made electrodes to acquire 4 channels of EMG signals. While these methods take into account the ease of wearing the device, they lack the ability to collect EMG signals from a limited number of channels and cannot jointly acquire signals from multiple muscle groups, limiting their practical applications.

[0006] (2) The hardware circuits in existing high-density surface electromyography acquisition solutions are complex and require many components. The high-density electromyography circuits are large in size after integration, making it difficult to meet wearable requirements and the need for real-time synchronous measurement of multiple measurement points during human movement. There is also a problem of poor human adaptability in complex motion environments.

[0007] Zhang Hengyi et al. designed a high-density active flexible electrode array and its signal conditioning circuit. This design employs a two-stage amplifier circuit to amplify and filter myoelectric signals. When used with an NI acquisition card, it can accurately measure single-channel myoelectric signals. Feng Wanyu et al. designed an EMG acquisition device based on flexible active electrodes. This device uses active circuits to transform the impedance of the acquisition channel and filter the channel, enabling precise extraction of a single-channel EMG signal from four electrodes. These aforementioned solutions all focus on acquiring accurate single-channel EMG signals and accurately measuring the EMG signal voltage amplitude by setting resistance, capacitance, and impedance values. Existing acquisition solutions struggle to accurately measure multi-channel EMG signals.

[0008] In response to the above problems, the present invention is committed to developing a new type of wireless high-density surface electromyography data acquisition system with a distributed modular design. The acquisition front end is separated from the signal storage module to ensure the ease of use and low coupling of the equipment; complete the comprehensive optimization design of the internal signal acquisition circuit to achieve high-quality electromyography data acquisition; optimize the real-time transmission and system synchronization functions, and have the characteristics of high channel number, high sampling frequency, strong synchronization, etc.; have a lightweight structural design and good wearability to ensure the stable use of the acquisition device in multiple scenarios; have a synchronous trigger function design, which can realize synchronous acquisition capabilities with other acquisition systems, such as motion capture, EEG systems and other equipment. Technical issues

[0009] This invention aims to address issues such as poor signal quality, limited channels, and insufficient synchronization in electromyography acquisition technology, resulting in poor signal acquisition and user experience. It provides a new distributed wireless measurement solution for high-density surface electromyography (SEM). This approach improves the accuracy of collected high-density SEM signals and broadens their application in brain-computer interfaces, human factors engineering, virtual reality, rehabilitation medicine, and sports training. Technical Solutions

[0010] The technical solution of the present invention:

[0011] A distributed wireless high-density surface electromyography synchronous acquisition system includes a high-density electromyography front-end acquisition control unit, a base station unit, and a host computer. The high-density electromyography front-end acquisition control unit and the base station unit transmit data via a wireless system. The high-density electromyography front-end acquisition control unit includes a high-density electromyography acquisition array, a reference electrode, and a signal transmission module. The base station unit includes a synchronization control module, a wireless routing module, and a charging and discharging module. The host computer is a user-side computer program that is loaded with a signal preprocessing and display module and a high-density electromyography decoding algorithm module. The client collects and analyzes the information received from the base station unit and displays the results.

[0012] During use, the reference electrode is moistened and fixed to the tendon of the human skeletal muscle, the high-density electromyography acquisition array is attached to the belly of the human skeletal muscle, and then the reference electrode and the high-density electromyography acquisition array are respectively connected to the signal transmission module; after the host computer issues an acquisition instruction, the base station unit parses the instruction and controls the high-density electromyography front-end acquisition control unit to start working; wherein, the high-density electromyography acquisition array transmits the skin surface electromyography signal to the signal transmission module, and the signal transmission module packages the signals within the same time period and sends them to the base station unit, and the base station unit integrates the signals transmitted by multiple high-density electromyography front-end acquisition control units, and transmits the signals to the host computer in real time through the data cable; the host computer displays and stores the files.

[0013] Furthermore, the high-density electromyography acquisition array is composed of immersion gold contacts, copper wiring and a polyimide substrate, wherein the immersion gold contacts are located on the polyimide substrate and are led out through the copper wiring; the high-density electromyography acquisition array is distributed and fixed on the belly of each skeletal muscle of the human body through double-sided adhesive foam, wherein the medical double-sided adhesive foam has reserved holes and is filled with conductive paste, and the contacts are in contact with the human skin through the conductive paste, and the electromyography signals on the skin surface are transmitted to the signal transmission module through the conductive paste-contact-copper wiring; the contact size and spacing of the high-density electromyography acquisition array can be freely customized according to the shape of the muscle, and the number of contacts of the same high-density electromyography acquisition array shall not exceed 64; the immersion gold contacts on the high-density electromyography acquisition array are arranged according to the shape of the muscle while ensuring consistent spacing. The contacts adopt the gold-immersion process to improve the corrosion resistance of the contacts against sweat and ensure the stability of the collected electromyographic signals; the polyimide material base has good compatibility with the skin and can be in long-term contact with the skin. It can well integrate the contacts and cables to form a high-density electromyographic acquisition array.

[0014] Furthermore, the reference electrode is fixed at the tendons of various skeletal muscles of the human body and adopts a wristband design; multiple high-density myoelectric front-end acquisition control units share one reference electrode.

[0015] Furthermore, the signal transmission module includes a high-density electromyography acquisition array connector, an electromyography signal processing chip, a microprocessor, a six-axis acceleration sensor, a power control module and a battery module; the high-density electromyography acquisition array connector is connected to the high-density electromyography acquisition array to transmit the original electromyography signal to the signal transmission module; the electromyography signal processing chip is used to amplify and sample the electromyography signal, perform bandpass filtering and analog-to-digital conversion, with a resolution of 16 bits, which can be expanded to 24 bits, and can complete data sampling of 30KSps of 64-channel signals at most; the microprocessor adopts CC3 with integrated dual-band Wi-Fi low-power 5G communication chip The 235S chip integrates the received high-density EMG signals and acceleration signals through multi-channel data integration and real-time control of synchronous signal transmission, ultimately achieving lossless data processing and low-power data communication. The six-axis acceleration sensor integrates a three-axis acceleration sensor and a three-axis gyroscope to capture motion data during the EMG data acquisition process. The power control module and battery module power the high-density EMG front-end acquisition control unit and protect it from power shortages or overloads. A low-dropout linear voltage regulator circuit design is used to reduce the background noise in the collected EMG signals.

[0016] Among them, the high-density electromyography acquisition array transmits the skin surface electromyography signal to the signal transmission module, and the electromyography signal processing chip converts the signal into a digital signal with 24-bit resolution; the six-axis acceleration sensor transmits the acceleration signal to the microprocessor, which simultaneously receives the high-density electromyography signal and the acceleration signal, and packages the signals within the same time period and sends them to the base station unit.

[0017] Furthermore, the synchronization control module sends out timing pulses in the form of broadcasting to notify all high-density electromyography front-end acquisition control units to perform synchronization calibration; the pulse interval is controlled at about 1 second, which can ensure that the time difference in sampling time between each front-end acquisition control unit during the entire sampling process is less than 1 millisecond; the synchronization control module has a synchronization input port and a synchronization output port, wherein the synchronization input port starts the wireless high-density surface electromyography synchronization acquisition system based on the signal input of the external device, and completes the synchronization acquisition with the external device; when the host computer issues a start acquisition command, the synchronization control module will synchronously output a pulse to start the external device through the synchronization output port.

[0018] Furthermore, the wireless routing module is used to receive wireless signals transmitted by the high-density electromyography front-end acquisition control unit and send wireless control signals to the high-density electromyography front-end acquisition control unit; after obtaining the electromyography signal, the wireless routing module transmits it to the host computer through a wired network.

[0019] Furthermore, the charging and discharging module includes a power control module and a lithium-ion battery, which is mainly used for charging the high-density electromyography front-end acquisition control unit; the power control module mainly plays the role of voltage reduction and current stabilization, and the lithium-ion battery is used to store electrical energy, providing energy guarantee for the system when an external power supply is not available.

[0020] Furthermore, the host computer system is a computer program that integrates storage, computing, and display functions, including a signal preprocessing and display module and a high-density electromyography decoding algorithm module; wherein the signal preprocessing and display module realizes the preprocessing of spectrum analysis and display of high-density data, high- and low-pass filtering, motion artifact elimination, bad track detection, and damaged data removal, and passes the data to the high-density electromyography decoding algorithm module; the high-density electromyography decoding algorithm module decomposes the preprocessed high-density electromyography signal based on the blind source separation algorithm, and extracts the activation discharge time series of the motor neurons that control the corresponding movement.

[0021] The established distributed wireless high-density surface electromyography synchronous acquisition system can synchronously acquire up to 640 channels of electromyography data in real time.

[0022] A distributed wireless high-density surface electromyography synchronous acquisition device, comprising

[0023] The high-density myoelectric front-end acquisition control unit includes a high-density myoelectric acquisition array 0101, a signal transmission module 0102, and a reference electrode 0103. The high-density myoelectric acquisition array 0101 is connected to the signal transmission module 0102 via a high-density myoelectric acquisition array connector 0102-1. A high-density myoelectric acquisition array supporting medical double-sided adhesive foam 0101-1 is provided at the bottom of the high-density myoelectric acquisition array 0101.

[0024] Signal transmission module 0102 includes a high-density myoelectric acquisition array connector 0102-1, an acquisition control unit integrated circuit board 0102-2, charging contacts 0102-3, a lithium-ion rechargeable battery 0102-4, a reference electrode interface 0102-5, and a signal indicator light 0102-6. The circuit portion of acquisition control unit integrated circuit board 0102-2 includes an electromyographic signal processing chip, a six-axis acceleration sensor, a microprocessor, and a power management module, and is designed with four layers of copper.

[0025] The base station unit 0200 includes a storage box 0201, a display screen 0202, a charging compartment signal light 0203, a charging compartment 0204, a synchronization input interface 0205, a synchronization output interface 0206, a host computer communication network port 0207, a base station unit charging interface 0208, a base station unit switch 0209, a display screen switch 0210, and a base station unit power indicator light 0211; the storage box 0201 is used to place data cables and a high-density electromyography acquisition array; the display screen 0202 is used to display the operating status information, power usage, signal connection strength, and remaining power of each signal transmission module; the charging compartment signal light 0203 is used to display the power status of the signal transmission module; the charging compartment 0204 is used to charge and store the signal transmission module. The magnetic design inside the compartment can fix the module to ensure stable charging of the device; the synchronization input interface 0205 is connected via BNC The q9 connector is connected to the external device and cooperates with the peripheral device for synchronous acquisition; the synchronous output interface 0206 is connected to the peripheral device to control the peripheral device for synchronous acquisition; the host computer communication network port 0207 is used to transmit the collected data to the host computer system and receive the control instructions from the host computer system, using the Modbus communication protocol in the form of RS485 and a full-duplex working mode; the base station unit charging interface 0208 can be connected to the AC power supply to charge the base station unit; the base station unit switch 0209 controls the start and stop of the base station unit; the display screen switch 0210 independently controls the on and off of the display screen; the base station unit power indicator 0211 displays the remaining power of the base station unit in real time. All four LED lights are on to indicate that the remaining power of the base station unit is 100%, and each LED light is off to indicate that the power is reduced by 25%;

[0026] Data preprocessing and decoding algorithms carried by the host computer system. Beneficial effects

[0027] Beneficial effects of the present invention:

[0028] (1) High-quality signal synchronous acquisition in multiple scenarios: The established distributed high-density surface electromyography synchronous acquisition system adopts a wireless distributed modular design combined with a low-noise circuit layout to achieve high signal-to-noise ratio, high channel, high sampling rate, and joint acquisition of electromyography signals from multiple different muscle groups.

[0029] (2) Synchronous acquisition of multimodal data: The front-end acquisition system integrates the acceleration signal and the high-density electromyography acquisition array into one module to complete the synchronous acquisition of motion data and high-density electromyography data. The system also supports synchronous input and output trigger acquisition, and synchronized acquisition with external devices.

[0030] (3) Data visualization: This invention adopts a composite base station design to synchronously integrate multi-channel electromyographic signals and stream them to the host computer via WiFi. In combination with interactive UI data analysis software, it can provide low-latency signal display function.

[0031] (4) Development of signal analysis tools: The present invention designs a signal analysis and processing module, which decodes electromyographic signals through steps such as signal preprocessing, channel screening, blind source separation, and cluster analysis, providing an interpretable tool for neuromuscular analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a schematic diagram of the framework of a distributed wireless high-density surface electromyography synchronous acquisition system;

[0033] Figure 2 is a schematic diagram of a high-density electromyography front-end acquisition control unit;

[0034] Figure 3 is a hardware circuit framework diagram of the signal transmission module of the high-density myoelectric front-end acquisition control unit;

[0035] FIG4 is a schematic diagram of the base station unit structure;

[0036] Figure 5 is an external view of the high-density electromyography front-end acquisition control unit; among them, (a) is the overall configuration diagram of the high-density electromyography front-end acquisition control unit, (b) is the front view of the signal transmission module, and (c) is the rear view of the signal transmission module.

[0037] FIG6 is an external view of the base station unit; wherein (a) is an overall external view of the base station unit, and (b) is a structural view of the functional panel of the base station unit.

[0038] Figure 7 is a schematic diagram of the data preprocessing and decoding algorithm of the distributed wireless high-density surface electromyography synchronous acquisition system; among them, (a) is the principle block diagram of the data preprocessing and display module, and (b) is the principle block diagram of the high-density electromyography decoding algorithm module.

[0039] Figure 1: 0101 high-density EMG acquisition array, including immersion gold contacts, copper wiring and polyimide substrate, 0101-1 high-density EMG acquisition array supporting medical double-sided adhesive foam, 0102 signal transmission module, 0103 reference electrode, 0102-1 high-density EMG acquisition array connector, 0102-2 acquisition control unit integrated circuit board, 0102-3 charging contacts, 0102-4 lithium-ion rechargeable battery, 0102-5 reference electrode interface, 0102-6 signal indicator light; 0200 base station unit, 0201 storage box, 0202 status display screen, 0203 charging compartment signal light, 0204 charging compartment, 0205 synchronization input interface, 0206 synchronization output interface, 0207 host computer communication network port, 0208 base station unit charging interface, 0209 base station unit switch, 0210 display screen switch, 0211 base station unit power indicator light. Modes for Carrying Out the Invention

[0040] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings and technical solutions.

[0041] A distributed wireless high-density surface electromyography synchronous acquisition system is proposed. The signal transmission module in the high-density electromyography front-end acquisition control unit is designed with a miniaturized structure to ensure the comfort of human wear. The base station unit is designed as a box-type structure, integrating the synchronization control module, wireless routing module and charging and discharging module. When the system is not in use, the high-density electromyography front-end acquisition control unit can be stored in it to form an integrated structure. The host computer is a user-side computer program equipped with a signal preprocessing and display module and a high-density electromyography decoding algorithm module. The overall system framework diagram is shown in Figure 1.

[0042] When in use, moisten the reference electrode and fix it to the tendon of the human skeletal muscle, attach the high-density electromyography acquisition array to the belly of the skeletal muscle on the surface of the human body, and then connect the reference electrode, high-density electromyography acquisition array and signal transmission module to complete the installation of the high-density electromyography front-end acquisition control unit.

[0043] After the host computer issues an acquisition command, the base unit interprets it and activates the high-density EMG front-end acquisition control unit. The high-density EMG acquisition array transmits the skin's surface EMG signals to the signal transmission module, where the EMG signal processing chip converts the signals into digital signals with 24-bit resolution. The six-degree-of-freedom accelerometer transmits the acceleration signals to the microprocessor. The microprocessor simultaneously receives the high-density EMG signals and the six-axis acceleration signals, packages the signals within the same time period, and sends them to the base unit. The base unit integrates the signals transmitted by multiple front-end acquisition control units and transmits them to the host computer system in real time via a data cable. The host computer displays the data waveform in real time and, after enabling the data storage function, periodically transfers the data to a file in a specified path.

[0044] To address the system's high-fidelity signal acquisition requirements, a proposed preprocessing scheme for the analog signals input to the high-density EMG acquisition front-end ensures the acquisition quality of high-density EMG and acceleration signals. The high-density EMG acquisition front-end controls the purity of the analog signals by constructing an acquisition method suitable for long-term, stable wear, integrating a power management module, and designing a circuit architecture with analog-to-digital separation.

[0045] (1) Design of high-density electromyography front-end acquisition control unit

[0046] In this embodiment, the appearance of the high-density myoelectric front-end acquisition control unit is shown in FIG5 .

[0047] The high-density myoelectric acquisition array 0101 is made of flexible materials, can fit closely to the skin surface, and can complete the transmission of 64-channel myoelectric voltage signals.

[0048] After the reserved holes of the medical double-sided adhesive foam 0101-1 are filled with conductive paste and adhered to the high-density electromyographic acquisition array 0101 and the skin surface, the high-density electromyographic front-end acquisition control unit can be worn for a long time.

[0049] The signal transmission module 0102 converts the voltage-type electromyographic signal into a digital electromyographic signal in the computer, and uploads the digital electromyographic signal to the base station unit.

[0050] The high-density myoelectric acquisition array connector 0102-1 connects the high-density myoelectric acquisition array 0101 and the signal transmission module 0102, making it easier to wear the high-density myoelectric front-end acquisition control unit.

[0051] The acquisition and control unit integrated circuit board 0102-2 includes an EMG signal processing chip, a six-degree-of-freedom accelerometer, a microprocessor, and a power management module. A four-layer copper-clad design reduces inter-channel signal interference. The EMG signal processing chip amplifies, filters, and performs 24-bit resolution analog-to-digital conversion on 64-channel raw EMG signals. The six-degree-of-freedom accelerometer collects human torso acceleration information, providing accurate and comprehensive data for real-time monitoring and recording of individual posture and movement trajectory. The microprocessor communicates with the base station unit in real time via onboard WiFi, packaging and uploading EMG signals, while also receiving and executing control commands from the base station unit. The power management module integrates a low-voltage dropout linear voltage regulator circuit with rectification function. By adjusting the linear output of the P-MOS tube, it ensures the stability of the power supply voltage and minimizes power frequency interference from the power supply.

[0052] The lithium-ion rechargeable battery 0102-4 provides power for the high-density myoelectric front-end acquisition control unit, ensuring that the acquisition equipment can operate continuously for more than four hours or in standby mode for more than ten hours.

[0053] The reference electrode interface 0102-5 uses a hot-swappable terminal block to fix the reference electrode lead, and the other end of the lead is connected to the electromyographic wristband. The electromyographic wristband relies on being soaked in water containing impurities to conduct electricity. A soft, breathable, and highly absorbent fabric strap is selected to ensure wearing comfort and electrode conductivity. The multi-button design on the wristband ensures that multiple reference electrode leads can be connected to the same wristband.

[0054] The signal indicator light 0102-6 can display the operating status of the signal transmission module. The red light flashes when the device is charging, the green light is always on when the device is on standby, and the green light flashes when the device is working.

[0055] (2) Base station unit design

[0056] In this embodiment, the appearance of the base station unit 0200 is shown in FIG6 .

[0057] Storage box 0201 can hold data cables and a high-density electromyography acquisition array. Display screen 0202 can display device status information such as the operating status of each signal transmission module, power usage, signal connection strength, and the remaining power of the base station unit. Charging compartment indicator light 0203 can also indicate the power status of the signal transmission module.

[0058] The charging compartment 0204 is used for charging and storing the signal transmission module. The magnetic design inside the compartment can fix the module to ensure smooth charging of the device.

[0059] The synchronous input interface 0205 is connected to an external device via a BNC q9 connector to perform synchronous acquisition in conjunction with the peripheral device.

[0060] The synchronous output interface 0206 is connected to a peripheral device to control the peripheral device to perform synchronous acquisition.

[0061] The host computer communication network port 0207 is used to transmit collected data to the host computer system and receive control instructions from the host computer system. It adopts the Modbus communication protocol in the form of RS485 and a full-duplex working mode to ensure the flexibility of data exchange.

[0062] The base station unit charging interface 0208 can be connected to an AC power source to charge the base station unit; the base station unit switch 0209 controls the start and stop of the base station unit; the display screen switch 0210 independently controls the lighting of the display screen; the base station unit power indicator light 0211 displays the remaining power of the base station unit in real time. All four LED lights are on, indicating that the remaining power of the base station unit is 100%, and each LED light is off, indicating that the power is reduced by 25%.

[0063] The base station unit supports simultaneous data transmission with 10 high-density front-end acquisition control units. Each high-density front-end acquisition control unit can collect up to 64 channels of electromyographic signals and 6 channels of acceleration signals. That is, the base station unit can simultaneously transmit 640 channels of electromyographic signals and 60 channels of acceleration signals. It also supports device control communication between the upper and lower computers, and can meet the peak transmission bandwidth requirement of 300KSps.

[0064] (3) Upper computer system software function design

[0065] In this embodiment, the data preprocessing and decoding algorithm carried by the host computer is shown in FIG7 .

[0066] Data processed by the signal transmission module is transmitted to the host computer via a network cable in real time. The system software displays the acquired data in real time and stores the collected data in a designated folder. The algorithm module included in the system software can then perform subsequent signal processing and present the analysis results in a graphical user interface.

[0067] In the present invention, the system workflow is as follows:

[0068] After launching the system software, follow the software prompts to locate the base station port. Remove the signal transmission module from the base station unit and connect it to the high-density EMG acquisition array and reference electrode. Once the connection is secure, EMG data can be collected. Before officially storing data, open the waveform window and adjust the device by observing the matching of the collected EMG signal waveform with the movement. Start recording data when the waveform shows fluctuations that follow the movement and a low amplitude in the resting state.

[0069] Users can manage and replay saved files through the host computer system software.

[0070] (1) Data preprocessing and display module

[0071] The raw EMG signals collected by the high-density EMG front-end acquisition control unit contain many noise components, such as motion artifacts, system background noise, and human electrocardiogram (ECG). This noise is primarily concentrated in the low-frequency band, and the filtering module can eliminate most of this noise interference. The filtering module performs anti-aliasing filtering at a sampling frequency of 2000Hz, followed by a 20Hz high-pass second-order Butterworth filter and a 500Hz low-pass second-order Butterworth filter, retaining the EMG signals in the target frequency band of 20-500Hz.

[0072] Improperly wearing the high-density EMG front-end acquisition control unit can seriously affect signal quality. Failure to adhere the high-density EMG acquisition array to the skin or loose reference electrodes can cause EMG signal distortion in some channels. This can manifest as waveform distortion, amplitude exceeding the measurement range, and frequency mismatch between the signal and the target frequency. By setting quality control thresholds, damaged channels are marked, prompting the operator to re-wear the device and providing signal quality evaluation metrics for subsequent EMG analysis.

[0073] (2) High-density electromyography decoding algorithm module

[0074] The preprocessed EMG signals can be subjected to high-density EMG decomposition, and the main components of the multi-channel EMG signals can be decomposed using the FastICA method.

[0075] a. Signal expansion:

[0076] The selected length data is centered and whitened, and after the channel average is subtracted from the data point, the eigenvalue decomposition of the covariance matrix is ​​performed to project the signal into a new coordinate system composed of eigenvectors, eliminating the correlation between the signals and making the signals independent of each other.

[0077] b. Establish constraints and solve the unmixing matrix that maximizes the non-Gaussianity of the source signal:

[0078] An appropriate metric is selected to measure the non-Gaussianity of the signal and an optimization problem is constructed to maximize the non-Gaussianity as the objective and solve the mixing matrix under constraints.

[0079] c. Use the mixed matrix to solve the running unit action potential:

[0080] The resulting mixing matrix is ​​used to restore the mixed signal to its source signal. The restored source signal undergoes further filtering and correlation checking to extract the characteristics of the motor unit action potential. A clustering algorithm is then introduced to combine and classify the separated signals.

[0081] The algorithm outputs the motor unit time series and firing rate information of high-density electromyographic signals, which can be saved to a file for export.

Claims

1. A distributed wireless high-density surface electromyography synchronous acquisition system, characterized in that: The distributed wireless high-density surface electromyography synchronous acquisition system includes a high-density electromyography front-end acquisition control unit, a base station unit, and a host computer. The high-density electromyography front-end acquisition control unit and the base station unit transmit data through a wireless system. The high-density electromyography front-end acquisition control unit includes a high-density electromyography acquisition array, a reference electrode, and a signal transmission module. The base station unit includes a synchronization control module, a wireless routing module, and a charging and discharging module. The host computer is a user-side computer program, which is loaded with a signal preprocessing and display module and a high-density electromyography decoding algorithm module. The client collects and analyzes the information received from the base station unit and displays the results. During use, the reference electrode is moistened and fixed to the tendon of the human skeletal muscle, the high-density electromyography acquisition array is attached to the belly of the human skeletal muscle, and then the reference electrode and the high-density electromyography acquisition array are respectively connected to the signal transmission module; after the host computer issues an acquisition instruction, the base station unit parses the instruction and controls the high-density electromyography front-end acquisition control unit to start working; wherein, the high-density electromyography acquisition array transmits the electromyography signal of the skin surface to the signal transmission module, and the signal transmission module packages the signals within the same time period and sends them to the base station unit, and the base station unit integrates the signals transmitted by multiple high-density electromyography front-end acquisition control units, and transmits the signals to the host computer in real time via the data line; The host computer displays and stores files.

2. The distributed wireless high-density surface electromyography synchronous acquisition system according to claim 1 is characterized in that: The high-density myoelectric acquisition array is composed of immersion gold contacts, copper wiring, and a polyimide substrate. The immersion gold contacts are located on the polyimide substrate and are led out through the copper wiring. The high-density myoelectric acquisition array is distributed and fixed to the belly of each skeletal muscle of the human body through double-sided adhesive foam. The number of contacts on the same high-density myoelectric acquisition array does not exceed 64. The immersion gold contacts on the high-density electromyography acquisition array are arranged according to the shape of the muscle while ensuring consistent spacing.

3. The distributed wireless high-density surface electromyography synchronous acquisition system according to claim 1 is characterized in that: The reference electrode is fixed at the tendons of various skeletal muscles of the human body and adopts a wristband design; multiple high-density myoelectric front-end acquisition control units share one reference electrode.

4. The distributed wireless high-density surface electromyography synchronous acquisition system according to claim 1, characterized in that: The signal transmission module includes a high-density electromyography acquisition array connector, an electromyography signal processing chip, a microprocessor, a six-axis acceleration sensor, a power control module and a battery module; the high-density electromyography acquisition array connector is connected to the high-density electromyography acquisition array to transmit the original electromyography signal to the signal transmission module; the electromyography signal processing chip is used to amplify and sample the electromyography signal, perform bandpass filtering and analog-to-digital conversion; the microprocessor adopts the CC3235S chip with an integrated dual-band Wi-Fi low-power 5G communication chip to perform multi-channel data integration and real-time control of synchronous signal transmission of the received high-density electromyography signal and acceleration signal, ultimately realizing lossless data processing and low-power data communication; the six-axis acceleration sensor integrates a three-axis acceleration sensor and a three-axis gyroscope to realize the acquisition of motion data during the process of human electromyography data acquisition; the power control module and the battery module power the high-density electromyography front-end acquisition control unit and protect the high-density electromyography front-end acquisition control unit from the influence of insufficient or overloaded power load, and adopts a low-voltage difference linear voltage regulator circuit design to reduce the background noise in the collected electromyography signal; Among them, the high-density electromyography acquisition array transmits the skin surface electromyography signal to the signal transmission module, and the electromyography signal processing chip converts the signal into a digital signal with 24-bit resolution; the six-axis acceleration sensor transmits the acceleration signal to the microprocessor, which simultaneously receives the high-density electromyography signal and the acceleration signal, and packages the signals within the same time period and sends them to the base station unit.

5. The distributed wireless high-density surface electromyography synchronous acquisition system according to claim 1 is characterized in that: The synchronization control module sends out timing pulses in the form of broadcasting to notify all high-density electromyography front-end acquisition control units to perform synchronization calibration; the synchronization control module has a synchronization input port and a synchronization output port, wherein the synchronization input port starts the wireless high-density surface electromyography synchronization acquisition system based on the signal input of the external device to complete the synchronization acquisition with the external device; when the host computer issues a start acquisition command, the synchronization control module will synchronously output a pulse to start the external device through the synchronization output port.

6. The distributed wireless high-density surface electromyography synchronous acquisition system according to claim 1, characterized in that: The wireless routing module is used to receive wireless signals transmitted by the high-density electromyography front-end acquisition control unit and send wireless control signals to the high-density electromyography front-end acquisition control unit; after obtaining the electromyography signal, the wireless routing module transmits it to the host computer through a wired network.

7. The distributed wireless high-density surface electromyography synchronous acquisition system according to claim 1, characterized in that: The charging and discharging module includes a power control module and a lithium-ion battery, which is mainly used for charging the high-density electromyography front-end acquisition control unit; the power control module mainly plays the role of voltage reduction and current stabilization, and the lithium-ion battery is used to store electrical energy, providing energy guarantee for the system when an external power supply is unavailable.

8. The distributed wireless high-density surface electromyography synchronous acquisition system according to claim 1, characterized in that: The host computer system is a computer program with integrated storage, computing, and display functions, including a signal preprocessing and display module and a high-density electromyography decoding algorithm module. The signal preprocessing and display module implements spectrum analysis and display of high-density data, high- and low-pass filtering, motion artifact elimination, bad track detection, and damaged data removal, and transmits the data to the high-density electromyography decoding algorithm module. The high-density electromyography decoding algorithm module decomposes the preprocessed high-density electromyography signal based on a blind source separation algorithm to extract the activation and discharge time series of the motor neurons that control the corresponding movement.

9. A distributed wireless high-density surface electromyography synchronous acquisition device, characterized in that: The high-density myoelectric front-end acquisition control unit includes a high-density myoelectric acquisition array (0101), a signal transmission module (0102) and a reference electrode (0103); the high-density myoelectric acquisition array (0101) is connected to the signal transmission module (0102) via a high-density myoelectric acquisition array connector (0102-1), and a high-density myoelectric acquisition array supporting medical double-sided adhesive foam (0101-1) is provided at the bottom of the high-density myoelectric acquisition array (0101); The signal transmission module (0102) includes a high-density myoelectric acquisition array connector (0102-1), an acquisition control unit integrated circuit board (0102-2), charging contacts (0102-3), a lithium-ion rechargeable battery (0102-4), a reference electrode interface (0102-5) and a signal indicator light (0102-6); the circuit portion of the acquisition control unit integrated circuit board (0102-2) includes an electromyographic signal processing chip, a six-axis acceleration sensor, a microprocessor, and a power management module, and is designed with four-layer copper plating; The base station unit (0200) includes a storage box (0201), a display screen (0202), a charging compartment signal light (0203), a charging compartment (0204), a synchronization input interface (0205), a synchronization output interface (0206), a host computer communication network port (0207), a base station unit charging interface (0208), a base station unit switch (0209), a display screen switch (0210), and a base station unit power indicator light (0211); the storage box (0201) is used to place data cables and a high-density electromyography acquisition array; the display screen (0202) is used to display the operating status information, power usage, signal connection strength, and remaining power of each signal transmission module; the charging compartment signal light (0203) is used to display the power status of the signal transmission module; the charging compartment (0204) is used to charge and store the signal transmission module, and the magnetic design inside the compartment can fix the module to ensure stable charging of the device; the synchronization input interface (0205) is connected via BNC The Q9 connector is connected to the external device and cooperates with the peripheral device for synchronous acquisition; the synchronous output interface (0206) is connected to the peripheral device to control the peripheral device for synchronous acquisition; the host computer communication network port (0207) is used to transmit the acquired data to the host computer system and receive the control instructions from the host computer system, using the RS485 Modbus communication protocol and full-duplex working mode; the base station unit charging interface (0208) can be connected to the AC power supply to charge the base station unit; the base station unit switch (0209) controls the start and stop of the base station unit; the display screen switch (0210) independently controls the brightness of the display screen; The base station unit power indicator (0211) displays the remaining power of the base station unit in real time. All four LED lights are on, indicating that the remaining power of the base station unit is 100%. Each LED light is off, indicating that the power is reduced by 25%. Data preprocessing and decoding algorithms carried by the host computer system.

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