Device for measuring contact impedance between myoelectric multi-channel electrodes and biological organisms

Abstract

The present application provides a device for measuring the contact impedance between an electromyographic multi-channel electrode and a biological organism, comprising: a control processor circuit, a power supply circuit, a measurement circuit, a first multi-way switch, a second multi-way switch, a third multi-way switch, a fourth multi-way switch, an electrode interface, and a ground interface; the control processor circuit is connected to other circuits and switches; the electrode interface is configured with a multi-way connector, and the multi-way connector is respectively connected to the first multi-way switch, the third multi-way switch, and the fourth multi-way switch; the measurement circuit is also respectively connected to the second multi-way switch and the ground interface; the second multi-way switch is also connected to the first multi-way switch; the first multi-way switch is also respectively connected to the third multi-way switch, the fourth multi-way switch, and the electrode interface; the third multi-way switch and the fourth multi-way switch are respectively connected to the electrode interface. The present application improves the accuracy of the contact impedance of the determined multi-channel electrode.

Description

Technical Field

[0001] The present application relates to the technical field of contact impedance measurement devices, and in particular to a device for measuring contact impedance between an electromyographic multi-channel electrode and a biological organism. Background Art

[0002] Bioelectricity is an electrical phenomenon presented by organisms. For example, the bioelectricity of the human body comes from the function of cells. Under certain conditions, bioelectricity is regular, and a certain physiological process corresponds to an electrical reaction. According to the change process and law of bioelectricity, it can be inferred whether the physiological process is in a normal state, thereby judging the health status of the human body.

[0003] Bioelectric technology is widely used in the field of medical monitoring, such as electrocardiogram, electroencephalogram, and electromyography. Bioelectric signals are transmitted to the body surface through human tissue. When measuring bioelectricity, conductive electrodes need to be fixed on the surface of the human body (such as skin). In the entire transmission path of bioelectric signals, human tissue is regarded as a good conductor, and its impedance will change accordingly according to the frequency. The contact impedance between the electrode and the skin varies from millions of ohms to tens of ohms. Therefore, the contact impedance between the electrode and the skin directly affects the quality of the bioelectric signal. At the same time, it is generally recognized that the size of the contact impedance between the electrode and the skin directly reflects the contact quality between the electrode and the skin.

[0004] Before and after using the bioelectric signal acquisition equipment, it is necessary to use a resistance measuring device to measure the contact resistance between the electrode and the skin once. This helps us understand the contact status between the electrode and the skin during the test.

[0005] In the field of electrocardiography, electroencephalography, electromyography, and EIT imaging, the two-electrode method is often used to measure the contact impedance between the electrode and the skin. The general process of the two-electrode method is as follows:

[0006] The two electrodes include an excitation electrode and a measurement electrode. The excitation current meter is I, and the measured voltage difference is V. Then, based on the fact that the boundary voltage difference is equal to the product of the contact impedance value and the current I, the contact impedance modulus Z is calculated. The two-electrode method uses the measured contact impedance modulus Z as the resistance between the two electrodes, which is also the contact impedance.

[0007] This method generally determines the size of the contact impedance through a single measurement. Since the measurement circuit has a certain working range, a single measurement can only cover a part of the impedance range to be measured. The measured value is often inconsistent with the actual contact impedance, and the measurement accuracy is low, which leads to the failure of EMG signal acquisition. In addition, the traditional two-electrode method is only applicable to measuring the contact impedance between a single EMG channel electrode and the skin when a pair of differential electrodes are attached to the surface of human skin. It cannot be applied to scenarios with high-density EMG acquisition requirements, that is, when there are a large number of electrode channels (such as 64 or 128 channels), the contact impedance of each channel must be measured quickly and separately. Summary of the invention

[0008] The present application provides a device for measuring contact impedance between an electromyographic multi-channel electrode and a biological body, which is used to solve the problems in the above-mentioned background technology. The device comprises: a control processor circuit (01), a power supply circuit (11), a measurement circuit (21), a first multi-way switch (31), a second multi-way switch (32), a third multi-way switch (35), a fourth multi-way switch (36), an electrode interface (41), and a ground interface (42);

[0009] The control processor circuit (01) is connected to other circuits and switches;

[0010] The electrode interface (41) is provided with a multi-way connector (411), and the multi-way connector (411) is respectively connected to the first multi-way switch (31), the third multi-way switch (35), and the fourth multi-way switch (36);

[0011] The measuring circuit (21) is also connected to the second multi-way switch (32) and the grounding interface (42) respectively;

[0012] The second multi-way switch (32) is also connected to the first multi-way switch (31);

[0013] The first multi-way switch (31) is also connected to the third multi-way switch (35), the fourth multi-way switch (36), and the electrode interface (41) respectively;

[0014] The third multi-way switch (35) and the fourth multi-way switch (36) are respectively connected to the electrode interface (41).

[0015] Optionally, the measuring device further comprises a compensation circuit (22), wherein the compensation circuit (22) comprises an amplifier (221), a first single-pole single-throw switch (222), a first resistor (223), a second resistor (224), a third resistor (225), and a fourth resistor (226); a control pin of the first single-pole single-throw switch (222) is connected to the control processor circuit (01), and a control signal 0133 issued by the control processor circuit (01) can control the opening and closing of the first single-pole single-throw switch (222); one end of the first resistor (223) is connected to the positive power supply V11 output by the power supply circuit (11), and the other end of the first resistor (223) is connected to the amplifier The first embodiment is a schematic diagram of a first embodiment of the present invention, wherein the first resistor (224) is connected to the positive input terminal +IN of the amplifier (221); one end of the second resistor (224) is connected to the positive input terminal +IN of the amplifier (221), and the other end of the second resistor (224) is connected to the negative power supply terminal V12 of the power supply circuit (11); one end of the third resistor (225) is connected to an output terminal of the second multi-way switch (32) for receiving the first excitation signal T11, and the other end is connected to the reverse input pin -VIN of the amplifier (221); one end of the fourth resistor (226) is connected to the reverse input pin -VIN of the amplifier (221), and the other end is connected to the output pin Vout of the amplifier (221) and the input terminal of the first multi-way switch (31).

[0016] Optionally, the measuring device further comprises a calibration circuit (27), wherein the calibration circuit (27) comprises a standard resistor (271) and a second single-pole single-throw switch (272); one end of the standard resistor (271) is connected to one end of the second single-pole single-throw switch (272), the other end of the standard resistor (271) is connected to an output pin of the second multi-way switch (32), the other end of the second single-pole single-throw switch (272) is connected to the measuring circuit (21), and the second single-pole single-throw switch (272) is also communicatively connected to the control processor circuit (01).

[0017] Optionally, the measuring device further comprises an alarm circuit (24), the alarm circuit (24) comprising a buzzer (241), a third diode (242), and an N-channel MOSFET (243); the gate of the N-channel MOSFET (243) is communicatively connected to the control processor circuit (01), the drain of the N-channel MOSFET (243) is connected to the negative electrode of the buzzer (241), and the source of the N-channel MOSFET (243) is connected to the negative electrode V12 of the power supply circuit (11); one pin of the buzzer (241) is connected to the positive electrode V11 of the power supply circuit (11), and the other pin is connected to the drain of the N-channel MOSFET (243); the cathode of the third diode (242) is connected to the positive electrode of the buzzer (241), and the anode of the third diode (242) is connected to the negative electrode of the buzzer (241).

[0018] Optionally, the grounding interface (42) comprises a grounding socket (421) and a second diode (422); the grounding socket (421) is connected to a grounding electrode; the grounding socket (421) is used to receive a first excitation return signal T12 returned by the grounding electrode; the cathode of the second diode (422) is connected to the grounding socket (421), and the anode of the second diode (422) is connected to the negative electrode V12 terminal of the power supply circuit (11).

[0019] Optionally, each channel of the multi-way connector (411) is provided with a first diode (412); the cathode of each of the first diodes (412) is connected to a corresponding pin of the multi-way connector (411), and the anode is connected to the negative electrode V12 terminal of the power supply circuit (11).

[0020] Optionally, the measurement circuit (21) comprises an impedance measurement chip (211), wherein the impedance measurement chip (211) is configured with an impedance measurement circuit and a digital signal processor that are connected to each other; the digital signal processor is connected to the control processor circuit (01), and the impedance measurement circuit is respectively connected to the second multi-way switch (32) and the ground interface (42).

[0021] Optionally, the measuring device further comprises a wireless transmission circuit (25), wherein the wireless transmission circuit (25) comprises a wireless module (251), and the wireless module (251) is respectively communicatively connected to the control processor circuit (01) and the terminal device.

[0022] Optionally, the measuring device further comprises a storage circuit (26), wherein the storage circuit (26) comprises a self-pop-up MicroSD card slot (261) and a memory (262), wherein the self-pop-up MicroSD card slot (261) is communicatively connected to the memory (262) and the control processor circuit 01 respectively.

[0023] Optionally, the device further comprises a first button (43), a second button (44), and a third button (45); the first button (43) comprises a first light touch switch (431) and a fourth diode (432), the second button (44) comprises a second light touch switch (441) and a fifth diode (442), and the third button (45) comprises a third light touch switch (451) and a sixth diode (452); the first light touch switch (431), the second light touch switch (441), and the third light touch switch ( 451) is connected to the control processor circuit (01); the cathode of the fourth diode (432) is connected to the pin of the first touch switch (431), and the anode is connected to the negative electrode V12 of the power supply circuit (11); the cathode of the fifth diode (442) is connected to the pin of the second touch switch (441), and the anode is connected to the negative electrode V12 of the power supply circuit (11); the cathode of the sixth diode (452) is connected to the pin of the third touch switch (451), and the anode is connected to the negative electrode V12 of the power supply circuit (11).

[0024] The present application provides a device for measuring the contact impedance between an electromyographic multi-channel electrode and a biological body, comprising a control processor circuit, a plurality of multi-way switches, and an electrode interface configured with a multi-way connector; a multi-channel measuring device is set up through the plurality of multi-way switches and the electrode interface configured with a multi-way connector, and according to the instruction sent by the control processor circuit, the excitation output of the measuring circuit (21) is connected to the current loop of the designated channel electrode point of the high-density electrode under the cooperation of the plurality of multi-way switches and the electrode interface configured with a multi-way connector, and a contact impedance value is measured using the path of each electrode point, and the contact status between the body and the electrode is jointly determined by the plurality of contact impedance values, thereby ensuring the reliability of the contact of each channel electrode point, and further improving the success rate of electromyographic signal acquisition. In addition, when the impedance to be measured is small, the compensation circuit (22) can be connected to the measurement loop by configuring the second multi-way switch (32) through the control processor circuit, so as to increase the output driving capability of the first excitation signal T11 output by the measuring circuit (21) and reduce the output impedance, so that the circuit can measure the impedance value within a smaller range to cope with the contact impedance value to be measured in a large range of high-density electromyographic electrodes. In addition, by connecting the input end of the second multi-way switch (32) to the output end connected to the calibration circuit (27), the first excitation signal T11 can be introduced into the calibration circuit, and the internal coefficient of the measurement circuit can be calibrated using the standard resistor (271) with a known impedance value in the calibration circuit and the degree of the measurement circuit (21) when the standard resistor (271) is connected, so that the measurement error is effectively controlled. The above-mentioned multi-channel switching, small impedance compensation measurement, and calibration technology can be flexibly combined under software configuration to realize automatic, high-precision and rapid measurement of multi-channel electrode contact impedance, guide the attachment and installation of high-density electromyography electrodes, and ensure the signal quality of the measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 A circuit logic diagram of a measuring device provided in an embodiment of the present application;

[0027] Figure 2 A circuit logic diagram of a measuring device provided in an embodiment of the present application when performing a first measurement;

[0028] Figure 3 A structural diagram of a control processor provided in an embodiment of the present application;

[0029] Figure 4 A structural diagram of an electrode interface provided in an embodiment of the present application;

[0030] Figure 5 A structural diagram of a grounding interface provided in an embodiment of the present application;

[0031] Figure 6 A structural diagram of a first multi-way switch provided in an embodiment of the present application;

[0032] Figure 7 A structural diagram of a second multi-way switch provided in an embodiment of the present application;

[0033] Figure 8 A structural diagram of a third multi-way switch provided in an embodiment of the present application;

[0034] Fig. 9 A structural diagram of a fourth multi-way switch provided in an embodiment of the present application;

[0035] Fig.10 A structural diagram of a measurement circuit provided in an embodiment of the present application;

[0036] Fig.11 A structural diagram of a power supply circuit provided in an embodiment of the present application;

[0037] Fig.12 A structural diagram of a display circuit provided in an embodiment of the present application;

[0038] Fig.13 A structural diagram of a compensation circuit provided in an embodiment of the present application;

[0039] Fig.14 A structural diagram of a calibration circuit provided in an embodiment of the present application;

[0040] Fig.15 A structural diagram of an alarm circuit provided in an embodiment of the present application;

[0041] Fig.16 A structural diagram of a wireless output circuit provided in an embodiment of the present application;

[0042] Fig.17 A structural diagram of a storage circuit provided in an embodiment of the present application;

[0043] Fig.18 A structural diagram of a first button, a second button, and a third button provided in an embodiment of the present application;

[0044] Fig.19 A schematic diagram of a working circuit of a compensation circuit provided in an embodiment of the present application;

[0045] Fig. 20 A schematic diagram of a working circuit of a calibration circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application is clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work also belong to the scope of protection of the present application. In addition, it should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other in the absence of conflict. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0047] Figure 1 According to an embodiment of the present application, a measuring device for measuring the contact impedance between a multi-channel electrode of a high-density electromyographic signal acquisition device and a biological body is shown. Figure 1 As shown, combined with Figure 2 The device comprises: a control processor circuit (01), a power supply circuit (11), a measurement circuit (21), a first multi-way switch (31), a second multi-way switch (32), a third multi-way switch (35), a fourth multi-way switch (36), an electrode interface (41), and a grounding interface (42).

[0048] The control processor circuit (01) is connected to other circuits and switches;

[0049] The electrode interface (41) is provided with a multi-way connector (411), and the multi-way connector (411) is respectively connected to the first multi-way switch (31), the third multi-way switch (35), and the fourth multi-way switch (36);

[0050] The measuring circuit (21) is also connected to the second multi-way switch (32) and the grounding interface (42) respectively;

[0051] The second multi-way switch (32) is also connected to the first multi-way switch (31);

[0052] The first multi-way switch (31) is also connected to the third multi-way switch (35), the fourth multi-way switch (36), and the electrode interface (41) respectively;

[0053] The third multi-way switch (35) and the fourth multi-way switch (36) are respectively connected to the electrode interface (41).

[0054] The “connection” in this application generally refers to a cable connection unless otherwise specified, and can of course be replaced by other connection methods based on actual conditions.

[0055] Among them, the multi-channel electrode of the high-density EMG signal acquisition device is the electrode on the high-density EMG signal acquisition device, generally including a signal acquisition electrode (hereinafter referred to as "signal electrode") and a ground electrode, wherein the signal acquisition electrode is a flexible electrode containing multiple channel contact points attached to the skin surface above the muscle, and the ground electrode is a single-channel reference electrode attached to the position away from the muscle to be measured and is not affected by the EMG signal. The EMG signal acquisition device collects the EMG signal potential difference between the signal electrode and the ground electrode through the above electrodes to diagnose the health and physiological condition of the organism through the EMG signal.

[0056] The connection between the control processor circuit (01) and other circuits and switches can be understood as follows: the control processor circuit (01) is respectively connected to the power supply circuit (11), the measurement circuit (21), the display circuit (23), the first multi-way switch (31), the second multi-way switch (32), the third multi-way switch (35), the fourth multi-way switch (36), the electrode interface (41), and the ground interface (42).

[0057] Alternatively, see Figure 3 The control processor circuit (01) includes a microprocessor (011) and a 25Mhz crystal oscillator (012); wherein the microprocessor (011) has control software inside, and can be connected with each circuit in the device in a predetermined manner to perform data exchange and control the working state of the circuit; the function of the 25Mhz crystal oscillator (012) is to provide a stable and accurate clock signal to the microprocessor (011).

[0058] Furthermore, the microprocessor (011) may be a micro control unit.

[0059] The organism may be a human or other organisms.

[0060] The multi-way connector (411) is used to connect the multi-channel signal electrodes of the high-density electromyographic signal acquisition device, and is also used to receive the excitation signal for measuring the impedance of the biological body sent by the first multi-way switch (31), the third multi-way switch (35), and the fourth multi-way switch (36).

[0061] Each multi-way connector (411) includes a plurality of channel connection pins, and each channel connection pin can be connected to a connection end of the first multi-way switch (31), the third multi-way switch (35) or the fourth multi-way switch (36), so as to realize multi-way measurement. When one multi-way connector (411) cannot meet the measurement requirements, multiple multi-way connectors (411) can be connected in parallel, or connection ends can be directly added to the current multi-way connector (411) until the measurement requirements are met.

[0062] Alternatively, see Figure 4 , each channel of the multi-way connector (411) is provided with a first diode (412), Figure 4 Taking a multi-way connector (411) configured with a first diode (412) as an example, it is only an exemplary description; the cathode of each of the first diodes (412) is connected to a corresponding pin of the multi-way connector (411), and the anode is connected to the negative electrode V12 terminal of the power supply circuit (11).

[0063] The first diode (412) plays a role in static electricity and surge protection, preventing static electricity and surge voltage received by the multi-way connector (411) from damaging the internal circuit.

[0064] Alternatively, see Figure 5 The grounding interface (42) comprises a grounding socket (421) and a second diode (422); the grounding socket (421) is connected to a grounding electrode; the grounding socket (421) is used to receive an excitation return signal returned by the grounding electrode; the cathode of the second diode (422) is connected to the grounding socket (421), and the anode of the second diode (422) is connected to the negative electrode V12 terminal of the power supply circuit (11).

[0065] The ground electrode is a ground electrode of an electromyographic signal acquisition device. When in use, the skin of the biological body is connected between the signal electrode and the ground electrode.

[0066] The second diode (422) plays a role in static electricity and surge protection, preventing the static electricity and surge voltage received by the grounding socket (421) from damaging the internal circuit.

[0067] The multi-way connector (411) cooperates with the first multi-way switch (31), the second multi-way switch (32), the third multi-way switch (35), and the fourth multi-way switch (36) to realize multi-channel signal transmission. An example is given below to illustrate.

[0068] For example, see Figure 1 , Figure 2 and Figure 7 The second multi-way switch (32) includes a single-pole three-throw switch multiplexer (321); the control processor circuit (01) is connected to the control pin of the single-pole three-throw switch multiplexer (321), and the single-pole three-throw switch multiplexer (321) switches the internal switch according to the signal 0132 sent by the control processor circuit (01), and forwards the received first excitation signal T11 to the input pin of the first multi-way switch (31), or the compensation circuit (22), or the calibration circuit (27).

[0069] See also Figure 1 , Figure 2 and Figure 6 , the first multi-way switch (31) is a single-pole three-throw switch multiplexer (311); the control processor circuit (01) will send a control signal 0131 to the single-pole three-throw switch multiplexer (311), and the single-pole three-throw switch multiplexer (311) will switch the internal switch according to the received control signal 0131, and send the received first excitation signal T11 to the input end of the third multi-way switch (35), the input end of the fourth multi-way switch (36) or a pin of the above-mentioned electrode interface (41);

[0070] See also Figure 1 , Figure 2 and Figure 8 , the third multi-way switch (35) includes a single-pole thirty-two-throw switch multiplexer (351); the single-pole thirty-two-throw switch multiplexer (351) receives a control signal 0135 sent by the control processor circuit (01), and the single-pole thirty-two-throw switch multiplexer (351) switches an internal switch according to the control signal 0135 sent, and forwards the first excitation signal T11 to the path corresponding to the above-mentioned electrode interface (41);

[0071] See also Figure 1 , Figure 2 and Fig. 9 The fourth multi-way switch (36) includes a single-pole thirty-two-throw switch multiplexer (361); the single-pole thirty-two-throw switch multiplexer (361) receives a control signal 0136 sent by the control processor circuit (01), and the single-pole thirty-two-throw switch multiplexer (361) switches the internal switch according to the control signal 0136 sent, and forwards the first excitation signal T11 to the path corresponding to the above-mentioned electrode interface (41).

[0072] As can be seen from the above content, the third multi-way switch (35) includes 32 channels, which can be numbered 1-32, and the fourth multi-way switch (36) includes 32 channels, which can be numbered 33-64. The first multi-way switch (31) can also directly send the first excitation signal T11 to the right leg driving electrode pin of the electrode interface 41. Therefore, there are a total of 65 channels. Correspondingly, 65 channels (including the right leg driving electrode pin) are also set on the electrode interface 41 to connect the 65 channels on the signal electrode. When in use, each channel is switched in turn according to the instructions sent by the control processor circuit (01), so that the contact impedance corresponding to each channel can be obtained.

[0073] In addition, it should be noted that this is only an example description. When the multi-way switch cannot meet the measurement requirements, the number of paths and channels can be increased by increasing the number of first multi-way switches (31), third multi-way switches (35) and fourth multi-way switches (36) to meet the measurement requirements.

[0074] Alternatively, see Figure 2 and Fig.10 The measurement circuit (21) comprises an impedance measurement chip (211), the impedance measurement chip (211) is configured with an impedance measurement circuit and a digital signal processor (English full name: Digital Signal Processing; English abbreviation: DSP) connected to each other; the digital signal processor is connected to the control processor circuit (01), the input of the impedance measurement circuit, that is, the excitation return signal T12 input is connected to the ground interface (42), and the first excitation signal output T11 of the impedance measurement circuit is connected to the second multi-way switch (32). The impedance measurement chip (211) can use AD5933 or other integrated circuits that integrate excitation signal generation function and excitation return signal analysis function, and the impedance measurement chip (211) can also be replaced by a circuit composed of discrete components that provide the same function.

[0075] The control processor circuit (01) exchanges data with the digital signal data processor through a preset communication method. When the digital signal processor receives the control information 0121 sent by the control processor circuit (01), the digital signal processor sends a signal output instruction to the impedance measurement circuit; when the impedance measurement circuit receives the output instruction, the output pin will output a first excitation signal T11 in the form of a sine wave. After the first excitation signal T11 passes through the designated electrode path that is connected by the first multi-way switch (31), the third multi-way switch (35), the fourth multi-way switch (36), and the electrode interface (41), the amplitude attenuation and phase change will occur after passing through the object to be measured, and a first excitation return signal T12 will be generated; the first excitation return signal T12 returns to the input pin of the impedance measurement chip through the ground interface (42), and is transmitted to the DSP through the input pin; the DSP performs a discrete Fourier transform (DFT) on the first excitation return signal T12, and sends the transformed data to the control processor circuit (01) to scan each frequency point, and the internal software of the control processor circuit (01) calculates the measured impedance value.

[0076] The object to be tested is a signal electrode, a biological organism, and a ground electrode which are connected in series in sequence.

[0077] Alternatively, see Fig.11 The power supply circuit (11) includes a lithium-ion battery (111), a battery management chip (112), and a power converter (113); wherein the lithium-ion battery (111) is responsible for supplying power to the entire measuring device and can be repeatedly charged and discharged. The lithium-ion battery (111) has a temperature measurement circuit inside, which sends a temperature signal 1111 inside the lithium-ion battery (111) to the control processor circuit (01) to prevent power supply abnormalities caused by excessive battery temperature; the battery management chip (112) is responsible for detecting the power usage status of the entire measuring device and sending power data 1121 to the control processor circuit The circuit (01) is used for processing; the power converter (113) is a low voltage difference linear regulator, the power converter (113) receives the current output by the lithium ion battery (111), stabilizes the current, outputs a direct current power supply, and then supplies power to the entire circuit through the power supply; the positive electrode V11 of the lithium ion battery (111) is connected to the positive electrode of the power converter (113) and the battery management chip (112), and the negative electrode V12 of the lithium ion battery (111) is first connected to the negative electrode of the power converter (11) and the negative electrode of the measuring device, and then connected to the battery management chip (112).

[0078] Alternatively, see Figure 1 , Figure 2 and Fig.12The measuring device further comprises a display circuit (23), wherein the display circuit (23) comprises a display (231); the display (231) exchanges information with the control processor circuit (01) via a preset communication method, and can display the measurement process, channel coding, impedance value corresponding to the channel, measurement results, power information, storage card information, and wireless connection status.

[0079] Alternatively, see Fig.13 The measuring device further comprises a compensation circuit (22), wherein the compensation circuit (22) comprises an amplifier (221), a first single-pole single-throw switch (222), a first resistor (223), a second resistor (224), a third resistor (225), and a fourth resistor (226); a control pin of the first single-pole single-throw switch (222) is connected to the control processor circuit (01), and a control signal 0133 sent by the control processor circuit (01) can control the opening and closing of the first single-pole single-throw switch (222); one end of the first resistor (223) is connected to a positive power supply electrode V11 output by a power supply circuit (11), The other end of the first resistor (223) is connected to the positive input terminal +IN of the amplifier (221); one end of the second resistor (224) is connected to the positive input terminal +IN of the amplifier (221), and the other end of the second resistor (224) is connected to the negative power supply terminal V12 of the power supply circuit (11); one end of the third resistor (225) is used to receive the first excitation signal T11, and the other end is connected to the reverse input pin -VIN of the amplifier (221); one end of the fourth resistor (226) is connected to the reverse input pin -VIN of the amplifier (221), and the other end is connected to the output pin Vout of the amplifier (221).

[0080] Through the connection, the output pin of the amplifier (221) will send the compensated excitation signal, recorded as the second excitation signal T21, to the input end of the two-way switch multiplexer (222); the above-mentioned control processor circuit (01) will send a control signal 0133 to the first single-pole single-throw switch (222), and the first single-pole single-throw switch (222) switches the internal switch to connect or block the connection between the compensated second excitation signal T21 and the input end of the first multiplexer (31).

[0081] The amplifier (221) is a precision amplifier, and the first resistor (223), the second resistor (224), the third resistor (225), and the fourth resistor (226) are high-precision resistors (with an error less than 0.1%).

[0082] Since the measurement range of the original measurement circuit (21) is limited, when the impedance of the object to be measured is less than the preset value, for example, less than 7 kilo-ohms, the original measurement circuit (21) cannot measure the accurate impedance because the current driving capability of the first excitation signal T11 output by the original measurement circuit (21) is limited and the equivalent output impedance is large. Therefore, after the original measurement circuit (21) is used for measurement, if the impedance is less than the preset value, the first excitation signal T11 output by the measurement circuit (21) is compensated by the compensation circuit (22) to reduce the output impedance, enhance the excitation signal driving capability, and expand the measurement range, and then measure to obtain an accurate small impedance value. The access of the compensation circuit (21) is achieved by configuring the second multi-way switch (32).

[0083] Alternatively, see Fig.14 The measuring device further comprises a calibration circuit (27), wherein the calibration circuit (27) comprises a standard resistor (271) and a second single-pole single-throw switch (272); one end of the standard resistor (271) is connected to the first excitation signal T11, and the other end is connected to one end of the second single-pole single-throw switch (272); the other end of the second single-pole single-throw switch (272) is connected to the excitation return signal input end of the measuring circuit (21); and the second single-pole single-throw switch (272) is also communicatively connected to the control processor circuit (01).

[0084] The standard resistor (271) is used to provide a reference resistance value R for the measuring circuit (21); the single-pole single-throw switch (272) can receive a control signal 0127 sent by the control processor circuit (01), and the single-pole single-throw switch (272) switches an internal switch according to the control signal 0127 to connect and disconnect the standard resistor (271) from the input end of the measuring circuit (21). The internal coefficient of the measuring circuit is calibrated using the known impedance value R in the calibration circuit and the degree of the measuring circuit (21) when the standard resistor (271) is connected, so that the measurement error is effectively controlled.

[0085] The standard resistor (271) is a resistor with a known resistance value, and the resistance value can be determined according to actual conditions, and a high-precision standard resistor (with an error of less than 0.1%) is selected.

[0086] Alternatively, see Fig.15The measuring device further comprises an alarm circuit (24), wherein the alarm circuit (24) comprises a buzzer (241), a third diode (242), and an N-channel MOSFET (243); a gate of the N-channel MOSFET (243) is connected to the control processor circuit (01) to receive a control level signal sent by the control processor circuit (01), a drain of the N-channel MOSFET (243) is connected to a negative electrode of the buzzer (241), and a source of the N-channel MOSFET (243) is connected to a power supply circuit (11) a negative electrode V12 of the alarm circuit (24); one foot of the buzzer (241) is connected to the positive electrode V11 of the power supply circuit (11), and the other foot is connected to the drain of the N-channel MOSFET (243); the buzzer (241) can emit a prompt sound according to the control signal 0124; the cathode of the third diode (242) is connected to the positive electrode of the buzzer (241), and the anode of the third diode (242) is connected to the negative electrode of the buzzer (241), so as to eliminate the peak signal generated when the alarm circuit (24) is working, so as to ensure the normal operation of the alarm circuit (24).

[0087] Alternatively, see Fig.16 The measuring device further comprises a wireless transmission circuit (25), wherein the wireless transmission circuit (25) comprises a wireless module (251), and the wireless module (251) is respectively connected to the control processor circuit (01) and the terminal device client for communication.

[0088] The wireless module (251) is a multi-protocol module that can communicate with the above-mentioned control processor circuit (01) through a preset communication interface. The control processor circuit (01) will send the data information 0125 to the terminal device in real time through the wireless module (251). The terminal device can be a mobile phone or a host computer. Furthermore, a client application corresponding to the measuring device is installed on the terminal device. Through the client application, the user can view the data sent by the control processor circuit 01, and can also use the terminal device to send data information to the control processor circuit (01) through the wireless module (251).

[0089] Alternatively, see Fig.17 The measuring device further comprises a storage circuit (26), wherein the storage circuit (26) comprises a self-popup MicroSD card slot (261) and a memory (262), wherein the self-popup MicroSD card slot (261) is respectively communicatively connected to the memory (262) and the control processor circuit 01.

[0090] The self-ejecting MicroSD card slot (261) can be adapted to a MicroSD (TF card) memory (262); the control processor circuit (01) is connected to the self-ejecting MicroSD card slot (261) through a preset communication method, and the measured impedance data and device status are transferred to the MicroSD (TF card) memory (262) through the self-ejecting MicroSD card slot (261), thereby realizing a local data storage function; the control processor circuit (01) can also be connected to the self-ejecting MicroSD card slot (261) through a preset communication method to read data in the MicroSD (TF card) memory (262).

[0091] Alternatively, see Fig.18 The device further comprises a first button (43), a second button (44), and a third button (45); the first button (43) comprises a first light touch switch (431) and a fourth diode (432), the second button (44) comprises a second light touch switch (441) and a fifth diode (442), and the third button (45) comprises a third light touch switch (451) and a sixth diode (452); the first light touch switch (431), the second light touch switch (441), and the third light touch switch (451) are connected to the control processor circuit (01), and output a control signal when pressed. to the control processor circuit (01), and the control processor circuit (01) will send corresponding signals to control related circuits according to the functions defined by the internal software; the cathode of the fourth diode (432) is connected to the pin of the first touch switch (431), and the anode is connected to the negative electrode V12 of the power supply circuit (11); the cathode of the fifth diode (442) is connected to the pin of the second touch switch (441), and the anode is connected to the negative electrode V12 of the power supply circuit (11); the cathode of the sixth diode (452) is connected to the pin of the third touch switch (451), and the anode is connected to the negative electrode V12 of the power supply circuit (11).

[0092] Among them, the fourth diode (432), the fifth diode (442), and the sixth diode (452) play a role in static electricity and surge protection, preventing static electricity and surge voltage from damaging the internal circuit when the first touch switch (431), the second touch switch (441), and the third touch switch (451) are used.

[0093] When you need to measure whether the connection between the electrode of the electromyographic signal acquisition device and the body meets the requirements, you can first perform a preliminary impedance value measurement, see Figure 2 , the preliminary impedance value measurement process is as follows:

[0094] The second button (44) is pressed down for 5 seconds, and the control processor circuit (01) performs a self-test on the measuring circuit. After the self-test passes, "under test" will be displayed on the display circuit (23). The second button (44) is pressed again, and the device starts to measure the impedance value of the object to be tested.

[0095] After the control processor circuit (01) receives the test start instruction 4401 issued by the second button (44), the control processor circuit (01) sends an instruction signal (0121) to the measurement circuit (21) to trigger the measurement. The measurement circuit (21) sends a sine wave, that is, a first excitation signal T11 to the input end of the second multi-way switch (32). The control processor circuit (01) sends a second multi-way switch (32) switching instruction 0132. The first excitation signal T11 reaches the input end of the first multi-way switch (31) through the second multi-way switch (32). The control processor circuit (01) will send a first multi-way switch (31) switching instruction 0131. The first excitation signal T11 reaches the input end of the third multi-way switch (35) or the input end of the fourth multi-way switch (36) through the first multi-way switch (31), or directly reaches the right leg driving electrode pin of the electrode interface (41). The first multi-way switch (31), the third multi-way switch (35) and the fourth multi-way switch (36) are switched one by one in the order preset by the switching instruction, and the first excitation signal T11 is sequentially transferred to the electrode point in each channel No. 1-65 of the electrode interface (41), thereby realizing multi-channel measurement and improving the accuracy of measurement. When the electrode is in close contact with the skin, the contact impedance of the electrode-skin contact interface is relatively small. At the same time, the impedance of normal human skin tissue is relatively small at the high frequency of the first excitation signal T11. Therefore, the overall impedance of the object to be measured is relatively small. The first excitation signal T11 will attenuate when passing through the skin tissue, thereby generating a first excitation return signal T12. The first excitation return signal T12 will be connected to the ground interface (42) through a grounding electrode (for example, the grounding electrode can be a bracelet electrode worn on the skin or a conventional Ag / AgCl gel electrode), and then the first excitation return signal T12 will be sent to the input pin of the measurement circuit (21) through the grounding interface (42). After the measurement circuit (21) receives the first excitation return signal T12, its internal DSP will perform discrete Fourier processing on the first excitation return signal T12. The measurement circuit (21) sends the measurement result data to the control processor circuit (01) for processing, thereby completing the preliminary impedance value measurement.

[0096] In the above measurement process, the compensation circuit (22) and the calibration circuit (27) are disconnected by the second multi-way switch (32) and do not participate in this measurement. The output end of the compensation circuit (22) is disconnected by the first single-pole single-throw switch (222) inside the compensation circuit (22).

[0097] When the initial measurement is completed, if the impedance of some channels is less than the preset value, the first excitation signal T11 output by the measuring circuit (21) is compensated by the compensation circuit (22) to expand the measurement range, and then the measurement is performed to obtain the accurate value of the contact impedance under the condition of small resistance. Optionally, see Fig.19 , the small impedance measurement process is as follows:

[0098] After the control processor circuit (01) completes the preliminary resistance value acquisition, it will perform calculation and processing based on the measured impedance value data. When the small impedance value measurement accuracy is insufficient (for example, the initially measured impedance is less than the preset value of 5K ohms or 7K ohms, etc.), the control processor circuit (01) will send a channel switching signal (0132) to allow the second multi-way switch (32) to transfer the sinusoidal first excitation signal T11 to the compensation circuit (22). The first excitation signal T11 is amplified by the compensation circuit (22) and the compensated second excitation signal T21 is sent to the input of the first single-pole single-throw switch (222). The control processor circuit (01) sends a channel switching signal 0133 to turn on the first single-pole single-throw switch (222) inside the compensation circuit (22), and the compensated second excitation signal T21 passes through the first single-pole single-throw switch (222) and is sent to the input end of the first multi-way switch (31). The control processor circuit (01) sends a first multi-way switch (31) switching instruction 0131, and the second excitation signal T21 is connected to the third multi-way switch (35) input end, or the fourth multi-way switch (36) input end, or the right leg driving electrode pin of the electrode interface (41) through the first multi-way switch (31). The signal return process of the returned second excitation return signal T22 is the same as that of the first excitation return signal T12, and is not repeated here.

[0099] When measuring low impedance, the calibration circuit (27) will receive a switching control signal (0127) sent by the control processor circuit (01), causing the second single-pole single-throw switch (272) in the calibration circuit (27) to be disconnected internally, and the calibration circuit (27) will not participate in the operation.

[0100] The second multi-way switch (32) has a single-pole three-throw switch multiplexer (321) inside. When the output of the second multi-way switch (32) is switched to the compensation circuit (22), the other outputs are disconnected from the input ends, so the signal path from the second multi-way switch (32) to the first multi-way switch (31) is disconnected.

[0101] After the control processor circuit (01) completes the measurement of the small impedance value, it will calculate and process again according to the measured impedance value data, and save all the data.

[0102] Combined with the preliminary measurement and small resistance measurement results, the final measurement result will be displayed through the display circuit (23), and the measured resistance value of each channel will be displayed line by line. The display page can be switched by short pressing the third button (45) and the first button (43).

[0103] When the measurement accuracy is insufficient, calibration can be performed by the calibration circuit 27. Fig. 20 , the calibration process is as follows:

[0104] When the measurement value is not accurate enough, the internal calibration instruction can be triggered by pressing the button (45) for a long time, and the control processor circuit (01) will send a channel switching signal (0132) to allow the second multi-way switch (32) to transfer the first excitation signal T11 to the calibration circuit (27). The control processor circuit (01) will send a channel switching signal (0127) to connect the input and output ends of the second single-pole single-throw switch (272) inside the calibration circuit (27), and the standard resistor (271) in the calibration circuit (27) is connected to the input end of the measurement circuit (21), triggering the measurement of the standard resistor (271) and using the measured value as the standard corresponding impedance value. The control processor circuit (01) recalculates the calibration coefficient inside the measurement software according to the standard impedance corresponding measurement value and records it for subsequent measurement.

[0105] Exemplarily, the measurement process is described by taking the objects to be measured as a signal electrode, a human body, and a ground electrode as an example.

[0106] Install the signal electrode and ground electrode:

[0107] One end of the signal electrode is fixedly connected to the skin to ensure that each metal point of the signal electrode is in close contact with the skin, and the other end of the signal electrode is inserted into the electrode interface (41) of the measuring device;

[0108] The plug of the grounding electrode is inserted into the grounding interface (42) of the measuring device, and the other end of the grounding electrode is in contact with the skin using a grounding bracelet or a gel electrode.

[0109] Power-on test:

[0110] Press the second button (44) for 5 seconds and then release it. The measuring device will start and perform a self-check. After about 3 seconds, the prompt "Device is normal" will be displayed on the display 231, indicating that the measuring device can be used to measure impedance. If three consecutive short "beep beep" sounds are emitted, it means that the detection is abnormal and the measuring device cannot be used.

[0111] Press the second button (44) and release it immediately, the device starts testing, and after about 3 seconds a 1 second long "beep" sound can be heard, indicating the end of the test.

[0112] Data shows:

[0113] After the test, the number of channels and contact impedance value can be shown on the display; it should be noted that the displayed contact impedance value is an accurate value after combining the above preliminary impedance measurement and small impedance measurement results.

[0114] When the number of electrodes is too large, the first button (43) can be pressed down and released immediately to turn the page down;

[0115] Press the third button (45) down and release it immediately to turn the page up and view the test results on the measuring device end;

[0116] Long pressing the third button (45) can trigger the internal calibration function, and after calibration, the second button (44) needs to be short pressed again to re-trigger the measurement.

[0117] Data transfer:

[0118] Method 1: Connect to the terminal device through the wireless function, such as a mobile phone APP or a PC client, to back up data;

[0119] Method 2: Remove the TF memory card from the SD card slot, insert it into a computer or adapter, and copy, cut, and back up the measurement data.

[0120] In addition, it should be noted that the scope of this application includes feasible technical solutions formed by specific combinations of the above-mentioned technical features, and should also cover other feasible technical solutions formed by any combination of the above-mentioned technical features or their equivalent features without departing from the above-mentioned application concept.

[0121] Finally, it should be noted that all contents not described in the technical solution of this application can be implemented using existing technologies. In addition, the above embodiments are only used to illustrate the technical solution of this application, rather than to limit it; although the application is described in detail with reference to the above embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the above embodiments, or replace some or all of the technical features therein with equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A device for measuring contact impedance between an electromyographic multi-channel electrode and a biological organism, characterized in that: include: A control processor circuit (01), a power supply circuit (11), a measurement circuit (21), a first multi-way switch (31), a second multi-way switch (32), a third multi-way switch (35), a fourth multi-way switch (36), an electrode interface (41), and a ground interface (42); The control processor circuit (01) is connected to other circuits and switches; The electrode interface (41) is provided with a multi-way connector (411), and the multi-way connector (411) is respectively connected to the output ends of the first multi-way switch (31), the third multi-way switch (35), and the fourth multi-way switch (36); The output end of the measuring circuit (21) is also connected to the second multi-way switch (32), and the input end is also connected to the ground interface (42); The output end of the second multi-way switch (32) is also connected to the first multi-way switch (31); The output end of the first multi-way switch (31) is also respectively connected to the third multi-way switch (35), the fourth multi-way switch (36), and the electrode interface (41); The third multi-way switch (35) and the fourth multi-way switch (36) are respectively connected to the electrode interface (41); The measuring device further comprises a compensation circuit (22), the compensation circuit (22) comprising an amplifier (221), a first single-pole single-throw switch (222), a first resistor (223), a second resistor (224), a third resistor (225), and a fourth resistor (226); a control pin of the first single-pole single-throw switch (222) is connected to the control processor circuit (01), and a control signal (0133) issued by the control processor circuit (01) can control the opening and closing of the first single-pole single-throw switch (222); one end of the first resistor (223) is connected to The positive power electrode V11 output by the power circuit (11) and the other end of the first resistor (223) are connected to the positive input terminal +VIN of the amplifier (221); one end of the second resistor (224) is connected to the positive input terminal +VIN of the amplifier (221), and the other end of the second resistor (224) is connected to the negative power electrode V12 of the power circuit (11); one end of the third resistor (225) is connected to an output terminal of the second multi-way switch (32) for receiving the first excitation signal T11, and the other end is connected to the negative input terminal -VIN of the amplifier (221); One end of the fourth resistor (226) is connected to the inverting input terminal -VIN of the amplifier (221), and the other end is connected to the output pin Vout of the amplifier (221) and the input terminal of the first multi-way switch (31).

2. The measuring device according to claim 1, characterized in that The measuring device further comprises a calibration circuit (27), wherein the calibration circuit (27) comprises a standard resistor (271) and a second single-pole single-throw switch (272); one end of the standard resistor (271) is connected to one end of the second single-pole single-throw switch (272), the other end of the standard resistor (271) is connected to an output pin of the second multi-way switch (32), the other end of the second single-pole single-throw switch (272) is connected to the measuring circuit (21), and the second single-pole single-throw switch (272) is also communicatively connected to the control processor circuit (01).

3. The measuring device according to claim 2, characterized in that The measuring device further comprises an alarm circuit (24), wherein the alarm circuit (24) comprises a buzzer (241), a third diode (242), and an N-channel MOSFET (243); the gate of the N-channel MOSFET (243) is communicatively connected to the control processor circuit (01), the drain of the N-channel MOSFET (243) is connected to the negative electrode of the buzzer (241), and the source of the N-channel MOSFET (243) is connected to the negative electrode V12 of the power supply circuit (11); the positive electrode of the buzzer (241) is connected to the positive electrode V11 of the power supply circuit (11), and the negative electrode is connected to the drain of the N-channel MOSFET (243); the cathode of the third diode (242) is connected to the positive electrode of the buzzer (241), and the anode of the third diode (242) is connected to the negative electrode of the buzzer (241).

4. The measuring device according to claim 2, characterized in that The grounding interface (42) comprises a grounding socket (421) and a second diode (422); the grounding socket (421) is connected to a grounding electrode; the grounding socket (421) is used to receive a first excitation return signal T12 returned by the grounding electrode; the cathode of the second diode (422) is connected to the grounding socket (421), and the anode of the second diode (422) is connected to a negative electrode V12 terminal of a power supply circuit (11).

5. The measuring device according to claim 1, characterized in that Each channel of the multi-way connector (411) is provided with a first diode (412); the cathode of each first diode (412) is connected to a corresponding pin of the multi-way connector (411), and the anode is connected to the negative electrode V12 terminal of the power supply circuit (11).

6. The measuring device according to claim 1, characterized in that The measurement circuit (21) comprises an impedance measurement chip (211), wherein the impedance measurement chip (211) is provided with an impedance measurement circuit and a digital signal processor which are connected to each other; the digital signal processor is connected to the control processor circuit (01), and the impedance measurement circuit is respectively connected to the second multi-way switch (32) and the ground interface (42).

7. The measuring device according to claim 2, characterized in that The measuring device further comprises a wireless transmission circuit (25), wherein the wireless transmission circuit (25) comprises a wireless module (251), and the wireless module (251) is communicatively connected to the control processor circuit (01) and the terminal device respectively.

8. The measuring device according to claim 2, characterized in that The measuring device further comprises a storage circuit (26), wherein the storage circuit (26) comprises a self-ejecting MicroSD card slot (261) and a memory (262), wherein the self-ejecting MicroSD card slot (261) is communicatively connected to the memory (262) and the control processor circuit (01), respectively.

9. The measuring device according to any one of claims 1 to 8, characterized in that: The device further comprises a first button (43), a second button (44), and a third button (45); the first button (43) comprises a first light touch switch (431) and a fourth diode (432); the second button (44) comprises a second light touch switch (441) and a fifth diode (442); the third button (45) comprises a third light touch switch (451) and a sixth diode (452); the first light touch switch (431), the second light touch switch (441), and the third light touch switch (452) 1) is connected to the control processor circuit (01); the cathode of the fourth diode (432) is connected to the pin of the first touch switch (431), and the anode is connected to the negative electrode V12 of the power supply circuit (11); the cathode of the fifth diode (442) is connected to the pin of the second touch switch (441), and the anode is connected to the negative electrode V12 of the power supply circuit (11); the cathode of the sixth diode (452) is connected to the pin of the third touch switch (451), and the anode is connected to the negative electrode V12 of the power supply circuit (11).

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