Manufacturing method of multi-channel movable electrode

Abstract

The invention belongs to the field of electrode manufacturing, and discloses a manufacturing method of a multi-channel movable electrode, which comprises the following steps: assembling an electrode bracket, respectively forming three holes in the bracket and a slip sheet, and cutting dispensing needles with different specifications as a fixed tube, an inner sleeve (driving tube) and an outer sleeve according to the sizes of the holes; inserting and fixing electrode wires, cutting 16 nickel-chrome alloy coated electrode wires, sequentially inserting the cut nickel-chrome alloy coated electrode wires into an inner sleeve, and fixing the electrode wires on a PCB (Printed Circuit Board) by using a No.2 insect needle; the electrode is coated, the ground wire is welded on the PCB, the ground wire, the insect needle and the electrode wire are sealed and fixed by AB glue, and the protective shell is fixed in front of the electrode support.

Description

Technical Field

[0001] The present invention belongs to but is not limited to the technical field of electrode manufacturing, and in particular relates to a method for manufacturing a multi-channel movable electrode. Background Art

[0002] Human activity is accompanied by a variety of physiological processes, including electrophysiology and blood oxygen metabolism. In situ dual-modal monitoring of electrophysiology and blood oxygen levels is of great significance in fields such as human-machine interfaces, disease diagnosis, and rehabilitation. For example, in medical diagnosis, simultaneous monitoring of electromyographic signals and blood oxygen levels provides a more comprehensive understanding of muscle-vascular activity, providing more precise tools for early diagnosis, rehabilitation assessment, and health management of neuromuscular diseases. Skin is soft and stretchable. To achieve mechanical alignment between electrodes and skin and stable physiological signal monitoring during movement, electrodes must possess properties such as softness, stretchability, and wet adhesion. Furthermore, to achieve information mapping, multi-channel electrodes are essential for more precise acquisition and localization of physiological signals from different locations. Traditional electrodes for physiological signal monitoring have several shortcomings. For example, transparent and stretchable electrodes developed based on conductive materials such as carbon, metal, and PEDOT are generally not inherently transparent, requiring complex structural design to balance transparency and conductivity. Furthermore, to reduce interfacial impedance, the detection pad often needs to be modified with a second layer of hydrogel. In addition, when traditional ultrasound equipment and electromyography equipment are used alone, there are problems such as incomplete information and bulky equipment that is not suitable for long-term monitoring.

[0003] Industrial production processes require precise detection and real-time monitoring of various physical and chemical parameters. These include monitoring parameters such as pH, dissolved oxygen, and redox potential in the chemical, food, and beverage industries, and static electricity levels in electrostatically sensitive industries like electronics manufacturing. Multi-channel movable electrodes enable simultaneous measurement of multiple parameters or locations, improving detection efficiency and accuracy, and providing more comprehensive data support for production process optimization and quality control. For example, in battery production, precise control of electrode preparation and performance is crucial for improving battery charge and discharge efficiency, cycle life, and safety. Multi-channel movable electrodes can be used to monitor and evaluate electrode material properties in real time, helping to optimize production processes and improve product quality and efficiency. Industrial environments are often complex, characterized by high temperatures, high pressures, and corrosive media. Traditional fixed electrodes may not meet the long-term stability requirements of these complex environments. Multi-channel movable electrodes offer greater flexibility and adaptability, allowing for adjustment and replacement based on actual measurement needs to ensure accurate and reliable measurements.

[0004] The closest existing technology involves a multi-channel microelectrode array device and its implantation method. This device utilizes a rigid silicon substrate to integrate multiple electrode channels, achieving a certain channel density and a preliminary miniaturized structure. It is primarily intended for applications in neural signal recording and stimulation. However, this technology utilizes a monolithic, non-adjustable positioning structure, with each electrode channel fixed to a single rigid substrate. This lacks the independent displacement capability of individual channels, making it difficult to adapt to the spatial adjustments required for dynamically targeting neural regions. Furthermore, it suffers from high mechanical rigidity, poor biocompatibility, and the potential for tissue rejection after long-term use.

[0005] This existing technology faces challenges in practical industrial applications, including low assembly precision, complex packaging, and weak anti-interference capabilities of the conductive paths. This is particularly true in high-channel deployment scenarios, where crosstalk and heat buildup can easily occur, impacting signal quality and device lifespan. Furthermore, existing rigid structure electrodes typically rely on MEMS processes for high-precision machining, resulting in high manufacturing costs and complex maintenance. This hinders low-cost, large-scale replication and clinical application, limiting their potential for engineering applications in personalized neural interface systems. Summary of the Invention

[0006] In view of the problems existing in the prior art, the present invention provides a method for manufacturing a multi-channel movable electrode.

[0007] The present invention is achieved by providing a method for manufacturing a multi-channel movable electrode, characterized in that the electrode is multi-channel and movable, and the method specifically comprises:

[0008] S1: Assembly of the electrode holder. Both the holder and the slide have three holes. Dispensing needles of different specifications are cut according to the size of the holes to serve as the fixed tube, inner sleeve (driving tube) and outer sleeve.

[0009] S2: Insert and fix the electrode wire. Cut 16 nickel-alloy coated electrode wires and insert them into the inner sleeve in sequence. Then use a No. 2 insect needle to fix the electrode wires on the PCB.

[0010] S3: Electrode wrapping, soldering the ground wire on the PCB board, sealing and fixing the ground wire, insect pin and electrode wire with AB glue, and fixing the protective shell in front of the electrode holder.

[0011] Furthermore, the step S1 includes:

[0012] (1) Insert an M1×7 screw into the middle hole of the slide, secure the slide and screw with a hexagonal M1 nut, and secure the nut to the slide with AB glue. Then insert the inner sleeve into the hole on the right side of the slide and secure it.

[0013] (2) Fix the outer sleeve, M1 nut and outer sleeve through the corresponding holes of the bracket;

[0014] (3) Insert the fixing tube into the left hole of the slide, screw into the nut on the bracket, insert the inner sleeve on the slide into the outer sleeve, and connect the slide and the bracket together;

[0015] (4) Solder the PCB board and the adapter together and use a multimeter to test the connection. The adapter has a double row of round pins with a spacing of 1.27mm.

[0016] (5) Use AB glue to fix the PCB board on the bracket.

[0017] Furthermore, in S2, each electrode wire needs to be cut into 7-8 cm, 16 electrode wires are inserted into the inner sleeve in sequence, and then each electrode wire is fixed to the PCB board with a No. 2 insect needle. The resistance value of each electrode wire is controlled at 0.1-0.2 MΩ.

[0018] Furthermore, the S3, ground wire diameter 0.2mm silver wire, fixes the protective shell on the front of the electrode holder, and the front of the electrode holder is exposed.

[0019] In combination with the above technical solutions and the technical problems solved, the advantages and positive effects of the technical solutions to be protected by the present invention are as follows:

[0020] First, this invention focuses on the core requirements of high channel density, controllable scalability, and microstructure integration in cutting-edge applications such as neuromodulation, electrophysiological recording, and deep brain stimulation. To address the limited number of channels, non-adjustable structure, and poor long-term implant stability of traditional rigid electrode assemblies, a three-layer, nested catheter microstructure assembly solution is proposed. This structure achieves high-precision linear actuation of the microelectrode's spatial position through axial linkage between the slide and the bracket, fundamentally resolving the technical difficulties of existing rigid electrodes in balancing multi-channel and dynamic positioning, and improving the spatial docking accuracy of target neural clusters.

[0021] In terms of microstructure manufacturing, this invention introduces a combination of a polyimide-embedded tube array, a nickel-coated alloy-coated electrode wire, and multi-needle crimping welding, overcoming the high barrier to entry for existing multi-channel electrode assembly, which relies on microelectromechanical machining (MEMS) equipment. This industrial transformation path, achieved through conventional experimental-grade processing techniques, achieves both functional density and structural modularity. This significantly improves the process universality and mass production feasibility of electrode assemblies, providing a more flexible process implementation paradigm for the electrode preparation industry.

[0022] This invention utilizes an AB glue overall packaging strategy and a ring-grounded coplanar wiring design to achieve coordinated shielding of the structure and electrical signal paths. This effectively suppresses high-frequency interference conduction paths at the electrode interface, reducing the risk of contact impedance drift and signal distortion during insertion and removal. Compared to conventional methods using surface coatings or external shielding covers, this solution offers significant advantages in signal fidelity and interface reliability, providing a more stable underlying channel for complex EEG and evoked potential signal acquisition.

[0023] From a system integration perspective, this approach enables rapid docking and flexible deployment between cross-platform neural modules (such as head-mounted brain-computer interfaces and animal experiment platforms) through structural reusability, standard electrode interfaces, and electro-optical composite channel integration. Its modular design philosophy and highly scalable interface specifications establish a standardized manufacturing logic for future wearable neural electrode devices, providing a foundation of highly compatible and cost-effective core components for mid- and downstream terminal equipment manufacturers in the industry chain. It is expected to gain widespread deployment and licensing protection value in the fields of brain science research, chronic neurological disease treatment, and closed-loop neurofeedback devices.

[0024] Second, from a medical perspective, in neuroscience research and brain-computer interface applications, multi-channel movable electrodes can accurately collect neural signals, providing critical data support for the diagnosis and treatment of neurological diseases. For example, brain-computer interfaces (BCIs) have the potential to help patients with ALS, high-level paraplegia, and other conditions regain the ability to communicate with the outside world and control external devices. Furthermore, as the technology matures and products evolve, their application in rehabilitation therapy equipment will gradually expand, further increasing revenue streams.

[0025] In the scientific research field, multi-channel movable electrodes can be widely used in research in areas such as brain science and psychology. Demand for multi-channel movable electrodes from scientific research institutions will continue to grow. Strengthening cooperation with them will not only secure stable order revenue but also promote further technological optimization through scientific research projects, forming a virtuous cycle, enhancing product market competitiveness, and ultimately achieving higher commercial value.

[0026] The core advantages of this invention, the "multi-channel movable electrode," lie in its mobility and multi-channel nature, and are key to filling a gap in the industry. In EEG signal acquisition research, it can simultaneously monitor the activity of multiple brain regions, providing massive and accurate data support for in-depth exploration of the brain's neural activity mechanisms, contributing to a better understanding of the brain's network activity and information processing mechanisms. Dynamic monitoring can be performed in different brain regions based on actual needs, transmitting electrical signals to a computer terminal for visual presentation. Through the combination of multiple electrode positions and intelligent analysis algorithms, it can accurately determine the source location of the signal, effectively improving the spatial resolution of EEG signals or other monitoring signals.

[0027] The present invention's sophisticated and innovative architecture integrates multiple electrode channels onto a flexible, removable carrier. Not only is its compact size precise enough to conform to human skin or sample surfaces, minimizing signal interference, but it also features independent signal acquisition capabilities, enabling simultaneous multi-channel signal acquisition. Compared to traditional electrodes, this significantly increases the number of channels available for signal acquisition, enabling comprehensive and detailed acquisition of electrophysiological signals.

[0028] In addition, the present invention is simple to manufacture, low in cost, and has a wide range of applications, while some high-end electrode products from abroad are expensive, which limits their widespread application. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a flow chart of a method for manufacturing a multi-channel movable electrode provided by an embodiment of the present invention;

[0030] Figure 2 Schematic diagram of a multi-channel movable electrode provided by an embodiment of the present invention.

[0031] Figure 3 Schematic diagram of a bracket provided in an embodiment of the present invention.

[0032] Figure 4 Schematic diagram of a slide provided by an embodiment of the present invention.

[0033] Figure 5 Schematic diagram of a PCB board provided by an embodiment of the present invention.

[0034] Figure 6 3 is a correlation diagram between the PMv brain region and sleep-wakefulness provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0036] like Figure 1 As shown, an embodiment of the present invention provides a method for manufacturing a multi-channel movable electrode, the method specifically comprising:

[0037] S1: Assembly of the electrode holder. Both the holder and the slide have three holes. Dispensing needles of different specifications are cut according to the size of the holes to serve as the fixed tube, inner sleeve (driving tube) and outer sleeve.

[0038] S2: Insert and fix the electrode wire. Cut 16 nickel-alloy coated electrode wires and insert them into the inner sleeve in sequence. Then use a No. 2 insect needle to fix the electrode wires on the PCB.

[0039] S3: Electrode wrapping, soldering the ground wire on the PCB board, sealing and fixing the ground wire, insect pin and electrode wire with AB glue, and fixing the protective shell in front of the electrode holder.

[0040] This invention achieves a slidable positioning structure for the microelectrode assembly by sequentially nesting a three-layer catheter (fixed tube, inner sleeve, and outer sleeve) within the electrode holder. The fixed tube provides initial positioning and structural support, while the inner sleeve (driving tube) achieves longitudinal displacement via an external drive mechanism, thereby precisely driving the electrode wire forward and backward. The outer sleeve acts as a guiding protective layer, reducing friction and deformation of the electrode wire during advancement and ensuring a stable conductive path.

[0041] The electrode wire is coated with a nickel-chrome alloy, a material with excellent electrical conductivity and corrosion resistance, suitable for long-term, stable signal acquisition. Its insertion process relies on the axial flexibility of the microcatheter, combined with the matching constraints of the inner and outer sleeves, to effectively avoid unstable electrode wire forms such as "mechanical rebound" or "end warping" during assembly, thereby improving consistency and spatial distribution accuracy across multiple channels.

[0042] The No. 2 Insect Needle's point-like crimping between the electrode wire and the PCB pad creates a low-impedance, mechanically fatigue-resistant electrical connection. This connection method not only enhances the initial mechanical retention of the electrode wire but also improves the system's connection reliability under repeated plugging and unplugging or dynamic displacement conditions, meeting the durability requirements of removable electrode assemblies in long-term use scenarios.

[0043] The PCB grounding system utilizes a coplanar ground wire layout. The ground wire, exposed electrode wire segments, and fixed pins are encapsulated with AB adhesive, effectively isolating the signal acquisition quality from external electromagnetic interference (EMI) and mechanical vibration. AB adhesive exhibits excellent dielectric properties and thermal stability, protecting the electrode interface while also enhancing the overall structural strength of the device.

[0044] The rigid docking design of the front protective shell and the bracket not only provides travel limit for the forward-moving electrode wire, but also prevents external impact forces from being transmitted to the core area of ​​the electrode wire. This structure optimizes the mechanical response of the multi-channel electrode during puncture, insertion, or repositioning, reducing unintended displacement and improving the steady-state compatibility of the biological tissue interface.

[0045] In summary, the multi-channel movable electrode system provided by the present invention realizes a precise control model of "hierarchical drive-rigid-flexible coordination" in its structural layout. Combining the high-performance characteristics of nickel-chrome alloy-coated electrode materials with a multi-dimensional packaging protection strategy, the entire electrode system has a high degree of integration, reconfigurability and long-term reliability in application scenarios such as minimally invasive physiological monitoring, neural interface recording or deep brain stimulation.

[0046] The step S1 includes:

[0047] (1) Insert an M1×7 screw into the middle hole of the slide, secure the slide and screw with a hexagonal M1 nut, and secure the nut to the slide with AB glue. Then insert the inner sleeve into the hole on the right side of the slide and secure it.

[0048] (2) Fix the outer sleeve, M1 nut and outer sleeve through the corresponding holes of the bracket;

[0049] (3) Insert the fixing tube into the left hole of the slide, screw into the nut on the bracket, insert the inner sleeve on the slide into the outer sleeve, and connect the slide and the bracket together;

[0050] (4) Solder the PCB board and the adapter together and use a multimeter to test the connection. The adapter has a double row of round pins with a spacing of 1.27mm.

[0051] (5) Use AB glue to fix the PCB board on the bracket.

[0052] In the S2, each electrode wire of the photoelectrode needs to be cut into 7-8 cm, and 16 electrode wires are inserted into the inner sleeve in sequence. Then, the electrode wires are fixed to the PCB board with a No. 2 insect needle. The resistance value of each electrode wire is controlled at 0.1-0.2 MΩ.

[0053] The S3 ground wire is a silver wire with a diameter of 0.2 mm, which fixes the protective shell to the front of the electrode holder, and the front of the electrode holder is exposed.

[0054] The schematic diagram of the multi-channel movable electrode provided by the embodiment of the present invention is as follows Figure 2 shown.

[0055] The schematic diagram of the bracket provided in the embodiment of the present invention is as follows Figure 3 shown.

[0056] The schematic diagram of the slide provided by the embodiment of the present invention is as follows Figure 4 shown.

[0057] The schematic diagram of the PCB board provided by the embodiment of the present invention is as follows Figure 5 shown.

[0058] Figure 2 The multi-channel movable electrode shown in the figure: This structure assembles multiple independent electrode units using mechanical guides, allowing precise movement in specific directions to achieve multi-point signal acquisition. The electrodes are connected to an external control system, which can independently adjust the contact pressure and depth of each electrode. It is suitable for multi-channel signal acquisition scenarios such as EEG and biopotential. This structural design optimizes spatial layout and improves sampling accuracy and stability.

[0059] Figure 3The bracket structure shown is a closed box with multiple through-holes for securing the electrode assembly and screw holes for connecting the side, facilitating stable installation and removal of the electrode module. Made of lightweight, high-strength materials and featuring an optional insulating coating, the bracket provides structural support in precision electronics experiments, preventing electromagnetic interference and loosening.

[0060] Figure 4 The slide structure shown is a rectangular block with holes of varying diameters in the center for guiding electrode pins and cable harnesses. The slide slides within the guide grooves, and its position is precisely controlled by a stopper. This makes it ideal for positioning electrodes or organizing cable harnesses during experiments, enhancing flexibility and repeatability.

[0061] Figure 5 The PCB shown integrates electrode signal access ports and a signal conditioning module. Each channel features independent filtering and amplification circuitry to ensure signal integrity. A standard pin header is located on one side of the PCB, facilitating connection to a host computer or data acquisition module. The overall layout is compact and highly resistant to interference, making it suitable for multi-channel, high-precision electrical signal acquisition.

[0062] like Figure 6 Our research group used in vivo multi-channel and simultaneous EEG / EMG recording methods to confirm the correlation between the PMv brain region and sleep-wakefulness (Figures A and B). In vivo multi-channel recording involves implanting the removable multi-channel electrode of this invention into the PMv brain region to record neurons related to sleep-wakefulness. The PMv brain region is approximately 5.34-5.66mm below the cortex. By rotating the "M1" slotted screw 90°, the electrode depth decreases by 62.5μm, allowing five recordings per mouse, greatly increasing the number of recorded neurons. The recorded neurons were retained and isolated using MATLAB 2014b and the offline cluster analysis software MClust-4.4. As shown in Figure C, the neurons recorded by this electrode have a high signal-to-noise ratio, and neurons are easy to separate, with the following advantages: ① "ISI < 2ms" < 1%: the noise ratio of the neuronal discharge time interval (inter-spike-interval) is < 1%, indicating that the recorded neurons are less interfered with by other electrical signals; ② ID > 20: the Mahalanobis distance (isolation distance) that separates neurons from noise. The larger the value, the farther the neuron is from other signals and the easier it is to distinguish; ③ LR < 0.1: the ratio of noise in the neuronal firing cluster. The smaller the value, the easier it is to separate the recorded electrical signals.

[0063] The above description is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with this technical field within the technical scope disclosed by the present invention and within the spirit and principles of the present invention should be covered by the scope of protection of the present invention.

Claims

1. A method for manufacturing a multi-channel movable electrode, characterized in that: The following steps are involved: S1: Assemble the electrode holder and fit the holder to the slide. The holder and the slide are each provided with three sets of through holes, which are used to insert a fixed tube, an inner sleeve, and an outer sleeve, respectively. The three tubes are nested to form a slidable guide structure. S2: Inserting and fixing the electrode wires. Insert several nickel-chrome alloy-coated electrode wires into the inner sleeve in sequence and fix the electrode wires to the circuit connection board through the connecting structure. S3: Electrode wire wrapping and packaging: weld the ground wire on the circuit connection board, and use insulating colloid material to package the ground wire, electrode wire and connection structure as a whole, and fix the front protective shell to the front end of the electrode bracket.

2. The method according to claim 1, wherein The fixed tube, inner sleeve and outer sleeve are nested in sequence to form a sliding structure. The inner sleeve can move axially within the outer sleeve to drive the electrode wire to achieve controllable expansion and contraction.

3. The method according to claim 1, wherein the electrode wire is a nickel-chrome alloy conductor, the surface of which is coated with a corrosion-resistant electrical insulation coating, the length of a single wire is 7 to 8 cm, and the resistance value is controlled between 0.1 and 0.2 megohms.

4. The method according to claim 1, wherein The slide and the bracket are detachably connected by screws and nuts. The middle hole of the slide is used to install the screws, the left hole is inserted into the fixing tube, and the right hole is inserted into the inner sleeve. The outer sleeve is plugged into the corresponding holes of the bracket to achieve structural docking and guidance.

5. The method according to claim 1, wherein The electrode wire and the circuit connection board are electrically connected by fine needle crimping. The fine needle is a medical No. 2 insect needle, and point crimping is used to enhance electrical conduction stability and mechanical fixation performance.

6. The method according to claim 1, wherein The circuit connection board is connected to the adapter by welding. The adapter is a double-row circular pin connector with a spacing of 1.27 mm. After welding is completed, it must pass the conduction test before it can be packaged.

7. The method according to claim 1, wherein The ground wire is made of silver wire with a diameter of 0.2 mm. The ground wire, exposed section of electrode wire and fixed needle on the circuit connection board are encapsulated with epoxy glue to form an electromagnetic shielding layer and a structural protection layer.

8. The method according to claim 1, wherein The front end protective shell is rigidly connected to the electrode bracket through an adhesive to form a limiting device for the extension path of the electrode wire, and the front end of the protective shell is open to keep the electrode wire exposed.

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