A method of measuring the impedance of a hydrogel

Abstract

The application provides a method for measuring impedance of a hydrogel, comprising the following steps: powering an electrotherapy signal generator by a power supply to make the electrotherapy signal generator output an electric stimulation signal with preset electric stimulation parameters, and obtaining corresponding average current values of the power supply when the output end of the electrotherapy signal generator is connected to different impedance loads to obtain a data table; powering the electrotherapy signal generator by the power supply to make the electrotherapy signal generator output an electric stimulation signal with the preset electric stimulation parameters, and obtaining an average current value of the power supply when the output end of the electrotherapy signal generator is connected to a test assembly containing a hydrogel to be tested, and recording the average current value of the power supply as a comparison value; querying the data table, and if there is an average current value of the power supply equal to the comparison value in the data table, taking the impedance value of the load corresponding to the average current value of the power supply as the measured impedance value of the hydrogel to be tested. The application can measure the impedance of the hydrogel in a real state, and the measurement result is more accurate.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of hydrogel, in particular, the field of wearable conductive hydrogel, and relates to a method for measuring impedance of hydrogel. BACKGROUND

[0002] Many wearable medical devices need to use hydrogel, which can be pasted on the skin to enable the wearable device to be attached to the surface of the human body, and can have conductive properties to transmit electrical signals (such as electrotherapy) or collect bioelectric signals (such as electrocardiogram and electromyogram).

[0003] For electrotherapy, it is a method of outputting electrical stimulation pulses to the human body to cause electrochemical and / or electrophysiological reactions of the human body to treat diseases. The electrode sheet of the electrotherapy device has conductive hydrogel, and the typical structure of the electrode sheet includes a substrate, a conductive metal layer, and a conductive hydrogel layer.

[0004] Since hydrogel is needed to transmit electrical stimulation energy, the conductive properties, in particular, the impedance of the hydrogel, are required to be designed, and it is generally desired that the smaller the impedance of the hydrogel is, the smaller the transmission loss of the electrical stimulation energy on the hydrogel is.

[0005] However, how to measure the impedance of the hydrogel is a difficult problem, because:

[0006] 1) The hydrogel is a film, and if the size of the probe for measurement is small (such as the commonly used multimeter probe), it is difficult to fully contact and measure accurately, and if the size of the probe is large (such as a flat type), it is also difficult to represent the application situation in the actual product. Moreover, the impedance of the hydrogel shows a certain directionality, and the placement positions of the positive and negative poles of the probe will also cause differences in the measurement results.

[0007] 2) Impedance measurement requires an excitation signal, and it is difficult for an ordinary signal source (such as a signal generator) to simulate the electrical stimulation signal generated by electrotherapy. SUMMARY

[0008] In view of the above-mentioned shortcomings of the prior art, the purpose of the present application is to provide a method for measuring the impedance of hydrogel, which solves the problems of inaccurate measurement of the existing hydrogel impedance measurement method and difficulty of the signal source in simulating the electrical stimulation signal generated by electrotherapy.

[0009] To achieve the above-mentioned purpose and other related purposes, the present application provides a method for measuring the impedance of hydrogel, comprising the following steps:

[0010] The power supply supplies power to the electrotherapy signal generator to enable the electrotherapy signal generator to output an electrical stimulation signal with preset electrical stimulation parameters, and the average current values of the power supply corresponding to different impedance loads connected to the output end of the electrotherapy signal generator are obtained to obtain a data table.

[0011] powering the electrotherapy signal generator by the power supply to make the electrotherapy signal generator output an electrical stimulation signal with the preset electrical stimulation parameters, and obtaining a power supply average current value when an output terminal of the electrotherapy signal generator is connected to a test assembly containing the test hydrogel, denoted as a comparison value;

[0012] querying the data table, if there is a power supply average current value data equal to the comparison value in the data table, then taking the load impedance value corresponding to the power supply average current value data as the measured impedance value of the test hydrogel.

[0013] Optionally, if there is no power supply average current value data equal to the comparison value in the data table, then taking the load impedance value corresponding to the power supply average current value data closest to the comparison value in the data table as the measured impedance value of the test hydrogel.

[0014] Optionally, when the different impedance loads are arranged in order of impedance value, the impedance difference between any two adjacent loads is equal.

[0015] Optionally, the impedance difference between adjacent loads is not greater than 100Ω.

[0016] Optionally, the load includes a pure resistance.

[0017] Optionally, the test assembly containing the test hydrogel further includes an electrode sheet, the electrode sheet including a base sheet, a positive electrode sheet and a negative electrode sheet arranged at intervals, and a positive terminal and a negative terminal arranged at intervals, the base sheet including a first surface and a second surface arranged oppositely, the positive electrode sheet and the negative electrode sheet being arranged on the first surface of the base sheet, the positive terminal and the negative terminal being arranged on the second surface of the base sheet, and the positive terminal being electrically connected to the positive electrode sheet, and the negative terminal being electrically connected to the negative electrode sheet, the test hydrogel spanning the area between the positive electrode sheet and the negative electrode sheet and being electrically connected to the positive electrode sheet and the negative electrode sheet.

[0018] Optionally, the power supply includes a display module for displaying the power supply average current value, or the power supply average current value is obtained by an oscilloscope.

[0019] Optionally, the frequency of the electrical stimulation signal is greater than 5Hz.

[0020] Optionally, the output voltage of the power supply is adjustable.

[0021] Optionally, the output voltage, output frequency and output pulse width of the electrotherapy signal generator are adjustable.

[0022] As described above, the method for measuring hydrogel impedance of the present invention uses a power supply to power an electrotherapy signal generator so that the electrotherapy signal generator outputs an electrostimulation signal with preset electrostimulation parameters, obtains a data table by obtaining the corresponding power supply average current values ​​when the output end of the electrotherapy signal generator is connected to different impedance loads, and obtains the power supply average current value when the output end of the electrotherapy signal generator is connected to the component to be tested containing the hydrogel to be tested, which is recorded as a comparison value; then, by querying the data table, if there is a power supply average current value data equal to the comparison value in the data table, the load impedance value corresponding to the power supply average current value data is used as the measured impedance value of the hydrogel to be tested. The present invention can measure the impedance of the hydrogel in the real state, that is, the shape of the hydrogel conforms to the actual product situation (non-cut sample), and the electrostimulation signal on the hydrogel conforms to the actual product situation (non-multimeter or ordinary signal source), so that the measured hydrogel impedance is more accurate. In addition, the method for measuring hydrogel impedance of the present invention can also be used to measure cut hydrogel samples. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Fig. 1 Shown is a flow chart of a method for measuring hydrogel impedance according to the present invention.

[0024] Fig. 2 Shown is a schematic structural diagram of a component to be tested comprising a hydrogel to be tested.

[0025] Component number description

[0026] Steps S1 to S3

[0027] 1. Hydrogel to be tested

[0028] 2 substrate

[0029] 201 First Surface

[0030] 202 Second Surface

[0031] 3. Positive electrode

[0032] 4 negative electrode sheet

[0033] 5 Positive terminal

[0034] 6 Negative terminal DETAILED DESCRIPTION

[0035] The following describes the embodiments of the present invention through specific examples. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments, and the details in this specification may be modified or altered based on different viewpoints and applications without departing from the spirit of the present invention.

[0036] Referring to Figs. 1-2 It is to be understood that the figures provided in the embodiments are merely schematic to illustrate the basic concept of the present application, and the figures only show the components related to the present application, rather than being drawn according to the number, shape and size of the components in actual implementation, and the shape, number and proportion of the components in actual implementation can be arbitrarily changed, and the layout of the components can be more complex.

[0037] The present application provides a method for measuring the impedance of hydrogel, referring to Fig. 1 , which is shown as a flowchart of the method, comprising the following steps:

[0038] S1: powering the electrotherapy signal generator by the power supply to make the electrotherapy signal generator output an electric stimulation signal with preset electric stimulation parameters, and obtaining the average current value of the power supply when the output end of the electrotherapy signal generator is connected to different impedance loads to obtain a data table;

[0039] S2: powering the electrotherapy signal generator by the power supply to make the electrotherapy signal generator output an electric stimulation signal with the preset electric stimulation parameters, and obtaining the average current value of the power supply when the output end of the electrotherapy signal generator is connected to a test component containing the hydrogel to be tested, denoted as a comparison value;

[0040] S3: querying the data table, if there is a power supply average current value data equal to the comparison value in the data table, then taking the load impedance value corresponding to the power supply average current value data as the measured impedance value of the hydrogel to be tested.

[0041] Specifically, the principle of the method for measuring the impedance of conductive hydrogel of the present application is as follows: for an electric stimulation signal, in the case of the same parameter settings (such as voltage, current, frequency, pulse width, switching ratio, etc.), the power consumption (average current) of the power supply is determined by the load. Generally speaking, the heavier the load (the smaller the impedance), the greater the power consumption; the lighter the load (the greater the impedance), the smaller the power consumption. Therefore, a series of loads with known impedance (such as resistors) can be measured first to obtain the relationship between the load and the power consumption of the power supply, and the test results of the two are recorded to form a data table, such as 500Ω load corresponding to 2.0mA average current of the power supply, 1000Ω load corresponding to 1.0mA average current of the power supply. Then, the hydrogel to be tested or the electrode sheet (in order to measure the actual situation, the hydrogel is usually pasted on the electrode sheet) is used as the load, and the power consumption (average current) of the power supply is viewed under a specific electric stimulation signal. Then, through the above test data table, the corresponding impedance can be obtained, for example, the power consumption of the power supply is also 2.0mA average current, and then it is considered that the impedance of the electrode sheet hydrogel is 500Ω by looking up the table.

[0042] As an example, the method of measuring the impedance of conductive hydrogel of the present application can include the following components for the preparation of the measurement environment: a power supply, an electrotherapy signal generator, a series of pure resistors with known impedance, the hydrogel to be measured, some wires, connectors (such as clips), an oscilloscope, etc. The power supply used requires the ability to adjust the output voltage, has a maximum current limit, and can view the actual output voltage and current, and requires that the output current viewed is an "averaged" output current. The electrotherapy signal generator used is used to output the electrical stimulation signal, and requires the ability to adjust the required parameters of the electrical stimulation signal, which generally includes parameters such as output voltage, frequency, pulse width, etc. Due to the high voltage (up to 80-120V) and short pulse width (1ms or less) of the electrical stimulation signal required for electrotherapy, a high-voltage signal generator can be required. For electrotherapy manufacturers, a self-made electrotherapy device can also be used as a signal generator to directly output the electrical stimulation signal. The electrotherapy signal generator is powered by the power supply described above. The series of pure resistors with known impedance, such as 0Ω, 50Ω, 100Ω, 150Ω, 200Ω, 250Ω, etc., require the ability to withstand the high voltage and power used in electrotherapy, and the smaller the difference between different resistors, the more precise the measurement results. The hydrogel to be measured is usually connected to the electrode pad.

[0043] As an example, the power supply can include a display module for displaying the average current value of the power supply, in which case the oscilloscope is not required. In other embodiments, when the power supply cannot display the average current value of the power supply, the average current value of the power supply can also be obtained through the oscilloscope.

[0044] As an example, in step S1, the power supply is used to power the electrotherapy signal generator to output an electrical stimulation signal with preset electrical stimulation parameters, and the average current value of the power supply when the output end of the electrotherapy signal generator is connected to different impedance loads is obtained to obtain a data table, including the following specific steps:

[0045] S1-1: Connect the power supply to the electrotherapy signal generator and adjust the output characteristics of the power supply to meet the requirements of the electrotherapy signal generator.

[0046] S1-2: Adjust the electrotherapy signal generator to output the actual electrical stimulation signal, for example, 10Hz, 80V, unipolar pulse, pulse width 500μs. The frequency of the electrical stimulation signal is not recommended to be too low, which will cause the average current reading of the power supply to jump, and the frequency of the electrical stimulation signal is generally recommended to be greater than 5Hz.

[0047] S1-3: Provide resistors with different resistance values as loads, connect one of the loads to the electrotherapy signal generator, view the average current of the power supply at this time and make a record, and then test the other resistors in the same way.

[0048] S1-4: Finally, a table of "electrical stimulation parameters-known load-power consumption" is obtained, which has the following form (only an example):

[0049]

[0050] As an example, in the step S2, the electrical therapy signal generator is powered by the power supply to output an electrical stimulation signal with the preset electrical stimulation parameters, and the average current value of the power supply when the output end of the electrical therapy signal generator is connected to a test assembly containing the test hydrogel is obtained, which is recorded as a comparison value, including the following specific steps:

[0051] S2-1: Connect the power supply to the electrical therapy signal generator.

[0052] S2-2: Adjust the electrical therapy signal generator so that it can output the actual electrical stimulation signal.

[0053] S2-3: Connect the test assembly containing the test hydrogel to the output end of the electrical therapy signal generator as a load.

[0054] S2-4: View the average current of the power supply at this time, recorded as a comparison value.

[0055] As an example, please refer to Fig. 2 , which shows a structural schematic diagram of a test assembly containing a test hydrogel 1, which also includes an electrode sheet, the electrode sheet includes a substrate 2, a positive electrode sheet 3 and a negative electrode sheet 4 arranged at intervals, a positive electrode terminal 5 and a negative electrode terminal 6 arranged at intervals, wherein the substrate 2 includes a first surface 201 and a second surface 202 arranged oppositely, the positive electrode sheet 3 and the negative electrode sheet 4 are arranged on the first surface 201 of the substrate 2, the positive electrode terminal 5 and the negative electrode terminal 6 are arranged on the second surface of the substrate 2, and the positive electrode terminal 5 is electrically connected to the positive electrode sheet 3, and the negative electrode terminal 6 is electrically connected to the negative electrode sheet 4, and the test hydrogel 1 spans the area between the positive electrode sheet 3 and the negative electrode sheet 4 and is electrically connected to the positive electrode sheet 3 and the negative electrode sheet 4.

[0056] As an example, in the step S3, the data table is queried, if there is an equal power supply average current value data in the data table as the comparison value, the load impedance value corresponding to the power supply average current value data is taken as the measured impedance value of the test hydrogel. And if there is no power supply average current value data equal to the comparison value in the data table, the load impedance value corresponding to the power supply average current value data closest to the comparison value in the data table is taken as the measured impedance value of the test hydrogel.

[0057] As an example, in the step S1-3 described above, when different impedance loads are arranged in order according to the impedance values, the impedance difference between any two adjacent loads is equal, for example, for a series of loads with impedance values of 0Ω, 50Ω, 100Ω, 150Ω, 200Ω, 250Ω, the impedance difference between any two adjacent loads is 50Ω. In other embodiments, the impedance difference between adjacent loads can be adjusted as needed, and the impedance difference between any two adjacent loads can also not be equal. In this embodiment, the impedance difference between adjacent loads is preferably not greater than 100Ω, and more preferably less than 50Ω. Among them, the smaller the impedance difference between adjacent loads, the more accurate the result when the average power current value data in the data table corresponding to the load impedance value closest to the comparison value is selected as the measured impedance value of the water gel to be measured when there is no average power current value data equal to the comparison value in the data table.

[0058] In summary, the method for measuring the impedance of the water gel of the present application uses a power supply to power the electrotherapy signal generator to make the electrotherapy signal generator output an electrical stimulation signal with preset electrical stimulation parameters, obtains the average power current value corresponding to the connection of different impedance loads at the output end of the electrotherapy signal generator to obtain a data table, and obtains the average power current value when the output end of the electrotherapy signal generator is connected to the test component containing the water gel to be tested, which is recorded as the comparison value. Then by querying the data table, if there is average power current value data equal to the comparison value in the data table, the load impedance value corresponding to the average power current value data is taken as the measured impedance value of the water gel to be tested. The present application can measure the impedance of the water gel in a real state, that is, the form of the water gel conforms to the actual product situation (non-cutting sample), and the electrical stimulation signal on the water gel conforms to the actual product situation (non-ohmmeter or ordinary signal source), so that the measured impedance of the water gel is more accurate. In addition, the method for measuring the impedance of the water gel of the present application can also be used to measure the cut water gel sample. Therefore, the present application effectively overcomes the shortcomings of the prior art and has high industrial utilization value.

[0059] The above embodiments only exemplarily illustrate the principles and effects of the present application, and are not used to limit the present application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical idea disclosed by the present application should be covered by the claims of the present application.

Claims

1. A method of measuring the impedance of a hydrogel, characterized by, The method comprises the following steps: a power supply is used to supply power to an electrotherapy signal generator to make the electrotherapy signal generator output an electrical stimulation signal with preset electrical stimulation parameters, and to obtain the average current value of the power supply when the output terminal of the electrotherapy signal generator is connected to different impedance loads to obtain a data table; the power supply is used to supply power to the electrotherapy signal generator to make the electrotherapy signal generator output an electrical stimulation signal with the preset electrical stimulation parameters, and to obtain the average current value of the power supply when the output terminal of the electrotherapy signal generator is connected to a test assembly containing a test hydrogel, denoted as a comparison value; the data table is queried, and if there is an average current value of the power supply in the data table that is equal to the comparison value, the impedance value of the load corresponding to the average current value of the power supply is taken as the measured impedance value of the test hydrogel; The test assembly containing the test hydrogel further comprises an electrode sheet, and the electrode sheet comprises a substrate, a positive electrode sheet and a negative electrode sheet arranged at intervals, and a positive electrode terminal and a negative electrode terminal arranged at intervals. The substrate comprises a first surface and a second surface arranged oppositely. The positive electrode sheet and the negative electrode sheet are arranged on the first surface of the substrate. The positive electrode terminal and the negative electrode terminal are arranged on the second surface of the substrate, and the positive electrode terminal is electrically connected to the positive electrode sheet, and the negative electrode terminal is electrically connected to the negative electrode sheet. The test hydrogel spans the area between the positive electrode sheet and the negative electrode sheet and is electrically connected to the positive electrode sheet and the negative electrode sheet. The frequency of the electrical stimulation signal is greater than 5 Hz.

2. The method of measuring the impedance of a hydrogel according to claim 1, wherein: If there is no average current value of the power supply in the data table that is equal to the comparison value, the average current value of the power supply in the data table that is closest to the comparison value is taken as the measured impedance value of the test hydrogel.

3. The method of measuring the impedance of a hydrogel according to claim 1, wherein: When the different impedance loads are arranged in order of impedance value, the impedance difference between any two adjacent loads is equal.

4. The method of measuring the impedance of a hydrogel according to claim 3, wherein: The impedance difference between adjacent loads is not greater than 100 Ω.

5. The method of measuring the impedance of a hydrogel according to claim 1, wherein: The load comprises a pure resistance.

6. The method of measuring the impedance of a hydrogel according to claim 1, wherein: The power supply comprises a display module for displaying the average current value of the power supply, or the average current value of the power supply is obtained through an oscilloscope.

7. The method of measuring the impedance of a hydrogel according to claim 1, wherein: The output voltage of the power supply.

8. The method of measuring the impedance of a hydrogel according to claim 1, wherein: The output voltage, output frequency and output pulse width of the electrotherapy signal generator are adjustable.

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