A myoelectric signal acquisition electrode plate falling detection circuit

Abstract

The application relates to the technical field of medical devices and discloses a falling detection circuit of an electromyographic signal collection electrode plate, which comprises a comparison circuit, a voltage regulation circuit, a reference voltage source and an MCU. The collection electrode plate comprises a first electrode plate and a second electrode plate, the first electrode plate and the second electrode plate are in contact with a human body and are used for collecting electromyographic signals, the electromyographic signals and the output of the voltage regulation circuit are jointly connected to the first end of the comparison circuit, the comparison circuit compares the electromyographic signals processed through the voltage regulation circuit with the reference voltage generated by the reference voltage source, generates a signal as a judgment result when the first electrode plate and the second electrode plate are normally connected with the human body, generates another signal as a judgment result when the first electrode plate or the second electrode plate falls off, and sends the judgment result to the MCU, so that the MCU can identify whether the electrode plate falls off through the change of the signal.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to a falling detection circuit of an electromyography signal acquisition electrode plate. BACKGROUND

[0002] Electromyography (EMG) is the superposition of motor unit action potentials (MUAP) in time and space in a large number of muscle fibers. Surface electromyography (SEMG) is the comprehensive effect of superficial muscle EMG and electrical activity on the skin surface of the nerve trunk, which can reflect the activity of the neuromuscular system to a certain extent. SEMG has the advantages of non-invasiveness, non-invasiveness, and simple operation in measurement. Therefore, SEMG has important practical value in clinical medicine, human-machine ergonomics, rehabilitation medicine, and sports science.

[0003] In specific implementation, the device collects SEMG in the way that the electrode plate contacts the human body for analysis and evaluation, and the falling of the electrode plate will cause the loss and inaccuracy of SEMG collection.

[0004] Therefore, how to detect the falling of the electromyography signal acquisition electrode plate is a problem to be solved by those skilled in the art. SUMMARY

[0005] The purpose of the present application is to provide a falling detection circuit of an electromyography signal acquisition electrode plate for detecting the falling of the electromyography signal acquisition electrode plate.

[0006] To solve the above technical problems, the present application provides a falling detection circuit of an electromyography signal acquisition electrode plate, which comprises:

[0007] a comparison circuit, a voltage regulation circuit, a reference voltage source, and an MCU;

[0008] The output end of the voltage regulation circuit and the first electrode plate are jointly connected to the first end of the comparison circuit, for transmitting the processed electromyography signal collected by the first electrode plate to the comparison circuit for comparison;

[0009] The output end of the voltage regulation circuit and the second electrode plate are jointly connected to the second end of the comparison circuit, for transmitting the processed electromyography signal collected by the second electrode plate to the comparison circuit for comparison;

[0010] The output end of the reference voltage source is connected to the third end and the fourth end of the comparison circuit, for providing a reference voltage for the comparison circuit;

[0011] The MCU is connected to the output end of the comparison circuit, for obtaining the comparison result of the comparison circuit and determining the falling state of the electrode plate according to the comparison result.

[0012] Preferably, the first isolation circuit and the second isolation circuit are further included;

[0013] The output end of the voltage regulating circuit and the first electrode plate are connected with the first end of the comparison circuit through the first isolation circuit;

[0014] The output end of the voltage regulating circuit and the second electrode plate are connected with the second end of the comparison circuit through the second isolation circuit.

[0015] Preferably, the voltage regulating circuit comprises:

[0016] The first resistor and the second resistor;

[0017] The first end of the first resistor and the first end of the second resistor are connected, and are connected with the first isolation circuit and the second isolation circuit as the output end of the voltage regulating circuit; the second end of the first resistor is connected with a power supply, and the second end of the second resistor is grounded.

[0018] Preferably, the first isolation circuit comprises:

[0019] The first operational amplifier and the first capacitor;

[0020] The non-inverting input end of the first operational amplifier is connected with the output end of the voltage regulating circuit, the first electrode plate and the first end of the first capacitor;

[0021] The output end of the first operational amplifier is connected with the inverting input end of the first operational amplifier and the first end of the comparison circuit;

[0022] The second end of the first capacitor is grounded;

[0023] The second isolation circuit comprises: a second operational amplifier and a second capacitor;

[0024] The non-inverting input end of the second operational amplifier is connected with the output end of the voltage regulating circuit, the second electrode plate and the first end of the second capacitor;

[0025] The output end of the second operational amplifier is connected with the inverting input end of the second operational amplifier and the second end of the comparison circuit;

[0026] The second end of the second capacitor is grounded.

[0027] Preferably, the comparison circuit comprises:

[0028] The third operational amplifier, the fourth operational amplifier, the third resistor, the fourth resistor, the fifth resistor and the sixth resistor;

[0029] The first end of the third resistor is connected to the output end of the first operational amplifier as the first end of the comparison circuit, and the second end of the third resistor is connected to the non-inverting input end of the third operational amplifier;

[0030] The first end of the fourth resistor is connected to the output end of the second operational amplifier as the second end of the comparison circuit, and the second end of the fourth resistor is connected to the non-inverting input end of the fourth operational amplifier;

[0031] The inverting input end of the third operational amplifier is connected to the output end of the reference voltage source as the third end of the comparison circuit, and the inverting input end of the fourth operational amplifier is connected to the output end of the reference voltage source as the fourth end of the comparison circuit;

[0032] The first end of the fifth resistor is connected to a power supply, the second end of the fifth resistor is connected to the output end of the third operational amplifier and the first end of the sixth resistor, the second end of the sixth resistor is connected to the output end of the fourth operational amplifier, and the output end of the comparison circuit is connected to the MCU.

[0033] Preferably, the reference voltage source comprises:

[0034] A seventh resistor, an eighth resistor, and a third capacitor;

[0035] The first end of the seventh resistor is connected to a power supply, the first end of the eighth resistor and the first end of the third capacitor are connected to ground, and the second end of the seventh resistor, the second end of the eighth resistor, and the second end of the third capacitor are connected to the inverting input end of the third operational amplifier and the inverting input end of the fourth operational amplifier as the output end of the reference voltage source.

[0036] Preferably, it further comprises a ninth resistor, a tenth resistor, a fourth capacitor, and a fifth capacitor;

[0037] The first end of the ninth resistor and the first end of the fourth capacitor are connected to the output end of the voltage regulation circuit, the second end of the fourth capacitor is connected to ground, and the second end of the ninth resistor is connected to the non-inverting input end of the first operational amplifier;

[0038] The first end of the tenth resistor and the first end of the fifth capacitor are connected to the output end of the voltage regulation circuit, the second end of the fifth capacitor is connected to ground, and the second end of the tenth resistor is connected to the non-inverting input end of the second operational amplifier.

[0039] Preferably, it further comprises an eleventh resistor, a first zener diode, and a second zener diode;

[0040] The anode of the first voltage stabilizing diode is connected to the output end of the comparison circuit, the cathode of the first voltage stabilizing diode, the first end of the eleventh resistor and the cathode of the second voltage stabilizing diode are collectively connected to the MCU, and the second end of the eleventh resistor and the anode of the second voltage stabilizing diode are grounded.

[0041] Preferably, the application further comprises a filter circuit.

[0042] The filter circuit is connected to a power supply and the power supply ends of the first operational amplifier, the second operational amplifier, the third operational amplifier and the fourth operational amplifier.

[0043] Preferably, the application further comprises:

[0044] An alarm device.

[0045] The alarm device is connected to the MCU.

[0046] The falling detection circuit of the myoelectric signal acquisition electrode plate provided by the application comprises a comparison circuit, a voltage regulating circuit, a reference voltage source and an MCU. The acquisition electrode plate comprises a first electrode plate and a second electrode plate, the first electrode plate and the second electrode plate are in contact with a human body and are used for acquiring myoelectric signals, the myoelectric signals and the output of the voltage regulating circuit are collectively connected to the first end of the comparison circuit, the comparison circuit compares the myoelectric signals processed by the voltage regulating circuit with the reference voltage generated by the reference voltage source, generates a signal as a judgment result when the first electrode plate and the second electrode plate are normally connected to the human body, generates another signal as a judgment result when the first electrode plate or the second electrode plate falls off, and sends the judgment result to the MCU, so that the MCU can recognize whether the electrode plate falls off through the change of the signal. BRIEF DESCRIPTION OF DRAWINGS

[0047] In order to more clearly illustrate the embodiments of the application, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0048] Figure 1 The structural diagram of the falling detection circuit of the myoelectric signal acquisition electrode plate provided by the application;

[0049] Figure 2 The circuit diagram of the falling detection circuit of the myoelectric signal acquisition electrode plate provided by the application;

[0050] The reference signs are as follows: 1 is a first electrode plate, 2 is a second electrode plate, 3 is a voltage regulating circuit, 4 is a comparison circuit, 5 is a reference voltage source, and 6 is an MCU. DETAILED DESCRIPTION

[0051] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present invention.

[0052] Electromyography (EMG) signals are the temporal and spatial superposition of motor unit action potentials (MUAPs) from numerous muscle fibers. Surface electromyography (SEMG) signals are the combined effect of superficial muscle EMG and electrical activity on nerve trunks on the skin surface, reflecting neuromuscular activity to a certain extent. SEMG has advantages in measurement such as being non-invasive, non-traumatic, and simple to operate. Therefore, SEMG has important practical value in clinical medicine, ergonomics, rehabilitation medicine, and sports science.

[0053] In practice, the device collects SEMG by having the electrode plates contact the human body for analysis and evaluation. However, the detachment of the electrode plates can lead to missing or inaccurate SEMG collection.

[0054] The core of this invention is to provide a detection circuit for the detachment of electromyography (EMG) signal acquisition plates, which is used to detect the detachment of EMG signal acquisition plates.

[0055] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0056] Figure 1 This is a structural diagram of a circuit for detecting the detachment of an electromyography (EMG) signal acquisition electrode plate, as provided in an embodiment of this application. Figure 1 As shown, the circuit includes:

[0057] 4. Comparator circuit; 3. Voltage regulation circuit; 5. Reference voltage source; 6. MCU;

[0058] The output terminal of the voltage regulation circuit 3 and the first electrode plate 1 are connected to the first terminal of the comparison circuit 4, which is used to process the electromyographic signals collected by the first electrode plate 1 and transmit them to the comparison circuit 4 for comparison.

[0059] The output terminal of the voltage regulation circuit 3 and the second electrode plate 2 are connected together to the second terminal of the comparison circuit 4, which is used to process the electromyographic signals collected by the second electrode plate 2 and transmit them to the comparison circuit 4 for comparison.

[0060] The output terminal of the reference voltage source 5 is connected to the third and fourth terminals of the comparator circuit 4 to provide a reference voltage for the comparator circuit 4.

[0061] The MCU 6 is connected to the output end of the comparison circuit 4, and is used to obtain the comparison result of the comparison circuit 4 and determine the falling state of the electrode plate according to the comparison result.

[0062] It should be noted that the surface electromyogram is an electrical signal accompanied by muscle contraction, and is an important method for non-invasive detection of muscle activity on the body surface. The electromyogram collected by the electrode plate is usually weak. According to the knowledge of neurophysiology, the muscle action potential will generate a potential difference of-90mV to 30mV. Since the human body is a poor conductor of electricity (1MΩ order resistance), only about 1mV peak value can be obtained from the first electrode plate 1 and the second electrode plate 2 on the body surface. It can be understood that the too small electromyogram is not conducive to the comparison of the subsequent comparison circuit 4, and reduces the detection accuracy of the electrode plate falling. Therefore, the voltage adjusting circuit 3 in the embodiment is used to adjust the electromyogram, so as to increase the difference between the electromyogram and the reference voltage, so as to accurately identify the difference of the comparison result when the electrode plate falls, and improve the detection accuracy of the electrode plate falling. The reference voltage provided by the reference voltage source 5 in the embodiment is used to compare with the adjusted electromyogram, so the specific reference voltage value should be related to the voltage adjusted by the voltage adjusting circuit 3.

[0063] The MCU 6 in the embodiment is used to obtain the comparison result of the comparison circuit 4, and determine the falling state of the electrode plate according to the comparison result. In a specific implementation, the MCU 6 can be connected with an alarm device, such as an indicator light buzzer, etc., which can control the alarm device to work when the electrode plate is determined to fall, so as to realize the alarm of the electrode plate falling. The MCU 6 can also be connected with a display device, and the comparison result can be displayed through the display device.

[0064] The falling detection circuit of the electromyogram collection electrode plate provided by the embodiment of the application includes a comparison circuit, a voltage adjusting circuit, a reference voltage source and an MCU. The collection electrode plate includes a first electrode plate and a second electrode plate, the first electrode plate and the second electrode plate are in contact with the human body, and are used to collect electromyograms. The electromyogram and the output of the voltage adjusting circuit are jointly connected to the first end of the comparison circuit, the comparison circuit compares the electromyogram processed by the voltage adjusting circuit with the reference voltage generated by the reference voltage source, generates a signal as a judgment result when the first electrode plate and the second electrode plate are normally connected with the human body, generates another signal as a judgment result when the first electrode plate or the second electrode plate falls, and sends the judgment result to the MCU, so that the MCU can recognize whether the electrode plate falls through the change of the signal.

[0065] It can be understood that the surface electromyogram is very weak and is easily disturbed, and the introduction of electrical elements will affect the falling detection of the electrode plate. Therefore, in the embodiment, first isolation circuit and second isolation circuit are further included.

[0066] The output end of the voltage regulating circuit 3 and the first electrode plate 1 are connected with the first end of the comparison circuit 4 through the first isolation circuit;

[0067] The output end of the voltage regulating circuit 3 and the second electrode plate 2 are connected with the second end of the comparison circuit 4 through the second isolation circuit.

[0068] The isolation circuit in the embodiment includes the first isolation circuit and the second isolation circuit, which are connected with the first electrode plate and the second electrode plate respectively. If the comparison circuit is directly added to the collection signal end, the performance index of the collection channel will be affected. The isolation circuit plays the purpose of signal isolation transmission. In the specific implementation, the isolation circuit can use an operational amplifier, or a transformer, an optical coupler, etc.

[0069] The embodiment also provides a specific voltage regulating circuit 3, Figure 2 A circuit diagram of a falling detection circuit of an electromyographic signal collection electrode plate provided by the embodiment of the application is shown in FIG. 1. Figure 2 As shown in FIG. 1, the voltage regulating circuit 3 includes:

[0070] a first resistor R1 and a second resistor R2;

[0071] The first end of the first resistor R1 and the first end of the second resistor R2 are connected, and are connected with the first isolation circuit and the second isolation circuit as the output end of the voltage regulating circuit 3; the second end of the first resistor R1 is connected with a power supply, and the second end of the second resistor R2 is grounded.

[0072] In the voltage regulating circuit 3, the first resistor R1 and the second resistor R2 are connected with the power supply as voltage dividing resistors, and the connection point of the first resistor R1 and the second resistor R2 is connected with the electromyographic signal and the isolation circuit.

[0073] The embodiment also provides a specific isolation circuit, as shown in FIG. 2, the first isolation circuit includes: Figure 2

[0074] a first operational amplifier X1 and a first capacitor C1;

[0075] The non-inverting input end of the first operational amplifier X1 is connected with the output end of the voltage regulating circuit 3, the first electrode plate 1 and the first end of the first capacitor C1;

[0076] The output end of the first operational amplifier X1 is connected with the inverting input end of the first operational amplifier X1 and the first end of the comparison circuit 4;

[0077] The second end of the first capacitor C1 is grounded;

[0078] The second isolation circuit includes a second operational amplifier X2 and a second capacitor C2;

[0079] ​The non-inverting input of the second operational amplifier X2 is connected to the output of the voltage regulation circuit 3, the second plate 2, and the first terminal of the second capacitor C2;

[0080] The output terminal of the second operational amplifier X2 is connected to the inverting input terminal of the second operational amplifier X2 and the second terminal of the comparator circuit 4;

[0081] The second terminal of the second capacitor C2 is grounded.

[0082] In this embodiment, an operational amplifier is used as a voltage follower to provide signal isolation. As is well known, voltage followers buffer, isolate, and improve load capacity. The output voltage of a voltage isolator approximates the input voltage amplitude and presents a high impedance to the preceding stage circuit and a low impedance to the following stage circuit, thus providing "isolation" between the two stages. The high input impedance and low output impedance of a voltage follower can be understood to an extreme: when the input impedance is very high, it's equivalent to an open circuit to the preceding stage circuit; when the output impedance is very low, it's equivalent to a constant voltage source to the following stage circuit, meaning the output voltage is unaffected by the impedance of the following stage circuit. A circuit that is essentially an open circuit to the preceding stage circuit and whose output voltage is unaffected by the impedance of the following stage circuit naturally provides isolation, preventing interference between the preceding and following stages. The first capacitor C1 and the second capacitor C2 serve as filters.

[0083] This embodiment also provides a specific reference voltage source 5, such as... Figure 2 As shown, the reference voltage source 5 includes:

[0084] Seventh resistor R7, eighth resistor R8, third capacitor C3;

[0085] The first end of the seventh resistor R7 is connected to the power supply. The first end of the eighth resistor R8 and the first end of the third capacitor C3 are grounded together. The second ends of the seventh resistor R7, the eighth resistor R8, and the third capacitor C3 are used together as the output of the reference voltage source 5, which is connected to the inverting input of the third operational amplifier X3 and the inverting input of the fourth operational amplifier X4.

[0086] It should be noted that the electromyographic signal is a voltage close to 0V. In this preferred embodiment, the power supply connected to the first resistor R1 is negative, and correspondingly, the reference voltage generated by the subsequent reference voltage source 5 is also negative. Based on the virtual short and virtual open characteristics of the operational amplifier, the output voltage of the operational amplifier is the corresponding electromyographic signal plus the voltage at the connection point of the first resistor R1 and the second resistor R2. When the electrode plate detaches, the voltage entering the comparator circuit 4 is 0V, which is greater than the negative value of the reference voltage, therefore the output signal is high. When the electrode plate is normally connected, the voltage entering the comparator circuit 4 is a negative value less than the reference voltage, therefore the output signal of the comparator circuit 4 is low. Thus, the MCU6 can determine whether the electrode plate has detached based on the different signals.

[0087] The electromyography (EMG) signal acquisition electrode detachment detection circuit provided in this embodiment uses an operational amplifier as an isolation circuit to achieve signal isolation between the EMG signal acquisition end and the comparison circuit.

[0088] This embodiment also provides a specific comparison circuit 4, such as Figure 2 As shown, the comparator circuit 4 includes:

[0089] Third operational amplifier X3, fourth operational amplifier X4, third resistor R3, fourth resistor R4, fifth resistor R5, sixth resistor R6;

[0090] The first end of the third resistor R3 is connected to the output of the first operational amplifier X1 as the first end of the comparator circuit 4, and the second end of the third resistor R3 is connected to the non-inverting input of the third operational amplifier X3.

[0091] The first end of the fourth resistor R4 is connected to the output of the second operational amplifier X2 as the second end of the comparator circuit 4, and the second end of the fourth resistor R4 is connected to the non-inverting input of the fourth operational amplifier X4.

[0092] The inverting input terminal of the third operational amplifier X3 serves as the third terminal of the comparator circuit 4, and the inverting input terminal of the fourth operational amplifier X4 serves as the fourth terminal of the comparator circuit 4. Both are connected to the output terminal of the reference voltage source 5.

[0093] The first end of the fifth resistor R5 is connected to the power supply. The second end of the fifth resistor R5 is connected to the output of the third operational amplifier X3 and the first end of the sixth resistor R6. The second end of the sixth resistor R6 is connected to the output of the fourth operational amplifier X4. Together, they serve as the output of the comparator circuit 4 and are connected to the MCU6.

[0094] In this embodiment, the third resistor R3 and the fourth resistor R4 are used as matching resistors to connect the operational amplifier in the isolation circuit and the operational amplifier in the comparator circuit 4. The fifth resistor R5 and the sixth resistor R6 are used as pull-up resistors to improve the output high level value. The resistance value of the sixth resistor R6 can be 0V, or it can be omitted in other embodiments.

[0095] The electromyography signal acquisition electrode plate detachment detection circuit provided in this embodiment includes a comparison circuit comprising a third operational amplifier and a fourth operational amplifier. When either the first electrode plate or the second electrode plate detaches, the output signal is changed, thereby enabling the MCU to determine whether the electrode plate has detached.

[0096] In practice, static electricity exists on the surface of human skin. When the electrode plate first contacts the skin, this static electricity can damage the components in the electromyography signal acquisition electrode plate detachment detection circuit. Therefore, as... Figure 2As shown, the embodiment further includes: a ninth resistor R9, a tenth resistor R10, a fourth capacitor C4, and a fifth capacitor C5.

[0097] The first end of the ninth resistor R9 and the first end of the fourth capacitor C4 are commonly connected to the output end of the voltage regulating circuit 3, the second end of the fourth capacitor C4 is grounded, and the second end of the ninth resistor R9 is connected to the non-inverting input end of the first operational amplifier X1.

[0098] The first end of the tenth resistor R10 and the first end of the fifth capacitor C5 are commonly connected to the output end of the voltage regulating circuit 3, the second end of the fifth capacitor C5 is grounded, and the second end of the tenth resistor R10 is connected to the non-inverting input end of the second operational amplifier X2.

[0099] The resistors and capacitors in the embodiment form an anti-overshoot structure to prevent damage to the elements in the circuit caused by static electricity and other interference.

[0100] In the above embodiment, the output end of the comparison circuit 4 is connected to the MCU 6. In a specific implementation, in order to protect the MCU 6, the off detection circuit of the myoelectric signal collection electrode plate further includes: an eleventh resistor R11, a first zener diode D1, and a second zener diode D2.

[0101] The anode of the first zener diode D1 is connected to the output end of the comparison circuit 4, the cathode of the first zener diode D1, the first end of the eleventh resistor R11, and the cathode of the second zener diode D2 are commonly connected to the MCU 6, and the second end of the eleventh resistor R11 and the anode of the second zener diode D2 are commonly grounded.

[0102] The embodiment protects the MCU by voltage division of the zener diodes and the eleventh resistor, and also avoids breakdown of the elements in the circuit.

[0103] As can be known from the above embodiment, the myoelectric signal in the embodiment is small, the voltage in the circuit is low, and the interference of multiple harmonics on the weak current system is particularly serious. In order to reduce the interference of harmonics on the weak current system, the embodiment further includes: a filter circuit.

[0104] The filter circuit is connected to the power supply and the power supply ends of the first operational amplifier X1, the second operational amplifier X2, the third operational amplifier X3, and the fourth operational amplifier X4.

[0105] The filter circuit provided by the embodiment is connected to the power supply in the circuit to filter the input voltage and reduce interference.

[0106] The falling detection circuit of the myoelectric signal collection electrode plate provided by the application is described in detail above. The embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be understood by referring to each other. For the device disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and the relevant parts can be understood by referring to the method part. It should be pointed out that for ordinary technical personnel in the technical field, some improvements and modifications can be made to the application without departing from the principles of the application, and these improvements and modifications also fall within the protection scope of the claims of the application.

[0107] It should also be noted that in this specification, relationship terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or device. Without further limitation, the element defined by the statement "including a" does not exclude the presence of other identical elements in the process, method, article or device including the element.

Claims

1. A falling-off detection circuit of an electromyogram signal collection electrode plate, characterized by, include: Comparator circuit, voltage regulation circuit, reference voltage source, MCU, first isolation circuit and second isolation circuit; The output terminal of the voltage regulation circuit and the first electrode plate are connected to the first terminal of the comparison circuit through the first isolation circuit, which is used to process the electromyographic signals collected by the first electrode plate and then transmit them to the comparison circuit for comparison. The output terminal of the voltage regulation circuit and the second electrode plate are connected to the second terminal of the comparison circuit through the second isolation circuit, which is used to process the electromyographic signals collected by the second electrode plate and then transmit them to the comparison circuit for comparison. The output terminal of the reference voltage source is connected to the third and fourth terminals of the comparator circuit to provide a reference voltage for the comparator circuit. The MCU is connected to the output terminal of the comparator circuit and is used to obtain the comparison result of the comparator circuit and determine the detachment state of the electrode plate based on the comparison result. The voltage regulation circuit includes: First resistor and second resistor; The first end of the first resistor and the first end of the second resistor are connected together, and together they serve as the output terminal of the voltage regulation circuit, connecting the first isolation circuit and the second isolation circuit; the second end of the first resistor is connected to the power supply, and the second end of the second resistor is grounded; The first isolation circuit includes: First operational amplifier and first capacitor; The non-inverting input terminal of the first operational amplifier is connected to the output terminal of the voltage regulation circuit, the first plate, and the first terminal of the first capacitor; The output terminal of the first operational amplifier is connected to the inverting input terminal of the first operational amplifier and the first terminal of the comparator circuit; The second terminal of the first capacitor is grounded; The second isolation circuit includes: a second operational amplifier and a second capacitor; The non-inverting input of the second operational amplifier is connected to the output of the voltage regulation circuit, the second plate, and the first terminal of the second capacitor; The output terminal of the second operational amplifier is connected to the inverting input terminal of the second operational amplifier and the second terminal of the comparator circuit; The second terminal of the second capacitor is grounded; The comparison circuit includes: Third operational amplifier, fourth operational amplifier, third resistor, fourth resistor, fifth resistor, sixth resistor; The first end of the third resistor is connected to the output terminal of the first operational amplifier as the first terminal of the comparator circuit, and the second end of the third resistor is connected to the non-inverting input terminal of the third operational amplifier. The first end of the fourth resistor is connected to the output terminal of the second operational amplifier as the second end of the comparator circuit, and the second end of the fourth resistor is connected to the non-inverting input terminal of the fourth operational amplifier. The inverting input terminal of the third operational amplifier serves as the third terminal of the comparator circuit, and the inverting input terminal of the fourth operational amplifier serves as the fourth terminal of the comparator circuit; both are connected to the output terminal of the reference voltage source. The first end of the fifth resistor is connected to the power supply, the second end of the fifth resistor is connected to the output of the third operational amplifier and the first end of the sixth resistor, and the second end of the sixth resistor is connected to the output of the fourth operational amplifier, together serving as the output of the comparator circuit connected to the MCU.

2. The off detection circuit of the myoelectric signal acquisition electrode plate according to claim 1, characterized in that, The reference voltage source comprises: a seventh resistor, an eighth resistor, and a third capacitor; a first end of the seventh resistor is connected to a power supply, a first end of the eighth resistor and a first end of the third capacitor are commonly grounded, a second end of the seventh resistor, a second end of the eighth resistor, and a second end of the third capacitor are commonly connected to an inverting input end of the third operational amplifier and an inverting input end of the fourth operational amplifier as an output end of the reference voltage source.

3. The off detection circuit of the myoelectric signal acquisition electrode plate according to claim 1, characterized in that, Further comprising: a ninth resistor, a tenth resistor, a fourth capacitor, and a fifth capacitor; a first end of the ninth resistor and a first end of the fourth capacitor are commonly connected to an output end of the voltage regulating circuit, a second end of the fourth capacitor is grounded, and a second end of the ninth resistor is connected to a non-inverting input end of the first operational amplifier; a first end of the tenth resistor and a first end of the fifth capacitor are commonly connected to the output end of the voltage regulating circuit, a second end of the fifth capacitor is grounded, and a second end of the tenth resistor is connected to a non-inverting input end of the second operational amplifier.

4. The off detection circuit of the myoelectric signal acquisition electrode plate according to claim 1, characterized in that, Further comprising: an eleventh resistor, a first zener diode, and a second zener diode; an anode of the first zener diode is connected to an output end of the comparison circuit, a cathode of the first zener diode, a first end of the eleventh resistor, and a cathode of the second zener diode are commonly connected to the MCU, and a second end of the eleventh resistor and an anode of the second zener diode are commonly grounded.

5. The off detection circuit of the myoelectric signal acquisition electrode plate according to claim 1, characterized in that, Further comprising: a filter circuit; the filter circuit is connected to a power supply and power supply ends of the first operational amplifier, the second operational amplifier, the third operational amplifier, and the fourth operational amplifier.

6. The off detection circuit of the myoelectric signal acquisition electrode plate according to claim 1, characterized by, Further comprising: an alarm device; the alarm device is connected to the MCU.

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