Non-invasive neuromodulation intervention device and wearable electrode therefor

Abstract

The patent relates to the technical field of biomedical engineering, and particularly to a wearable electrode, which comprises a base assembly, the base assembly comprising a support layer and a buffer layer covering the surface of the support layer, the density of the support layer being greater than that of the buffer layer, and a groove being formed on the buffer layer; a micro-boss, the micro-boss being arranged on the support layer and located in the groove formed by the buffer layer; and an electrode layer, the electrode layer having a main branch and a terminal branch, the main branch being arranged on the top of the micro-boss, and the terminal branch being suspended on the buffer layer; the height of the buffer layer being higher than that of the micro-boss when no pressure is applied; and the buffer layer being able to be compressed when subjected to external pressure, so that the main branch of the electrode layer is exposed and in contact with an object pressing the buffer layer, thereby significantly improving the signal stability and stimulation reliability in a dynamic environment.

Description

Technical Field

[0001] This patent relates to the field of biomedical engineering technology, specifically to a wearable electrode with a multi-level damping buffer structure and an adaptive conduction mechanism, and a non-invasive neuromodulation intervention device containing the electrode. The intervention device is suitable for a closed-loop neuromodulation system based on electroencephalographic feedback, which can employ electrical stimulation technology. Background Technology

[0002] In physiological signal monitoring and electrical stimulation therapy applications, electrodes serve as a crucial interface between the human body and electronic devices, and their contact stability directly determines the signal-to-noise ratio of signal acquisition or the efficiency of energy transmission. Existing technologies include wearable electrode solutions based on flexible substrates. These solutions typically employ a single elastic material or a simple layered structure, fixed to the skin surface by an adhesive or directly attached. Such existing technologies can maintain basic electrical connections in static or low-dynamic environments.

[0003] However, in scenarios involving complex anatomical structures with curved surfaces (such as cranial prominences and mastoid structures) and frequent movements, the aforementioned existing technologies generally exhibit insufficient adaptability. Because existing electrode structures often lack a graded response mechanism for different pressure ranges, the contact pressure between the electrode and skin fluctuates continuously when the wearer moves their head or the external pressure changes. This fluctuation causes a non-linear change in the contact area at the skin-electrode interface, leading to continuous drift rather than stable switching of the interface impedance. In low-power monitoring conditions, minute pressure fluctuations can lead to poor contact and introduce noise; while in conditions requiring high-current stimulation, existing structures struggle to reliably increase the effective contact area to reduce impedance at specific pressure thresholds. Furthermore, existing electrodes made of single materials or with simple composite structures are prone to localized stress concentrations or gaps when facing differences in curvature across different areas of the head, further exacerbating the uncertainty of the contact state in dynamic environments, resulting in signal distortion, uneven stimulation, or decreased wearing comfort. Summary of the Invention

[0004] To solve, or at least partially solve, the above-mentioned technical problems, the present invention provides a wearable electrode, comprising: A base assembly, the base assembly including a support layer and a buffer layer covering the surface of the support layer, the density of the support layer being greater than the density of the buffer layer, and grooves being formed on the buffer layer; Micro-protrusions are disposed on the support layer and located within the groove formed by the buffer layer; An electrode layer having a main branch and terminal branches, wherein the main branch is disposed on the top of the micro-protrusion and the terminal branches are suspended on the buffer layer; When not under pressure, the height of the buffer layer is higher than that of the micro-protrusion; the buffer layer can be compressed under external pressure to expose the main branches of the electrode layer and make contact with the object pressing against the buffer layer.

[0005] By constructing a dual-layer substrate structure with density differences, a high-density support layer provides a rigid framework, while a low-density buffer layer provides a flexible fit, with a limiting reference defined by micro-protrusions between the two. In the uncompressed state, the terminal branches of the electrode layer preferentially contact the object to form a first conductive path; when the external pressure reaches a certain threshold and compresses the buffer layer, the main branches contact the object to form a second conductive path. This structure achieves a step-like switching of contact states rather than nonlinear drift, filters low-frequency motion noise using mechanical limiting, and clearly distinguishes between the default contact state and the compression-enhanced state, thereby significantly improving signal stability and stimulus reliability in dynamic environments.

[0006] Optionally, the micro-protrusion has an elongated shape that matches the length of the main branch, the micro-protrusion is arranged along the extension direction of the main branch, the width of the groove is 0.1 mm to 0.5 mm larger than the width of the micro-protrusion; the spacing between adjacent micro-protrusions is ≥2 mm, and the height of the micro-protrusion is in the range of 0.5 mm to 2.0 mm.

[0007] By limiting the geometry and tolerance range of the micro-protrusions, precise geometric fit between the micro-protrusions and the main branches of the electrodes is ensured, achieving uniform triggering across the entire line. At the same time, the reliability of the triggering action is guaranteed within the manufacturing tolerance range, balancing structural matching accuracy and mass production cost.

[0008] Optionally, the electrode layer has a self-similar topology, which includes multiple recursively generated levels, wherein branches at lower levels constitute the trunk branches and branches at higher levels constitute the terminal branches; the terminal branches are disposed on the surface of the buffer layer for contacting the object to form a first conductive path; the trunk branches are disposed on the top of the micro-protrusions for contacting the object when the buffer layer is compressed to form a second conductive path.

[0009] By leveraging the multi-scale characteristics of fractal geometry, different levels of electrode branches are mapped to different mechanical triggering heights. In the default state, only the distal contacts maintain basic conduction. After compression, the main trunk participates in contact, achieving a step increase in contact area. This realizes a pressure-driven adaptive conduction mechanism, significantly reducing contact impedance fluctuations under dynamic pressure changes and improving signal-to-noise ratio and stimulation uniformity.

[0010] Optionally, the self-similar topology is one of H-tree fractal, Koch snowflake fractal, or Sierpinski triangle fractal; when the self-similar topology adopts H-tree fractal, the branches from Level 1 to Level 2 are the main branches, and the branches from Level 3 to Level 5 are the terminal branches; the linewidth of the electrode layer is halved at each level to adapt to the current density distribution of different levels.

[0011] The hierarchical allocation of the H-tree fractal directly corresponds to the height difference logic triggered by mechanical triggering, achieving a high degree of coupling between structural functions. The design of halving the linewidth at each level matches the current carrying requirements of each branch, reducing overall resistance and material consumption while optimizing conductivity stability, providing a reproducible topology basis for different application scenarios.

[0012] Optionally, the support layer is made of medical-grade silicone or high-density polyurethane foam, and the buffer layer is made of medical-grade memory foam; the density of the support layer is not less than 180 kg / m³, the density of the buffer layer is 30 kg / m³ to 120 kg / m³, and the density difference between the support layer and the buffer layer is ≥100 kg / m³; the thickness of the support layer is 3 mm to 5 mm, and the Shore A hardness is 40 to 60; the thickness of the buffer layer is 3 mm to 10 mm, and the rebound time is 2 seconds to 4 seconds.

[0013] By defining specific material parameters, the material foundation for the multi-level damping buffer system is established. The high density difference ensures asynchronous deformation, and the specific thickness, hardness, and rebound time are matched with the curvature of the head and the frequency of human movement, ensuring that the structure does not undergo plastic collapse during long-term wear, while balancing trigger sensitivity and wearing comfort.

[0014] Optionally, the support layer divides at least two functional regions on the outer surface of the base assembly, and the equivalent density of the support layer located in different functional regions is different; the functional regions divided by the support layer include a central region and an edge region, the equivalent density of the central region is 250 kg / m³ to 500 kg / m³, and the equivalent density of the edge region is 150 kg / m³ to 300 kg / m³.

[0015] By using a regionalized stiffness design, the central area of ​​the electrode provides stable support, while the edge area adapts to the curved surface transition, effectively avoiding local stress concentration, improving the fit of the electrode to complex head contours, ensuring that the triggering mechanism works effectively throughout the entire area, and reducing the feeling of wearing a foreign object.

[0016] Optionally, the support layer achieves equivalent density differences in different functional areas through local openings; the local openings are one of a honeycomb structure, a corrugated structure, or a grid support structure; the opening rate of the local openings is 10% to 60%.

[0017] A low-cost and easy-to-manufacture stiffness adjustment method is provided, which can achieve multi-region stiffness matching without changing materials by using the hole pattern and hole ratio. This simplifies the production process and improves the consistency of the structure, enabling complex stiffness gradient distributions to be achieved with a single material layer.

[0018] Optionally, the aperture ratio of the central region is less than that of the edge region; the aperture ratio of the central region is 10% to 30%, and the aperture ratio of the edge region is 30% to 60%.

[0019] By controlling the opening ratio, the stiffness difference between the central and edge regions was refined, achieving a smooth transition in stiffness and avoiding stress concentration caused by abrupt changes in stiffness. This further improved wearing comfort and the reliability of the triggering mechanism on complex curved surfaces.

[0020] Optionally, the wearable electrode has a trigger pressure threshold. When the external pressure reaches the trigger pressure threshold, the buffer layer is compressed until the main branch contacts the object. The trigger pressure threshold ranges from 3 kPa to 7 kPa. The trigger pressure threshold satisfies a mechanical model: ,in, For correction factor, The trigger pressure threshold, The Young's modulus of the buffer layer. The height difference between the buffer layer and the micro-protrusion. The initial thickness of the buffer layer, The value range is from 0.8 to 1.2.

[0021] This preferred approach transforms empirical triggering mechanisms into calculable and predictable engineering parameters. By introducing a mechanical model and correction coefficients, a quantitative relationship between material properties, geometric dimensions, and triggering pressure is established, guiding product design and parameter selection. This significantly improves the reproducibility of the approach, ensures reliable electrode switching under typical head movement pressure, and prevents performance instability caused by parameter ambiguity.

[0022] Optionally, the substrate assembly further includes a thin-film pressure sensor layer disposed at the bottom of the support layer. The thin-film pressure sensor layer is used to monitor the contact pressure applied to the wearable electrode in real time and coordinate with the signal of the electrode layer to provide feedback on the contact status. The pressure response range of the thin-film pressure sensor layer is 0 kPa to 20 kPa, and the sensitivity resolution is ≤10 Pa. It also includes a flexible conductive path that runs through the support layer and the buffer layer and is used to transmit the electrical signal of the electrode layer to an external device. The flexible conductive path includes microchannels disposed in the support layer and the buffer layer, and conductive material filled in the microchannels. It also includes a transparent conductive hydrogel layer that covers the surface of the electrode layer away from the buffer layer, serving as an interface for direct contact with the object. The thickness of the transparent conductive hydrogel layer is 0.5 mm to 1.5 mm, and it has conductivity and biocompatibility.

[0023] This enables real-time visual monitoring of the contact status and reliable signal transmission. The thin-film pressure sensor layer provides quantitative data independently of the electrode triggering structure, the flexible conductive path ensures connection stability under multi-layer deformation, and the transparent conductive hydrogel layer significantly reduces the contact impedance at the skin-electrode interface due to its high water content and ionic conductivity, while providing a soft touch, improving signal acquisition quality, electrical stimulation uniformity, and the comfort and safety of long-term wear.

[0024] Optionally, the wearable electrode is configured for head EEG monitoring scenarios, adapted to complex curved surfaces such as skull protrusions, mastoid structures, or the temporal region, and the trigger pressure threshold is configured to filter motion artifacts generated by daily head movements; or, the wearable electrode is configured for transcutaneous electrical nerve stimulation scenarios, configured to utilize the first conductive pathway in a low-power monitoring state and the second conductive pathway in a high-current stimulation state.

[0025] In EEG monitoring scenarios, thresholding mechanisms are used to suppress impedance fluctuation noise caused by motion, adapting to complex anatomical structures; in electrical stimulation scenarios, dual-modal power consumption management is achieved, with low power consumption for static monitoring and high reliability for dynamic stimulation.

[0026] The present invention also provides a non-invasive neuromodulation intervention device having wearable electrodes as described in any one of the foregoing.

[0027] This device integrates the aforementioned bistable triggering mechanism, fractal topology design, and multi-level damping buffer structure of wearable electrodes into a complete electrical stimulation system. During transcranial electrical stimulation (TCS) therapy, the device ensures stable contact between the stimulation electrode and the scalp, utilizes mechanical limiting to filter impedance fluctuations caused by movement, maintains a low-power state during static monitoring, and switches to a highly reliable conduction state during dynamic stimulation. This system integration extends protection to the device level, preventing competitors from circumventing the patent protection of the electrode components themselves through overall device integration, while providing stable interface contact for TCS therapy, improving the consistency and safety of treatment effects.

[0028] In summary, this invention constructs a mechanical trigger base using a composite structure of a high-density support layer and a low-density buffer layer. Combined with a self-similar fractal electrode topology design, it forms a complete multi-level damping buffer and adaptive conduction technology system. This system systematically solves the technical problem of continuous impedance fluctuations and difficulty in threshold switching caused by changes in contact pressure during dynamic wearing of existing wearable electrodes. It achieves step switching of impedance response, significantly improving signal stability, stimulation uniformity, and wearing comfort under complex curved surfaces and motion conditions. Attached Figure Description

[0029] To more clearly illustrate the embodiments of this patent, the relevant drawings will be briefly described below. It should be understood that the drawings described below are only for illustrating some embodiments of this patent, and those skilled in the art can obtain many other technical features and connections not mentioned herein based on these drawings.

[0030] Figure 1 This is a schematic diagram of the structure of a wearable electrode according to an embodiment of this patent; Figure 2 This is a schematic diagram of the electrode layer pattern when the wearable electrode of this patent embodiment adopts an H-tree fractal self-similar topological structure; Figure 3 This is a schematic diagram of the structural modules of the wearable electrode in the embodiment of this patent when adopting an H-tree fractal self-similar topology. Figure 4 This is an example diagram showing the dimensions of an electrode layer in the wearable electrode of this patent embodiment when using an H-tree fractal self-similar topology. Figure 5 This is a flowchart illustrating the workflow of the wearable electrode according to the embodiments of this patent in a practical application scenario. Figure 6 This is a schematic diagram of the module of the non-invasive neuromodulation intervention device according to the embodiments of this patent.

[0031] Explanation of reference numerals in the attached figures: 1. Support layer; 11. Micro-protrusions; 2. Buffer layer; 21. Groove; 3. Sensor layer. Detailed Implementation

[0032] Wearable electrodes serve as a crucial interface for bioelectrical signal acquisition and nerve electrical stimulation, and their performance directly determines the signal-to-noise ratio of monitoring data and the stability of treatment effects. In typical head EEG monitoring or transcutaneous electrical nerve stimulation applications, electrodes need to be in contact with the scalp for extended periods. The scalp surface is not an ideal plane but a complex curved surface covered by cranial protrusions, mastoid structures, and hair. Furthermore, the human body inevitably undergoes head movements during daily activities, causing dynamic changes in the contact pressure between the electrodes and the skin.

[0033] In existing technologies, to adapt to the curvature of the head and maintain contact, a cushioning structure made of a single elastic material or reliance on the adhesive force of medical tape for fixation is typically used. For example, common ear-worn or head-worn electrode solutions often use silicone sleeves or memory foam as intermediate cushioning layers, utilizing the elastic recovery of the material to compensate for unevenness in the skin surface. Some solutions further integrate thin-film pressure sensors for real-time monitoring of contact status. These existing solutions improve wearing comfort to some extent and provide basic contact pressure feedback.

[0034] However, in long-term dynamic wear applications, existing solutions based on single elastic materials or simple adhesion have been found to have certain technical limitations. Because the buffer layer material is homogeneous and continuous, its deformation characteristics exhibit a linear or near-linear stress-strain relationship. When external pressure fluctuates due to movement, the contact area between the electrode and the skin continuously shifts, causing the skin-electrode interface impedance to become unstable. This continuous impedance fluctuation manifests as low-frequency motion artifacts in signal monitoring and leads to uneven current density distribution in electrical stimulation, potentially causing localized stinging or stimulation failure. More critically, existing solutions lack a clear contact state switching mechanism, failing to establish a reliable physical boundary between low-power monitoring modes and high-current stimulation modes, making it difficult for the system to automatically adjust operating parameters based on the contact state.

[0035] Intuitively, possible improvements might include simply increasing the stiffness of the cushioning layer to improve support, or simply increasing the sensitivity of the sensor to compensate for impedance fluctuations through algorithms. However, increasing stiffness significantly reduces wearing comfort, especially at bony prominences where pressure points are easily created, and it fails to address the issue of unstable microscopic contact. Relying solely on algorithmic compensation is problematic if the physical contact itself experiences high-frequency vibrations or momentary circuit breaks, leading to a deterioration in signal quality and making it difficult for backend processing to fully recover valid information. Furthermore, simply superimposing a pressure sensor onto traditional electrodes without decoupling the sensing and conductive pathways in the mechanical structure often results in sensor deformation interference coupling into the bioelectrical signal, introducing additional noise.

[0036] In view of this, this embodiment aims to provide a wearable electrode with a composite structure and related devices, in order to solve or at least partially alleviate the above-mentioned technical problems.

[0037] The specific implementation of this solution will be described in detail below with reference to the accompanying drawings.

[0038] First Implementation Method The first embodiment of the present invention provides a wearable electrode structure. This structure, through a combination of multi-level damping buffer and mechanical trigger base, aims to solve the problem of continuous fluctuation of interface impedance caused by changes in contact pressure during dynamic wearing of existing electrodes. By constructing a mechanical base with a predetermined displacement space, a step-by-step switching of contact states is achieved.

[0039] The wearable electrode provided in this embodiment is based on a layered composite substrate component. See also Figure 1 As shown, the base assembly comprises, from bottom to top, a support layer 1 and a buffer layer 2 covering the surface of the support layer 1. To form a stable mechanical framework and prevent excessive deformation, the density of the support layer 1 is significantly greater than that of the buffer layer 2. For example, the support layer 1 can be made of medical-grade silicone or high-density polyurethane foam, with a density ranging from no less than 180 kg / m³, preferably between 200 kg / m³ and 500 kg / m³. In contrast, the buffer layer 2 can be made of medical-grade memory foam, with a density ranging from 30 kg / m³ to 120 kg / m³. The density difference between the support layer 1 and the buffer layer 2 is preferably no less than 100 kg / m³ to ensure that they exhibit a significant difference in deformation under pressure, thereby creating gradient damping characteristics.

[0040] Regarding thickness and hardness parameters, the support layer 1 can be 3mm to 5mm thick, with a Shore A hardness preferably between 40 and 60 to provide sufficient rigid support. The buffer layer 2 can be 3mm to 10mm thick, with a rebound time controlled between 2 and 4 seconds to adapt to the movement frequency of the human head and provide a comfortable wearing experience. This combination of material parameters is not arbitrarily chosen, but rather designed to form a macroscopic composite structure of "rigid skeleton + soft filling": the high-density support layer 1 limits maximum deformation and provides restoring force, while the low-density buffer layer 2 fills microscopic unevenness and adapts to hair interference.

[0041] To achieve precise control over the electrode contact state, this embodiment provides micro-protrusions 11 on the support layer 1 and forms corresponding grooves 21 on the buffer layer 2. Specifically, the micro-protrusions 11 are disposed on the upper surface of the support layer 1 and located within the groove 21 formed by the buffer layer 2. The micro-protrusions 11 serve as physical limiting references, defining the contact trigger points of the main electrode branches. The width of the groove 21 can be designed to be 0.1 mm to 0.5 mm larger than the width of the micro-protrusions 11. This tolerance range ensures the free displacement space of the micro-protrusions 11 within the groove 21 while avoiding structural instability caused by excessive gaps. The spacing between adjacent micro-protrusions 11 is preferably not less than 2 mm to prevent stress concentration; the height of the micro-protrusions 11 can range from 0.5 mm to 2.0 mm, and this height directly determines the pressure threshold for electrode triggering.

[0042] In a preferred embodiment, the support layer 1 is divided into at least two functional regions on the outer surface of the base component, with different equivalent densities in the support layer 1 located in different functional regions. For example, the support layer 1 can be divided into a central region and an edge region. The equivalent density of the central region can be 250 kg / m³ to 500 kg / m³ to provide stable core support; the equivalent density of the edge region can be 150 kg / m³ to 300 kg / m³ to accommodate the transition of the head's curvature and alleviate local stress concentration. This difference in equivalent density can be achieved through local openings. Specifically, the support layer 1 can form local openings by setting one of a honeycomb structure, a corrugated structure, or a mesh support structure, with an opening ratio ranging from 10% to 60%. Preferably, the opening ratio of the central region is less than that of the edge region, for example, the opening ratio of the central region is 10% to 30%, and the opening ratio of the edge region is 30% to 60%. Through this stiffness gradient design, the electrodes can better conform to complex anatomical sites such as cranial prominences and mastoid structures, avoiding local suspension or excessive compression.

[0043] This embodiment also includes a thin-film pressure sensor layer 3 disposed at the bottom of the support layer 1. This sensor layer 3 is used to monitor the contact pressure applied to the wearable electrode in real time and coordinates with the electrode layer signal to provide feedback on the contact status. The pressure response range of the thin-film pressure sensor layer 3 can be from 0 kPa to 20 kPa, and the sensitivity resolution is preferably not less than 10 Pa. To reliably transmit electrical signals to external devices, this embodiment also provides a flexible conductive path penetrating the support layer 1 and the buffer layer 2. This path can include microchannels disposed within the support layer 1 and the buffer layer 2, and conductive materials, such as liquid metal or conductive silver paste, filled within the microchannels. Furthermore, to optimize interfacial impedance and biocompatibility, the surface of the electrode layer away from the buffer layer 2 can also be covered with a transparent conductive hydrogel layer, the thickness of which can be from 0.5 mm to 1.5 mm.

[0044] The working principle of the above structure lies in establishing a bistable switching mechanism using mechanical limiting. When there is no pressure or the pressure is low, the height of the buffer layer 2 is higher than the micro-protrusions 11. At this time, the main branches of the electrode layer are suspended or only slightly in contact, in a high-impedance monitoring state. (Reference) Figure 5 As shown, when the external pressure reaches the trigger pressure threshold, the buffer layer 2 is compressed until its height is lower than or equal to the height of the micro-protrusion 11. At this time, the main branches of the electrode layer are exposed and come into contact with the object (such as skin) pressing against the buffer layer 2, forming a low-resistance conductive state. Trigger pressure threshold Quantitative design can be performed using mechanical models, for example, satisfying formulas. ,in This is a correction factor (its value can range from 0.8 to 1.2). The Young's modulus of buffer layer 2. The height difference between the buffer layer 2 and the micro-protrusion 11 This represents the initial thickness of buffer layer 2. By configuring the trigger pressure threshold within the range of 3 kPa to 7 kPa, low-frequency noise generated by daily head movements can be effectively filtered out, and the low-impedance path is only opened under effective pressure to achieve a noise threshold effect.

[0045] This embodiment constructs a mechanical substrate with a predetermined displacement space through the density difference between the high-density support layer 1 and the low-density buffer layer 2, and the groove structure 21. The micro-protrusion 11 serves as a physical limiting reference, defining the contact trigger point of the main branch, while the pre-compression state of the buffer layer 2, with its height exceeding that of the micro-protrusion 11, establishes a bistable switching mechanism between the default contact state and the compression-enhanced state. This design utilizes mechanical limiting to filter low-frequency motion noise and clearly distinguishes between the default contact state and the compression-enhanced state, thereby significantly improving signal stability and stimulation reliability in dynamic environments. Simultaneously, the differentiated regional stiffness design achieved through localized openings further enhances the electrode's fit to the complex head contour, ensuring the effective operation of the triggering mechanism throughout the entire area.

[0046] In one configuration, the wearable electrode is used for head EEG monitoring. In this scenario, the electrode needs to be adapted to complex curved surfaces such as skull prominences, mastoid structures, or the temporal region. The trigger pressure threshold is configured to filter motion artifacts generated by everyday head movements. Specifically, the trigger pressure threshold can range from 3 kPa to 7 kPa, covering the typical pressure range generated by everyday head movements, while effectively filtering out minor pressure fluctuations below this threshold. For example, when the electrode is worn in the temporal region, due to the prominent bony prominences and thin skin in this area, the central region of the electrode can use higher stiffness to provide stable support, while the peripheral region can use lower stiffness to adapt to the curved surface transition. The trigger pressure threshold can be configured to approximately 5 kPa, allowing the electrode to maintain stable contact impedance during normal head movements, chewing, and other daily activities, avoiding signal baseline drift caused by slight pressure changes.

[0047] In another configuration, the wearable electrode is used for transcutaneous electroneurostimulation (TENS) scenarios. In this scenario, the electrode is configured to utilize the first conductive path in a low-power monitoring state and the second conductive path in a high-current stimulation state. Specifically, when the external pressure is below the trigger pressure threshold, only the terminal branches contact the skin, forming the first conductive path. At this time, the electrode is in a high-impedance state, suitable for low-power intermittent monitoring. When the external pressure reaches or exceeds the trigger pressure threshold, the buffer layer 2 is compressed, exposing the main branches and making contact with the skin, forming the second conductive path. At this time, the electrode is in a low-impedance state, suitable for high-current output to achieve effective nerve stimulation. For example, in home-based TNS treatment, after wearing the electrode, the patient can perform low-power impedance monitoring in a static state. After confirming good contact, the pressure can be increased by actively pressing the electrode or wearing a pressure headband to exceed the trigger threshold, switching to a low-impedance stimulation mode, thereby extending battery life while ensuring therapeutic efficacy.

[0048] This embodiment also provides a dual-modal power consumption management strategy. In the head EEG monitoring scenario, the electrodes can be configured in continuous monitoring mode, triggering a pressure threshold to identify valid signal acquisition periods. When the detected pressure is below the threshold, the system can determine that there is poor contact or a risk of electrode dislodgement, triggering an alarm or automatically entering standby mode to save power. When the detected pressure is above the threshold, the system determines that the electrode is in a valid wearing state and initiates high-sampling-rate data acquisition. In the transcutaneous electrical nerve stimulation scenario, the electrodes can be configured in intermittent stimulation mode, using a first conductive path for contact status monitoring and a second conductive path for treatment output. The system can monitor impedance changes in real time, automatically switching to stimulation mode when the impedance step drops to a preset range, and returning to monitoring mode after stimulation is completed.

[0049] The technical advantage of this embodiment lies in clarifying the two core application directions of the product: protecting the anti-motion artifact characteristics in EEG monitoring and the bimodal power management characteristics in electrical stimulation. A single claim covers two main commercial embodiments, maximizing the scope of protection. In head EEG monitoring applications, the trigger pressure threshold is configured to filter motion artifacts generated by daily head movements, enabling the electrodes to maintain stable signal acquisition quality in complex head contours and dynamic environments. In transcutaneous electrical nerve stimulation applications, by utilizing a first conductive path in a low-power monitoring state and a second conductive path in a high-current stimulation state, a dynamic balance between power consumption and performance is achieved, ensuring both therapeutic efficacy and extending the device's lifespan.

[0050] Furthermore, this embodiment provides parameter optimization suggestions for different anatomical locations. For example, when the electrode is used in the forehead region, since this region is relatively flat, the trigger pressure threshold can be configured to 3 kPa to 4 kPa, and the thickness of the buffer layer 2 can be selected from 3 mm to 5 mm. When the electrode is used in the mastoid region, since this region has obvious bony protrusions, the trigger pressure threshold can be configured to 5 kPa to 7 kPa, and the support layer 1 can adopt a locally perforated design to enhance fit. When the electrode is used in the temporal region, since this region has a large curvature change and hair interference, the edge area of ​​the electrode can adopt a lower stiffness design, and the perforation rate can be selected from 30% to 60% to alleviate local stress concentration and improve wearing comfort.

[0051] By configuring parameters according to specific scenarios, the optimal performance of the electrodes is ensured in specific usage environments, providing users with a more reliable and comfortable wearing experience.

[0052] Second Implementation Method In the first embodiment, a mechanical trigger base consisting of a high-density support layer 1 and a low-density buffer layer 2, along with micro-protrusions 11, is employed. This scheme can construct a mechanical base with a predetermined displacement space, using the micro-protrusions 11 as physical limiting references to define the contact trigger points of the main branches.

[0053] A second embodiment of the present invention provides a wearable electrode, which, based on the wearable electrode of the first embodiment, further improves the specific pattern structure of the electrode layer to optimize impedance characteristics. The main improvement lies in that the electrode layer has a self-similar topological structure, which includes multiple recursively generated levels, wherein lower-level branches constitute the main branches, and higher-level branches constitute the terminal branches. The terminal branches are disposed on the surface of the buffer layer 2 for contacting an object to form a first conductive path. The main branches are disposed on the top of the micro-protrusions 11 for contacting an object when the buffer layer 2 is compressed to form a second conductive path.

[0054] Specifically, the self-similar topology can be one of H-tree fractals, Koch snowflake fractals, or Sierpinski triangle fractals. (See reference) Figure 2 , Figure 3 As shown, when the self-similar topology adopts an H-tree fractal, the branches from Level 1 to Level 2 can serve as the main branches, and the branches from Level 3 to Level 5 can serve as the terminal branches. This hierarchical allocation directly corresponds to the height difference logic between the micro-protrusion 11 and the buffer layer 2 in Implementation Method 1. For example, in an electrode region with an overall size of 20mm × 20mm, the iteration level n can be 5, and the linear scaling factor s can be 0.5. The linewidth of the electrode layer can be halved step by step to adapt to the current density distribution of different levels. For example, refer to... Figure 4 As shown, the linewidth of the first-level branch can be 200 μm, while the linewidth of the fifth-level branch can be 12.5 μm. This design allows the total electrode length to increase exponentially with the number of levels, reaching approximately 1.86 m when n=5, thus significantly increasing the effective contact perimeter.

[0055] In terms of spatial distribution, the terminal branches are disposed on the surface of the buffer layer 2 to form a first conductive path upon contact with an object. This means that when there is no pressure or the pressure is low, only the terminal branches contact the skin, and the circuit is in a high-impedance monitoring mode. The main branch is disposed on the top of the micro-protrusion 11 to form a second conductive path upon contact with an object when the buffer layer 2 is compressed. When the external pressure reaches the trigger pressure threshold, the buffer layer 2 is compressed, the main branch is exposed and contacts the skin, and the circuit instantly switches to a low-impedance conduction mode. Preferably, the micro-protrusion 11 has an elongated shape matching the length of the main branch, and the micro-protrusion 11 is disposed along the extension direction of the main branch to ensure uniform triggering throughout the entire line.

[0056] Compared to the aforementioned implementations, this implementation introduces a self-similar topology and deeply couples it with the mechanical trigger base, making the step increase in contact area controllable. Therefore, it avoids signal distortion caused by linear impedance drift of traditional planar electrodes under dynamic pressure, resulting in a pressure-driven adaptive conduction mechanism. It maintains basic contact by default, and significantly reduces contact impedance after compression, improving the signal-to-noise ratio and stimulation uniformity in dynamic environments. Furthermore, this type of self-similar structure has inherent conductive redundancy; when contact is poor in some areas due to hair obstruction, wearing displacement, or changes in contact pressure, current can still be conducted through other branch paths, thus avoiding impedance abrupt changes and signal interruption.

[0057] This embodiment also provides specific process implementation methods to ensure the reliability of the above structure. For example, the micro-protrusions 11 can be prepared on the surface of the high-density support layer 1 by laser micro-engraving or precision molding, with the height controlled between 0.5 mm and 2.0 mm and the accuracy controlled at the micrometer level. The electrode layer can be printed using a roll-to-roll optical alignment printing process. First, H-tree fractal electrodes are printed, and real-time correction is performed using optical markers. Then, the substrate with the micro-protrusions 11 is hot-pressed and laminated. The alignment accuracy can be controlled within ±20 micrometers, which is much smaller than the fractal linewidth, ensuring that the fractal backbone accurately falls on the top of the protrusion. This process solution solves the spatial matching problem between the electrodes and the micro-protrusions 11 in the multilayer composite structure and is a key technical link for achieving mass production.

[0058] In summary, this embodiment utilizes the multi-scale characteristics of fractal geometry, where only the distal ends make contact in the default state, while the main body participates in contact after compression, achieving a step-like increase in contact area. This design not only enhances the specificity and reproducibility of the technical solution but also optimizes conductivity stability, providing a dual guarantee of resistance to motion artifacts and redundant conduction for actual products.

[0059] Third Implementation Method A fourth embodiment of the present invention provides a non-invasive neuromodulation intervention device. This embodiment integrates the wearable electrode provided in any of the preceding embodiments into a complete electrical stimulation system, ensuring stable contact and efficient energy transmission between the stimulation electrode and the scalp.

[0060] The non-invasive neuromodulation intervention device provided in this embodiment is referenced. Figure 6 As shown, the device includes a pulse generating unit, a control unit, and a wearable electrode (used herein as a stimulating electrode) according to any of the aforementioned embodiments. The wearable electrode serves as a human-computer interaction device, positioned between the pulse generating unit and the patient's scalp, or integrated into a headband as a separate monitoring module. In a typical system architecture, the stimulating electrode is connected to an electrode lead wire, and the wearable electrode is attached to the surface of the outer shell facing the scalp. When the device is operational, the pulse generating unit generates the current required for treatment, which flows through the wearable electrode, across the patient's epidermis, and to the target area. At this time, the wearable electrode integrated at the bottom of the device plays a crucial role.

[0061] Specifically, the wearable electrode utilizes its bistable triggering mechanism and fractal topology design to ensure stable contact between the electrode and the scalp during electrical stimulation. In the initial stage of device wear or at rest, the electrode is in a low-power monitoring mode, feeding back contact pressure data to the control unit in real time via the thin-film pressure sensor layer 3. If the detected contact pressure is lower than a preset safety threshold, the control unit can prevent the pulse generation unit from starting or issue a warning to the user to adjust the wearing position, thereby avoiding the risk of ineffective stimulation or local overheating due to poor contact. When the user applies appropriate pressure to put the electrode into conduction mode, the main branches and terminal branches of the electrode together form a low-impedance path, at which point the control unit allows the activation of a high-intensity pulse sequence.

[0062] Regarding system signal coordination, this implementation utilizes the multifunctional characteristics of wearable electrodes. The flexible conductive path not only transmits bioelectrical signals but also serves as a feedback loop, transmitting contact impedance data to the control unit in real time. The control unit dynamically adjusts the output parameters of the pulse generation unit based on the impedance data. For example, when a step increase in impedance due to movement is detected, the system can automatically pause stimulation or reduce the output intensity, automatically restarting once the impedance returns to a safe range. This closed-loop control logic significantly improves the safety and effectiveness of transcranial electrical stimulation therapy.

[0063] Furthermore, this embodiment integrates an adaptation mechanism for complex head curvatures. The headband of the non-invasive neuromodulation intervention device can be designed as an adjustable structure, combined with the differentiated stiffness design of the support layer 1 in the wearable electrodes (such as high density in the center and low density at the edges), to adapt to different patients' skull morphologies. For areas that are difficult to fit, such as the mastoid process and temporal region, the locally perforated structure of the electrode buffer layer 2 and the memory foam material can provide additional deformation space, eliminate air gaps, and ensure the consistency of the electric field transmission path.

[0064] This embodiment provides a stable interface contact guarantee for transcranial electrical stimulation therapy. By integrating electrodes with mechanical triggering and fractal conduction characteristics, the device can filter motion artifacts during dynamic treatment, maintain a stable stimulation dose, and improve the consistency and safety of treatment effects. For example, during treatment sessions lasting tens of minutes, even if the patient experiences slight head movement, the electrodes can maintain the stability of the contact state thanks to the micro-protrusion 11 limiting structure, avoiding stimulation interruption or uneven intensity caused by impedance fluctuations.

[0065] This embodiment also provides a system-level calibration method. Before treatment begins, the device can perform a self-test procedure, scanning the pressure distribution on the contact surface through the pressure sensing function of the wearable electrodes, identifying high-pressure and low-pressure points, and guiding the user to fine-tune the tightness of the headband until the pressure distribution across the entire area reaches the ideal range. This function relies on the thin-film pressure sensor array integrated inside the electrodes and its high-resolution (≤10Pa) detection capability, an intelligent feature not found in traditional non-invasive neuromodulation intervention devices.

[0066] In summary, this embodiment integrates a wearable electrode with multi-level damping buffer, a mechanical trigger base, and self-similar fractal electrodes into a non-invasive neuromodulation intervention device, constructing a highly reliable and intelligent neurostimulation system. This system not only solves the problem of unstable contact of traditional electrodes in dynamic environments, but also achieves precise management of the treatment process through system-level signal coordination and safety control logic, providing a novel technical solution for clinical transcranial electrical stimulation applications.

[0067] Finally, it should be noted that those skilled in the art will understand that many technical details have been presented in the embodiments of this patent to facilitate a better understanding of the invention. However, even without these technical details and various variations and modifications based on the above embodiments, the technical solutions claimed in the claims of this patent can be substantially achieved. Therefore, in practical applications, various changes can be made to the above embodiments in form and detail without departing from the spirit and scope of this patent.

Claims

1. A wearable electrode, characterized in that, include: A base assembly comprising a support layer (1) and a buffer layer (2) covering the surface of the support layer (1), wherein the density of the support layer (1) is greater than the density of the buffer layer (2), and grooves (21) are formed on the buffer layer (2). Micro-protrusions (11) are disposed on the support layer (1) and located in the groove (21) formed by the buffer layer (2); The electrode layer has a main branch and a terminal branch. The main branch is located on the top of the micro-protrusion (11), and the terminal branch is suspended on the buffer layer (2). When not under pressure, the height of the buffer layer (2) is higher than that of the micro-protrusion (11); the buffer layer (2) can be compressed when subjected to external pressure so that the main branches of the electrode layer are exposed and come into contact with the object pressing against the buffer layer (2).

2. The wearable electrode according to claim 1, characterized in that, The micro-protrusion (11) has an elongated shape that matches the length of the main branch. The micro-protrusion (11) is arranged along the extension direction of the main branch. The width of the groove (21) is 0.1 mm to 0.5 mm larger than the width of the micro-protrusion (11). The spacing between adjacent micro-protrusions (11) is ≥2mm, and the height of the micro-protrusions (11) ranges from 0.5mm to 2.0mm.

3. The wearable electrode according to claim 1, characterized in that, The electrode layer has a self-similar topology, which includes multiple recursively generated levels, wherein the branches of the lower levels constitute the trunk branches and the branches of the higher levels constitute the terminal branches. The terminal branch is disposed on the surface of the buffer layer (2) for contacting the object to form a first conductive path; The main branch is located on the top of the micro-protrusion (11) and is used to form a second conductive path when the buffer layer (2) is compressed and comes into contact with the object.

4. The wearable electrode according to claim 3, characterized in that, The self-similar topology is one of H-tree fractals, Koch snowflake fractals, or Sierpinski triangle fractals; When the self-similar topology adopts an H-tree fractal, the branches from Level 1 to Level 2 are the main branches, and the branches from Level 3 to Level 5 are the terminal branches. The linewidth of the electrode layers is halved at each level to accommodate the current density distribution at different levels.

5. The wearable electrode according to claim 1, characterized in that, The support layer (1) is made of medical-grade silicone or high-density polyurethane foam, and the buffer layer (2) is made of medical-grade memory foam; The density of the support layer (1) is not less than 180 kg / m³, the density of the buffer layer (2) is 30 kg / m³ to 120 kg / m³, and the density difference between the support layer (1) and the buffer layer (2) is ≥100 kg / m³. The thickness of the support layer (1) is 3 mm to 5 mm, and the Shore A hardness is 40 to 60. The thickness of the buffer layer (2) is 3 mm to 10 mm, and the rebound time is 2 seconds to 4 seconds.

6. The wearable electrode according to claim 1, characterized in that, The support layer (1) divides at least two functional regions on the outer surface of the base assembly, and the equivalent density of the support layer (1) located in different functional regions is different. The functional areas defined in the support layer (1) include a central area and an edge area. The equivalent density of the central area is 250 kg / m³ to 500 kg / m³, and the equivalent density of the edge area is 150 kg / m³ to 300 kg / m³.

7. The wearable electrode according to claim 6, characterized in that, The support layer (1) achieves equivalent density differences in different functional areas through local openings; The local opening is one of a honeycomb structure, a corrugated structure, or a grid support structure; The opening ratio of the local opening is 10% to 60%.

8. The wearable electrode according to claim 7, characterized in that, The aperture ratio of the central region is less than that of the edge region; The aperture ratio of the central region is 10% to 30%, and the aperture ratio of the edge region is 30% to 60%.

9. The wearable electrode according to claim 1, characterized in that, The wearable electrode has a trigger pressure threshold. When the external pressure reaches the trigger pressure threshold, the buffer layer (2) is compressed until the main branch contacts the object. The trigger pressure threshold ranges from 3 kPa to 7 kPa; The trigger pressure threshold satisfies the mechanical model: , The As a correction factor, the The trigger pressure threshold, the The Young's modulus of the buffer layer (2) is... The height difference between the buffer layer (2) and the micro-protrusion (11) is such that... The initial thickness of the buffer layer (2) is... The value range is from 0.8 to 1.

2.

10. The wearable electrode according to claim 1, characterized in that, The base assembly also includes a thin-film pressure sensor layer (3) disposed at the bottom of the support layer (1). The thin-film pressure sensor layer (3) is used to monitor the contact pressure applied to the wearable electrode in real time and coordinate with the electrode layer signal to provide feedback on the contact status. The pressure response range of the thin-film pressure sensor layer (3) is 0 kPa to 20 kPa, and the sensitivity resolution is ≤10 Pa; The wearable electrode also includes a flexible conductive path that runs through the support layer (1) and the buffer layer (2) to transmit the electrical signal of the electrode layer to an external device; The flexible conductive pathway includes microchannels disposed within the support layer (1) and the buffer layer (2), and conductive material filling the microchannels; It also includes a transparent conductive hydrogel layer, which covers the side of the electrode layer away from the buffer layer (2) as an interface that directly contacts the object; The thickness of the transparent conductive hydrogel layer is 0.5 mm to 1.5 mm, and it has conductivity and biocompatibility.

11. The wearable electrode according to claim 1, characterized in that, The wearable electrode configuration is used for head EEG monitoring scenarios and is adapted to complex curved surfaces such as skull protrusions, mastoid structures, or temporal regions. The trigger pressure threshold is configured to filter motion artifacts generated by daily head movements. or, The wearable electrode is configured for transcutaneous electrical nerve stimulation scenarios, and is configured to utilize the first conductive path in a low-power monitoring state and the second conductive path in a high-current stimulation state.

12. A non-invasive neuromodulation intervention device, characterized in that, It has a wearable electrode as described in any one of claims 1 to 11.

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