22 results about "Contact impedance" patented technology

The application discloses an electrooculogram signal collection and analysis system and method, relates to the technical field of bioelectric signal collection, and comprises a data processing system, a CPU central processing circuit, a medium-frequency signal generation circuit, an output circuit, a signal collection system and an electrooculogram wave analysis system. The CPU central processing circuit is sequentially connected with the medium-frequency signal generation circuit and the output circuit. The output circuit is adapted to a target to be measured through the signal collection system. The signal collection system transmits collected signals to the electrooculogram wave analysis system, and feeds back the pretreated signals to the CPU central processing circuit. The CPU central processing circuit is in data intercommunication with the data processing system, and closed-loop feedback is performed through the data processing system. The application reduces the contact impedance of the flexible electrode, improves the motion artifact suppression capability, improves the prescription optimization efficiency, and improves the treatment efficiency through clinical verification.

The application discloses an IGBT module contact impedance measurement method based on a power cycle circuit, wherein the contact resistance between a pressure contact piece in any phase bridge arm and upper and lower bridge arms is R1, the contact resistance between the pressure contact piece and an inductor is R2, and the equivalent resistance between the upper and lower bridge arms is R3; a measurement current source is connected between the upper and lower bridge arms of any phase bridge arm, and a measurement current I1 is output based on the measurement current source, so that the measurement current I1 flows through the inductor, the pressure contact piece and the lower bridge arm in sequence, so as to solve the problem that the contact resistance is generated when the power terminal of the IGBT module is connected with the power cycle circuit in a pressure contact mode, the contact pressure value is inversely proportional to the contact resistance value, the resistance loss of the overall circuit is increased, the temperature at the pressure contact position is sharply increased, and the fault hidden danger of the test operation of the power cycle equipment is caused.

The application discloses a novel conductive chest strap preparation method, a permeable conductive reinforcing composition and a surface micro-erosion pretreatment gel. The method first weaves a segmented belt containing stretchable areas and non-stretchable electrode collection areas; then a thixotropic pretreatment gel is coated on the surface of the electrode area, a micro-erosion layer is formed on the surface of the fiber by using a solvent; then the permeable conductive reinforcing composition is forcedly absorbed into the fiber bundle under the condition of vacuum negative pressure; finally, the resin and the fiber form an interpenetrating network and chemical bonding through gradient temperature curing. Through the synergistic effect of physical structure restriction and micro-chemical anchoring, the application solves the problems of easy delamination and cracking of the conductive layer and unstable contact impedance in the traditional process, meanwhile, the gel characteristics are used to block the solvent wicking and diffusion, the elasticity of the substrate is effectively protected, and the durability and signal collection accuracy of the product are significantly improved.

The application discloses a preparation method of an electric field-induced hydrogel electrode and application thereof. The method mainly uses polyvinyl alcohol as a base material, combines conductive media (PEDOT:PSS, NaCl or CaCl), a chemical crosslinking agent (glutaraldehyde) and a reversible coordination crosslinking agent (sodium tetraborate decahydrate), and introduces tannic acid to improve adhesion. The core of the method is that the electric field-induced hydrogel is added dropwise to the surface of an electrode to be grown, a redox reaction is induced in a cathode area by applying an electric field, the pH value of a solution is rapidly increased, the coordination crosslinking of sodium tetraborate is activated, and the hydrogel is rapidly and in-situ solidified on the surface of the electrode. The hydrogel electrode prepared by the method has high tensile property, high conductivity and self-repairing characteristics, has low contact impedance and high signal-to-noise ratio, and can be used as a high-performance flexible electrode and applied to detection of electrocardiosignal and other electrophysiological signals, and has obvious advantages compared with commercial electrodes.

This invention relates to the field of battery testing technology, specifically to a method, apparatus, and system for recycling and testing lithium battery modules. The invention obtains the voltage rebound coefficient at each time point after the current cutoff; based on the time characteristics of different times after the current cutoff and different preset response time constants, it obtains the unit step response function value at each response time constant at each time point after the current cutoff; based on the unit step response function values ​​at all response time constants and the voltage rebound coefficient at different times after the current cutoff, it obtains the optimal voltage drop component for different response time constants and obtains the abnormal residual energy value; combined with the electrode temperature distribution at different times, it obtains the contact impedance coupling coefficient and diffusion impedance coupling coefficient; and performs recycling and testing on the lithium battery module. This invention improves the accuracy of module recycling by accurately analyzing the abnormal residual energy value and using a thermoelectric characteristic coupling criterion based on the electrode temperature rise rate.

This invention relates to the field of welding early warning technology, and more particularly to a spatter early warning system for projection welding based on arc acoustic signal monitoring. The system includes: a data acquisition module for acquiring arc acoustic signals, electrode surface condition data, and noise baseline during non-welding periods; an acoustic feature extraction module for generating acoustic feature signal-to-noise ratio estimates; an acoustic path state determination module for determining acoustic path state indices based on electrode wear indices and signal-to-noise ratio estimates; an acoustic feature processing module for determining correction methods for acoustic feature parameters by combining dynamic contact impedance change rate; and an early warning module for providing spatter early warning based on the corrected acoustic feature parameters. This invention achieves dynamic compensation and interference suppression of acoustic feature parameters by integrating multi-parameter adaptive correction techniques that combine electrode wear state, acoustic path attenuation characteristics, and dynamic contact impedance change rate.

The invention provides a flexible dry electrode material, a flexible dry electrode and a preparation method, equipment and device of the flexible dry electrode. The preparation method of the flexible dry electrode material comprises the steps that a 2D flexible substrate material is provided; coating a conductive coating with a preset thickness on the surface of the 2D flexible substrate material through a surface coating process, and forming a continuous conductive layer on the surface of the 2D flexible substrate material, so that the 2D flexible substrate material with the continuous conductive layer forms a flexible dry electrode material; the flexible dry electrode material is used for collecting electroencephalogram signals. The flexible dry electrode material is formed by coating the continuous conducting layer with the preset thickness on the 2D flexible substrate material, the electrode-skin contact resistance of the flexible dry electrode material can be as low as 50 k omega or below, and the problem that the electrode-skin contact resistance is large when a traditional dry electrode is used for collecting electroencephalogram signals is solved; and the application reliability of the dry electrode in the field of high-precision and long-time electroencephalogram monitoring is improved.

The application discloses a kind of real-time monitoring impedance electric stimulation system, belong to medical electronic technical field;The system includes signal generation module, signal multiplexing module, signal acquisition module, impedance extraction module, impedance calculation module and intelligent feedback control module;Signal generation module simultaneously generates treatment stimulation signal and frequency orthogonal impedance monitoring signal;Signal multiplexing module is combined after two kinds of signals and is applied to human body by electrode;Signal acquisition module acquires mixed signal containing physiological response and impedance information;Impedance extraction module accurately extracts impedance modulation component from mixed signal using digital lock-in amplification technology;Impedance calculation module calculates electrode-tissue contact impedance in real time;Intelligent feedback control module carries out multistage threshold judgment according to impedance value, realizes alarm, parameter adjustment and safety protection function;The application realizes the synchronization of treatment and monitoring, improves the safety and reliability of system, is applicable to various electric stimulation medical equipment.

This invention provides a method and system for physiological signal pattern recognition in anesthesiology, relating to the field of physiological signal recognition technology. The method includes the following steps: injecting an alternating current microcurrent into an electrode pad connected to the patient's skin; calculating the contact impedance at the interface between the skin and the electrode pad and extracting impedance fluctuation parameters from atypical impedance fluctuations; dynamically adjusting a compensation strategy for the target physiological signal based on the impedance fluctuation parameters; compensating for waveform distortion caused by changes in contact impedance to the target physiological signal using the adjusted compensation strategy; and identifying the patient's physiological state based on the compensated target physiological signal. This invention aims to solve the technical challenge in clinical anesthesiology where atypical fluctuations in the impedance characteristics of the patient's skin-electrode contact interface lead to zero-point drift and waveform distortion of physiological signals, thus affecting the accuracy of anesthesia depth assessment, and significantly improves the accuracy and reliability of physiological signal pattern recognition in anesthesiology.

A system (100) for a vehicle seat for the electrical stimulation of a user (400) is described, comprising: a seat base (110) and / or a seat back (120) of the vehicle seat, the respective surfaces of which are formed by a seat cover, a plurality of electrodes (112, 114, 122) which are arranged directly below the seat cover of the seat base and / or the seat cover of the seat back such that at least by means of a subset of the plurality of electrodes (112, 114, 122) potential pain areas of the user (400) can be stimulated, and the subset of electrodes is configured to form an electrical contact with a skin surface of the user (400), and an electrical stimulation module (200, 210) which is electrically coupled to at least the subset of electrodes (112, 114, 122);wherein the electrical stimulation module (200, 210) is configured to apply pulsed electrical currents, with a pulse sequence for pain-reducing electrical stimulation of the user, between, in particular, specific pairs of electrodes (112, 114, 122) of the subset of electrodes, in particular to the user's skin surface, and wherein the electrical stimulation module (200, 210) is configured to automatically adapt the pulsed electrical currents to a contact impedance, determined in particular by means of the electrical stimulation module (200, 210), between at least one pair of the subset of electrodes (112, 114, 122) and the user's skin surface; and / or to adapt the pulsed electrical currents to a predetermined user profile (400).

The application relates to the technical field of electromagnetic compatibility filters, and discloses a filter modular design optimization method and system, which comprises the following steps: obtaining a component connection relationship, a component port position, a busbar connection path and a cabinet installation position divided according to pre-assembled filter components, establishing an interface relationship table and an initial filter topology; identifying a component connection interface, a busbar transition interface and a cabinet installation interface, extracting an interface length, a contact position, a ground corresponding position and an adjacent conductor corresponding relationship, and forming an interface state description result; mapping each interface into a distributed inductance, a distributed capacitance and a contact impedance, generating a parasitic reconstruction topology; identifying a target interface and determining an interface constraint condition, updating to obtain an assembled filter topology, and outputting a component assembly sequence, a connection path and an installation position; and the application improves the consistency between a filter design result and a whole machine assembly result under modular reuse conditions, and reduces the risk of prototype rectification.

This disclosure relates to the measurement of bioimpedance and contact impedance. Accurate measurement of bioimpedance is important for sensing the characteristics of an organism. Unfortunately, contact impedance significantly reduces the accuracy of bioimpedance measurements. To address this problem, circuitry for implementing four-wire impedance measurements can be configured to perform multiple current measurements. These multiple current measurements establish a system of equations that allow the derivation of unknown bioimpedance and contact impedance. The result is accurate bioimpedance measurement unaffected by large contact impedance. Furthermore, poor contacts with undesirable high impedance can be identified.

This invention relates to the field of electrical safety testing technology, and discloses a comprehensive testing device and method for power supply filters. The method includes: performing closed-loop correction of the contact impedance of the test circuit before applying the test voltage; intelligently selecting parallel or sequential excitation mode to apply high voltage based on pre-test results; acquiring leakage current waveforms in real time during the test, comparing them with preset insulation failure precursor characteristics, and rapidly cutting off the high voltage within microseconds through an independent hardware channel during matching; calculating the dispersion of batch leakage current after the test and comparing it with a threshold adaptively updated based on historical data. The corresponding device includes a high-voltage matrix switch network, an adaptive tooling matrix, a safety monitoring module, and a host computer. This invention achieves reliable test connection assurance, proactive safety protection during the test process, and intelligent optimization capabilities for the test strategy.

This invention discloses an online compensation method and system for aging of ion-conducting continuous dielectric skin. The method includes the following steps: S1, determining whether the system has entered a non-interactive idle state; S2, constructing a complex impedance spectrum matrix containing amplitude and phase information; S3, outputting an aging drift vector including electrode contact impedance; S4, based on the aging drift vector, updating the mapping weights or sensitivity matrix in the tactile inversion model in real time to compensate for tactile perception deviations caused by material aging; S5, monitoring based on the output electrode contact impedance, and when the contact impedance of any electrode exceeds a predetermined threshold, cutting off the failed electrode channel, and reconstructing the failed area using virtual electrode mapping based on the electric field distribution formed by the remaining electrodes to maintain the integrity of tactile perception. This invention aims to solve the problem of tactile perception drift caused by the evolution of materials and interfaces over time in ion-conducting skin, achieving low-cost online health assessment and adaptive compensation.

The application belongs to the technical field of biomedical engineering, and discloses a full-automatic high-density electroencephalogram intelligent monitoring system based on a cooperative mechanical arm, which comprises the following modules: a cooperative mechanical arm module, a high-density electroencephalogram acquisition module, a visual positioning module, a terminal execution and sensing module, and a central control unit. Through a full-automatic electrode positioning and placement process, the wearing and debugging time of 256 electrodes is greatly shortened, the energy consumption of medical staff is effectively reduced, and the fatigue of subjects caused by long-term wearing is avoided. With the aid of a non-rigid registration algorithm in visual recognition and three-dimensional model reconstruction and an optimization algorithm of intelligent path planning, the accurate and uniform distribution of electrodes on a complex scalp geometric surface is ensured, the positioning deviation between different operators is significantly reduced, and the positioning consistency is improved. Through signal closed-loop monitoring and an active fine-tuning mechanism, the contact impedance and related contact quality of a single electrode are monitored in real time.

This invention relates to the field of semiconductor device testing technology, and discloses a method and system for identifying gate leakage current in GaN chips based on machine learning. The method includes: applying a test signal to the chip test pads to obtain the physical contact impedance, and calculating the transient time constant by combining it with parasitic capacitance; applying a stepped voltage to the gate of the chip under test to record the leakage current, generating a discrete leakage current sequence; determining the sliding window size based on the transient time constant, fitting and differentiating the leakage current sequence within the window to establish an initial phase space composed of the leakage current and its derivative; performing an affine transformation on the initial phase space using the transient time constant to generate a calibration phase space trajectory; converting the trajectory into a two-dimensional feature matrix and inputting it into a pre-trained machine learning classification model, outputting a predicted probability to trigger sorting. This invention effectively identifies transient charge trapping anomalies caused by deep-level traps by eliminating interference from probe contact impedance fluctuations, reducing the risk of missed detection of potentially faulty chips and misjudgment of normal chips.

The utility model relates to electronic connector contact impedance on -line testing arrangement belongs to impedance testing arrangement technical field, including testing arrangement body, testing arrangement body output is equipped with the connecting wire, and the other end of connecting wire is equipped with the testing head, and testing arrangement body one side is equipped with the mounting cover, and the mounting cover inside is equipped with the storage subassembly that can store the connecting wire, and the storage subassembly includes storage shaft and connecting cover, and storage shaft rotatory mounting is in the mounting cover inside, and the limit hole is equipped on storage shaft, and the limit hole is connected with the connecting wire, and connecting cover installs in mounting cover one end, and the disc spring is connected on storage shaft, and the filter screen is clamped in testing arrangement body one side, the utility model discloses through storage subassembly, mounting cover, elastic clamping piece, realizes the automatic winding function of wire, avoids the wire material in disorder, and simultaneously can according to actual use demand flexible regulation wire length, significantly improves the applicability, can properly store the testing head when not using, effectively avoids the damage, prolongs its life.

This invention relates to the field of online monitoring technology, and more particularly to an online monitoring method and system for connector contact impedance. The method includes: acquiring initial material property descriptions of the connector surface and internal layers; constructing a test signal propagation model; determining the correlation curves between penetration capability and frequency, and resolution and frequency; extracting key inflection points from the correlation curves; adjusting simulation parameters and optimizing the frequency response feature set according to the attenuation values ​​of the corresponding frequency bands; separating frequency band subsets sensitive to degradation processes; grouping the response modes within the frequency band subsets; identifying sets of similar response modes; and generating a dynamic frequency band combination scheme; performing signal injection and reflection coefficient measurement based on the dynamic frequency band combination scheme to obtain microscopic change indicators of contact impedance. This method solves the problems of simultaneously balancing signal penetration capability and detection resolution, and the inability to dynamically adapt to changes in connector structural impedance, achieving adaptive online precise monitoring of connector contact impedance.

The application belongs to the technical field of manufacturing process and online quality control of ion conductive intelligent skin module, and particularly relates to integrated injection molding and online complex impedance quality control process of full dielectric ion skin module. In view of the problems of insufficient bonding force, invisible micro air gap and pollution of the flexible electrode-ion conductive continuous medium interface in injection molding, the application completes in-situ injection molding of ion conductive continuous medium within the free radical decay time window Δt after plasma activation to induce molecular-level fusion of the interface; micro air gap is eliminated under high pressure during the injection molding pressure maintaining period, multi-frequency complex impedance sweep is performed on the edge electrode, and contact impedance Rc, equivalent series resistance Rs and phase angle peak frequency f_peak are extracted as release criteria; the pressure maintaining time, pressure maintaining pressure and mold temperature are adjusted in real time according to the sweep result, active closed-loop optimization and traceable quality control of the interface quality are realized, the consistency and yield of the ion skin module are improved, and production history data is provided for life compensation algorithm.

The application discloses a flexible wearable sensor for detecting net photosynthetic rate of plants and a preparation method and application thereof, and the sensor is composed of a fixing layer, a substrate layer, an electrode layer and a conductive layer, and stretchable net structures are formed at both ends of the substrate layer; the electrode layer is a concentric circle sensing electrode, so that a uniform radial alternating current field is generated, and the conductive layer is closely attached to the surface of the leaf to reduce the interface contact impedance. The detection system constructed by the sensor can effectively solve the technical problem that the net photosynthetic rate of plants cannot be monitored in a long-term, non-destructive, real-time and in-situ manner in the prior art according to the high correlation between the alternating impedance parameters of the plant leaves under a specific characteristic frequency and the ion exchange of the leaf cells, by in-situ collection of the impedance change of the leaves, and by combination of environmental parameters, to calculate the net photosynthetic rate.

This invention discloses a flexible electrode, its preparation method, and its applications. The flexible electrode can be attached to human skin to detect physiological electrical signals. It comprises an upper electrode material, a porous support layer, and a lower electrode material stacked sequentially. The upper and lower electrode materials are self-healing electrode materials, comprising polyborosiloxane, conductive microparticles, and a coupling agent. The porous support layer is a porous SEBS film. The flexible electrode of this invention is human-friendly and can be used in complex motion scenarios where conventional commercial electrodes are difficult to apply. It overcomes problems such as electrode detachment due to movement, skin electrode contact impedance easily affected by deformation, interference from sweat and temperature, and skin allergies caused by long-term wear. It exhibits good skin conformability, high and low temperature performance, wide application scenarios, and excellent stability in use.