CN113876336A - Dynamic switching device and dynamic switching method for myoelectricity acquisition reference electrode - Google Patents
Dynamic switching device and dynamic switching method for myoelectricity acquisition reference electrode Download PDFInfo
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Abstract
The application provides a dynamic switching device and a dynamic switching method for a myoelectricity acquisition reference electrode. The dynamic switching apparatus includes: measuring electrodes of a plurality of channels; the positive electrode input end of the programmable gain amplification circuit is connected with the output end of the measuring electrode; the external reference electrode is connected with the programmable gain amplification circuit through the reference electrode dynamic switching circuit; when the reference electrode dynamic switching circuit is in a first state, the external reference electrode is connected with the negative electrode input ends of all the programmable gain amplification circuits so as to switch the reference electrode for myoelectricity acquisition to the external reference electrode; when the reference electrode dynamic switching circuit is in the second state, the positive output ends of all the programmable gain amplifying circuits are connected with the negative input end of the programmable gain amplifying circuit after voltage mean value sampling to form a negative feedback loop so as to switch the reference electrode for myoelectricity acquisition to the average reference electrode.
Description
Technical Field
The application relates to the technical field of medical detection, in particular to a dynamic switching device and a dynamic switching method for a myoelectricity acquisition reference electrode.
Background
The surface electromyographic signals (sEMG) of the human body are the combined effects of the electromyographic signals of superficial muscles and the neuroelectrical activity on the skin surface, and contain various information of the nerve and muscle activity. The surface myoelectric signals are collected, analyzed and processed, so that the information of the physiological state, the movement intention, the action mode and the like of the human body can be obtained, and the method has important application value in the aspects of clinical medicine, rehabilitation engineering, biological machinery and the like and is widely applied.
The existing multi-channel surface electromyography acquisition equipment only can select one of an external reference electrode or an average reference electrode, and cannot dynamically switch the reference electrode from hardware. Although some devices can calculate the average value of all measurement channels through software to serve as a virtual average reference electrode to realize analog switching of the reference electrode, the device still needs to collect the potential of each channel by taking an external reference electrode as a reference, so that the problem that the input signal cannot be normally collected due to the fact that the input signal exceeds the range still exists.
Disclosure of Invention
The application provides a dynamic switching device and a dynamic switching method for a myoelectricity acquisition reference electrode.
The application provides a dynamic switching device of reference electrode is gathered to flesh electricity, dynamic switching device includes:
measuring electrodes of a plurality of channels;
the positive electrode input end of the programmable gain amplification circuit is connected with the output end of the measuring electrode;
the external reference electrode is connected with the programmable gain amplifying circuit through a reference electrode dynamic switching circuit;
when the reference electrode dynamic switching circuit is in a first state, the external reference electrode is connected with the negative input ends of all the programmable gain amplification circuits so as to switch the reference electrode for myoelectricity acquisition to the external reference electrode; when the reference electrode dynamic switching circuit is in the second state, all the positive output ends of the programmable gain amplifying circuits are connected with the negative input end of the programmable gain amplifying circuits after voltage mean value sampling to form a negative feedback loop so as to switch the reference electrode for myoelectricity acquisition to an average reference electrode.
The reference electrode dynamic switching circuit comprises a first channel switch of a plurality of channels, a second channel switch of the plurality of channels, a first switch and a second switch.
When the reference electrode dynamic switching circuit is in a first state, the first channel switch, the second channel switch and the first switch of the plurality of channels are closed, and the second switch is opened, so that the negative electrode input end of the programmable gain amplification circuit is connected with the external reference electrode.
When the reference electrode dynamic switching circuit is in a second state, the first channel switches and the second switching switches of the channels are closed, and the second channel switches and the first switching switches of the channels are opened, so that all the positive output ends of the programmable gain amplifying circuits are connected with the negative input end of the programmable gain amplifying circuits after voltage mean value sampling, and a negative feedback loop is formed.
The reference electrode dynamic switching circuit further comprises a plurality of channels of current limiting resistors, wherein a voltage mean value sampling circuit is formed by the first channel switches, the second channel switches and the current limiting resistors of the plurality of channels and is used for gating the anode output end and the cathode output end of the programmable gain amplifying circuit to a common mode reference point to obtain the average voltage of all gating signals.
When the reference electrode dynamic switching circuit is in the third state, the first channel switch and the second channel switch of the target channel are switched off, so as to switch off the measuring electrode corresponding to the target channel.
The application also provides a dynamic switching method of the myoelectricity acquisition reference electrode, which comprises the following steps:
collecting surface electromyographic signals by using discrete patch electrodes, wherein an external reference electrode is selected as a reference electrode;
judging whether the amplitude of the surface electromyographic signal reaches the preset range of the channel;
if yes, switching the reference electrode into an average reference electrode through a dynamic switching device;
the dynamic switching device is the dynamic switching device.
Wherein, the dynamic switching method further comprises:
acquiring the impedance of the measuring electrode based on the surface electromyographic signal of each channel;
judging whether the impedance of the measuring electrode is larger than a preset impedance value or not;
if yes, ignoring the surface electromyographic signals of the channel measuring electrodes.
The application also provides another dynamic switching method of the myoelectricity acquisition reference electrode, which comprises the following steps:
collecting surface electromyographic signals by using an array patch electrode, wherein a reference electrode is an average reference electrode;
judging whether the number of the measuring electrodes corresponding to the surface electromyographic signals is smaller than a preset number or not;
if yes, switching the reference electrode into an external reference electrode through a dynamic switching device;
wherein the dynamic switching device is the dynamic switching device of any one of claims 1 to 6.
Wherein, the dynamic switching method further comprises:
acquiring the impedance of the measuring electrode based on the surface electromyographic signal of each channel;
judging whether the impedance of the measuring electrode is larger than a preset impedance value or not;
if yes, ignoring the surface electromyographic signals of the channel measuring electrodes.
The beneficial effect of this application is: the dynamic switching device includes: measuring electrodes of a plurality of channels; the positive input end of the programmable gain amplification circuit is connected with the output end of the measuring electrode; the external reference electrode is connected with the programmable gain amplification circuit through the dynamic switching reference circuit; when the dynamic switching reference circuit is in a first state, the external reference electrode is connected with the negative input end of the programmable gain amplification circuit so as to switch the reference electrode of the dynamic switching device to the external reference electrode; when the dynamic switching reference circuit is in the second state, the anode output end of the programmable gain amplifying circuit is connected with the cathode input end of the programmable gain amplifying circuit so as to switch the reference electrode of the dynamic switching device to the average reference electrode. Through the mode, the dynamic switching device can realize dynamic switching of the reference electrode from hardware.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts. Wherein:
fig. 1 is a schematic structural diagram of an embodiment of a dynamic switching device for a myoelectricity collection reference electrode provided in the present application;
FIG. 2 is a schematic structural diagram of another embodiment of the dynamic switching device for the myoelectricity collection reference electrode provided in the present application;
FIG. 3 is a schematic structural diagram of a dynamic switching device of a myoelectricity collection reference electrode according to another embodiment of the present application;
fig. 4 is a schematic flow chart of an embodiment of a dynamic switching method of a myoelectricity collection reference electrode provided in the present application;
FIG. 5 is a schematic flow chart of another embodiment of a method for dynamically switching a myoelectricity collection reference electrode according to the present application
Fig. 6 is a schematic structural diagram of an embodiment of a terminal device provided in the present application;
FIG. 7 is a schematic structural diagram of an embodiment of a computer storage medium provided in the present application.
Detailed Description
The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
The multichannel surface electromyography acquisition equipment is generally composed of modules such as a measuring electrode, a reference electrode, filtering, Programmable Gain Amplification (PGA), Right Leg Drive (RLD), analog-to-digital conversion (ADC), data processing and the like. The measuring electrode is used for collecting electromyographic signals on the surface of skin, and a silver-silver chloride discrete patch electrode and an array electrode integrated on a Flexible Printed Circuit (FPC) are commonly used. The reference electrode is used for providing a potential reference point, and in order to reduce the number of electrode wires when multi-channel surface electromyogram signal acquisition is carried out, negative polarity input ends of all channels are usually connected together to share one reference electrode. Theoretically, the reference electrode should be selected as a zero potential point of a body or an infinite point, but the zero potential point does not exist in the body actually, and the tissues of arms, legs and the like which are usually used for measuring surface myoelectric signals are not similar to a closed sphere of a head, so that the myoelectric potential value based on the specific reference electrode can not be converted into a potential value taking the infinite point on the space as a reference by using a common reference electrode standardization technology during electroencephalogram acquisition. Therefore, the reference electrode of the myoelectric acquisition device generally has two selection modes: firstly, external electrodes placed at specific parts with inactive myoelectricity, such as elbows, knees and the like, are used as reference electrodes, namely external reference electrodes; and secondly, the reference electrode wire is not led out outwards, the average value of the electric potentials of all the measuring electrodes is calculated in a software or hardware mode and is used as a reference electrode, namely an average reference electrode. The two reference electrodes each have the advantage that the external reference electrode can provide a relatively stable, comparable and reproducible near zero potential; the average reference electrode can effectively inhibit common-mode interference by subtracting the average value of all channels, reduce the requirements on the measuring range and the dynamic range of the AD converter and reduce one electrode wire.
In practical applications, both currently used reference electrodes have certain limitations:
the external reference electrode is adapted for use with a discrete patch electrode. When the sEMG waveform acquisition device is matched with an array electrode, due to the fact that the density of the array electrode is large, the contact impedance between the array electrode and the skin is large due to the fact that the contact surface between a single electrode and the skin is small, the difference between the contact impedance and the skin is large, the potential difference between the array electrode and the skin is too large, the range of the programmable gain amplification or the analog-to-digital conversion circuit can be exceeded, and the sEMG waveform cannot be acquired normally.
The average reference electrode is adapted for use with the array electrode. When combined with a small number or uneven distribution of discrete patch electrodes, the potential of the average reference electrode is not always stable, and may be active and constantly changing over time, which introduces an unknown dynamic potential to all measurement electrodes, resulting in the measured sEMG waveform losing some useful information and being unable to be analyzed against historical or similar data.
Therefore, when measuring electrodes with different characteristics such as discrete patch electrodes or array electrodes are used, the multi-channel surface electromyography acquisition device needs to be switched between the two reference electrodes. In some cases, in order to ensure smooth myoelectricity acquisition test, the reference electrode needs to be dynamically switched from hardware, and if the input signal exceeds the measuring range due to the drift of electrode contact impedance in the acquisition process, the external reference electrode needs to be switched to the average reference electrode; when the number of useful signal channels is too small or the distribution is obviously uneven due to the falling off or damage of some electrodes, the average reference electrode needs to be switched to an external reference electrode.
For solving the problem that the current multichannel surface myoelectricity collection equipment can not dynamically switch the reference electrode from hardware to adapt to different measuring electrodes or measuring environments, the application provides a novel dynamic switching device based on the myoelectricity collection reference electrode.
Referring to fig. 1 in detail, fig. 1 is a schematic structural diagram of an embodiment of a dynamic switching device for a myoelectricity collection reference electrode provided in the present application.
As shown in fig. 1, the myoelectricity collection reference electrode dynamic switching device 100 according to the embodiment of the present application at least includes a plurality of channels of measurement electrodes 11, a programmable gain amplification circuit 12, a reference electrode dynamic switching circuit 13, and an external reference electrode 14.
The positive input end of the programmable gain amplifying circuit 12 is connected with the output end of the measuring electrode 11, and the external reference electrode 14 is connected with the programmable gain amplifying circuit 12 through the reference electrode dynamic switching circuit 13.
Specifically, the reference electrode dynamic switching circuit 13 of the embodiment of the present application operates as follows: when the reference electrode dynamic switching circuit 13 is in the first state, the external reference electrode 14 is connected to the negative input terminal of the programmable gain amplifying circuit 12, so as to switch the reference electrode of the dynamic switching device 100 to the external reference electrode 14; when the dynamic reference electrode switching circuit 13 is in the second state, the positive output terminal of the programmable gain amplifier circuit 12 is connected to the negative input terminals of all the programmable gain amplifier circuits 12 to form negative feedback, and the voltage at the negative input terminal is clamped to the average value at the positive input terminal, instead of the average value at the positive output terminal amplified by the programmable gain amplifier circuit 12, so that the reference electrode of the dynamic switching device 100 is switched to the average reference electrode.
The reference electrode dynamic switching circuit 13 of the embodiment of the present application specifically includes a first channel switch with a plurality of channels, a second channel switch with a plurality of channels, a first switch, and a second switch. The number of the first transfer switch and the number of the second transfer switch are both one, and the number of the first channel switch and the number of the second channel switch are consistent with the number of the channels of the measuring electrode 11.
Specifically, the reference electrode dynamic switching circuit 13 is in a first state, that is, the first channel switches of the plurality of channels, the second channel switches of the plurality of channels, and the first switch are closed, and the second switch is opened, so that the negative input terminal of the programmable gain amplification circuit 12 is connected to the external reference electrode 14.
The reference electrode dynamic switching circuit 13 is in the second state, that is, the first channel switches and the second switching switches of the plurality of channels are closed, and the second channel switches and the first switching switches of the plurality of channels are opened, so that the positive output end of the programmable gain amplifying circuit 12 is connected to the negative input end of the programmable gain amplifying circuit 12.
The reference electrode dynamic switching circuit 13 is in a third state, that is, the first channel switch and the second channel switch of a certain channel are both turned off, so that the measuring electrode of the channel is short-opened to shield the surface electromyogram signal measured by the falling measuring electrode.
The reference electrode dynamic switching circuit 13 further includes current limiting resistors of several channels, that is, the number of the current limiting resistors is positively correlated to the number of the measuring electrodes. The first channel switch, the second channel switch and the current-limiting resistor of the plurality of channels may form a voltage-average sampling circuit, and the voltage-average sampling circuit may be configured to gate the positive output terminal and the negative output terminal of the programmable gain amplifier circuit 12 to a common mode reference point.
The dynamic switching device of the embodiment of the application comprises: measuring electrodes of a plurality of channels; the positive input end of the programmable gain amplification circuit is connected with the output end of the measuring electrode; the external reference electrode is connected with the programmable gain amplification circuit through the reference electrode dynamic switching circuit; when the reference electrode dynamic switching circuit is in a first state, the external reference electrode is connected with the negative input end of the programmable gain amplification circuit so as to switch the reference electrode of the dynamic switching device to the external reference electrode; when the reference electrode dynamic switching circuit is in the second state, the anode output end of the programmable gain amplifying circuit is connected with the cathode input end of the programmable gain amplifying circuit so as to switch the reference electrode of the dynamic switching device to the average reference electrode. Through the mode, the dynamic switching device can realize dynamic switching of the reference electrode from hardware.
According to the embodiment of the application, the external reference electrode and the average reference electrode are dynamically switched from hardware, so that the existing multi-channel electromyography acquisition equipment can be better adapted to measuring electrodes with different properties such as discrete patch electrodes and array electrodes, the situation that surface electromyography signals cannot be acquired due to overlarge drift of electrode measuring impedance or useful information of the surface electromyography signals is lost due to the situations of small quantity of the measuring electrodes, uneven distribution and the like is avoided. The accuracy, data integrity and efficiency of surface electromyogram signal acquisition are improved. In addition, the embodiment of the application also skillfully introduces negative feedback in the programmable gain amplifying circuit, and the sampling point of the average reference voltage is arranged behind the programmable gain amplifying circuit and is the same as the voltage sampling point of the right leg driving circuit, but not in front of the programmable gain amplifying circuit in the prior art. The invention can be conveniently integrated into the existing myoelectricity acquisition equipment or chip, is flexible and convenient to use and reduces the use cost.
The functions implemented by the dynamic switching device protected by the embodiments of the present application will be further described below by a specific dynamic switching device. With reference to fig. 2, fig. 2 is a schematic structural diagram of another embodiment of the dynamic switching device for the myoelectric acquisition reference electrode provided in the present application.
As shown in fig. 2, the dynamic switching device provided in the embodiment of the present application is composed of an electrode, a filter, a Programmable Gain Amplifier (PGA), a reference electrode dynamic switching circuit, a Right Leg Driver (RLD), and an analog to digital converter (ADC) circuit. The core of the multi-channel myoelectricity acquisition device is a reference electrode dynamic switching circuit, and other parts such as electrodes, filtering, PGA, RLD and ADC circuits can use corresponding modules of the existing multi-channel myoelectricity acquisition device.
Therefore, the dynamic switching device can be used independently, and can also be integrated into the existing multi-channel myoelectricity acquisition equipment to be matched with the existing multi-channel myoelectricity acquisition equipment for use.
When used alone, referring to fig. 2, the electrodes include a measurement electrode, an external reference electrode, and a right leg drive electrode, all of which are attached to the skin surface of the human body. The measuring electrode is used for collecting myoelectric signals on the surface of the skin, and the signals are introduced to the positive polarity input end of the PGA; the external reference electrode is attached to the approximate zero potential points of the elbow, knee and the like of a human body, provides potential reference for each channel and is led to the negative polarity input end of the PGA; the right leg driving electrode is used for establishing a closed loop negative feedback path between a common mode signal of the measuring electrode and a human body and reducing external noise interference.
The filter circuit consists of an RC low-pass filter and is used for filtering high-frequency noise of signals input from the measuring electrode and the external reference electrode and avoiding aliasing in the subsequent analog-digital sampling process. The resistance, precision and temperature coefficient of the resistor and the capacitor of each channel filter circuit are the same so as to better inhibit common mode interference.
The PGA circuit includes operational amplifiers OPxA and OPxB (x is 1,2, …, n) and resistors R1 and R2, and is configured to amplify a differential mode component of an input signal, suppress a common mode component, and increase an input impedance of the circuit. UixP and UixN are respectively the positive and negative polarity input ends of the PGA circuit, and UoxP and UoxN are respectively the positive and negative polarity output ends of the PGA circuit. The gain of the PGA circuit can be adjusted by adjusting the resistance of R2.
The reference electrode dynamic switching circuit is composed of switches SxP and SxN (x is 1,2, …, n), SR1, SR2, a resistor R3, and an operational amplifier OPRA. The switches SxP, SxN and the current-limiting resistor R3 constitute a voltage-mean sampling circuit for gating the signals of the PGA output terminals UoxP, UoxN to the common-mode reference point Uc, which is the mean value of all the gating signals.
If a certain channel is no longer in use due to electrode falling off, the switches SxP and SxN corresponding to the channel should be turned off, that is, the third state in the above embodiment is corresponded.
SxP, SxN are also used together with SR1, SR2 to realize the function of dynamically switching the reference electrode, and the working principle is as follows: SxP and SxN of the channels in use are closed, SR1 is closed at the same time, SR2 is opened, so that the negative polarity input end UixN of PGA is directly connected with the filtered external reference electrode, and the reference electrode is switched to the external reference electrode, namely, the first state in the above embodiment is corresponded. SxP of the channel used is closed, SxN is opened, SR2 is closed at the same time, SR1 is opened, so that the positive polarity output end UoxP of the PGA is connected with the negative polarity input end UixN, negative feedback is formed, the voltage of UixN is clamped to the average value of the positive polarity input end UixP of the PGA instead of the average value of the UoxP amplified by the PGA, and the reference electrode is switched to the average reference, namely, the reference electrode corresponds to the second state in the above embodiment.
Further, the operational amplifier OPRA is used as an emitter follower for isolating the reference electrode dynamic switching from the input signal of the RLD circuit and avoiding mutual interference. It should select the precision operational amplifier whose input offset voltage is not more than 10V, so that it can not produce obvious error when following the surface electromyogram signal whose amplitude is weak.
The RLD circuit is composed of an inverse proportional operational circuit composed of an operational amplifier OPRC, a resistor Rf and a capacitor Cf, and an emitter follower composed of an operational amplifier OPRB. A closed-loop feedback compensation system is established by negative feedback amplification of common-mode voltages of input signals of all measurement channels, and common-mode interference can be effectively inhibited. When the reference electrode dynamic switching circuit is used for switching reference, the common mode reference point Uc is always the common mode voltage of all input signals due to different opening and closing modes of the switches SxP, SxN, SR1 and SR 2. VRLDREF is used to provide a dc reference voltage to the output of the inverse proportional arithmetic circuit and the human body, which is typically half the ADC supply voltage. To establish an effective negative feedback path, the resistance of the feedback resistor Rf should be more than 10 times that of the input resistor R3. The emitter follower is used for isolating the dynamic switching of the reference electrode and the input signal of the RLD circuit and avoiding mutual interference, and the OPRB should adopt a precise operational amplifier with the input offset voltage not exceeding 10V.
The ADC circuit is used for converting the amplified surface myoelectric analog signal output by the PGA into a digital signal, and sending the digital signal to a microprocessor such as a singlechip and a DSP through a communication interface for further processing such as subsequent storage and analysis.
When the device is used with an existing multi-channel myoelectricity collection device, please refer to fig. 3, where fig. 3 is a schematic structural diagram of another embodiment of the dynamic switching device for the myoelectricity collection reference electrode provided in the present application. The ADS1298 multi-channel myoelectricity acquisition front-end chip commonly used by the existing multi-channel myoelectricity acquisition equipment is used for illustration, and other myoelectricity acquisition chips are similar to the principle framework thereof, and the embodiment can also be referred to.
The ADS1298 chip integrates modules such as a multiplexer, a PGA and an ADC (a part of the modules and pins are not shown), and each PGA positive and negative polarity output terminals can be collected to the RLDINV pin through a 220k Ω current-limiting resistor and controlled by programmable analog switches RLDxP and RLDxN (x is 1,2, …, n). It can be seen that the RLDxP, RLDxN, 220k Ω current limiting resistors can replace SxP, SxN, R3 in fig. 2 to play the same role, while the RLDINV pin is the common mode reference point Uc. In order to realize the dynamic switching function of the reference electrode in the embodiment of the present application, it is only necessary to add the operational amplifier OPRA, the programmable analog switches SR1 and SR2, and the RLD circuit in fig. 2, which is very convenient. When surface electromyogram signals are collected, if the reference electrode needs to be switched to external reference, RLDxP and RLDxN of a channel used in use can be closed, SR1 is closed, and SR2 is disconnected; if it is desired to switch the reference electrode to the average reference, SxN for the in-use channel may be opened while SR2 is closed and SR1 is opened.
The following continues the description of the potential signal variation of the dynamic switching device of fig. 2 in combination with the reference electrode dynamic switching:
when the dynamic switching device for the electromyography acquisition reference electrode is used for acquiring sEMG signals, firstly, according to whether a measurement electrode is a discrete patch electrode or an array electrode, an external reference or an average reference is correspondingly selected as the reference electrode, wherein if the measurement electrode is the discrete patch electrode, the external reference electrode is selected; if the measurement electrode is an array electrode, an average reference electrode should be selected.
For example, if the measurement electrode is a discrete patch electrode, SxP and SxN (x ═ 1,2, …, n) of the in-use channels can be closed, while SR1 is closed, SR2 is opened, and the reference electrode is switched to the external reference. At this time, the negative input terminal potential of the PGA circuit is:
UixN＝UR
the operational amplifiers OPxA and OPxB of the PGA circuit are in a negative feedback linear amplification state, and the following results are obtained:
namely:
the above equation gives the gain of the PGA, which can be adjusted by R2. Therefore, the potentials of the PGA positive output terminal and the PGA negative output terminal are respectively:
from this, the voltage of the common mode reference point Uc is:
according to the formula, the common-mode reference point Uc is the common-mode voltage of all the input signals of the measuring channels, and after the common-mode reference point Uc is introduced into the RLD circuit, the common-mode voltage is fed back to a human body through the right leg driving electrode, so that common-mode interference can be effectively inhibited.
Furthermore, when the external reference electrode is used as the reference electrode, whether the electrode falls off is detected by measuring electrode impedance and the like, if the electrode falls off is detected, myoelectric acquisition data of an electrode falling channel is ignored, and switches SxP and SxN of the falling channel are disconnected.
During the acquisition process, myoelectricity acquisition data of a normally used channel is monitored in real time, and if the data of a certain channel exceeds the range of the channel, the duration is longer (for example, more than 10 seconds). After the external electromagnetic interference factors are eliminated, the reason is considered to be that the zero drift of the electromyographic signals is too large to exceed the range of the ADC due to large variation of contact impedance between the external reference electrode and the skin and the measurement electrode.
At this time, in order to ensure the correct acquisition of the surface electromyogram data and the smooth performance of the test, the external reference electrode can be switched to the average reference electrode, that is, SxN of the channel used is disconnected, meanwhile, SR2 is closed, SR1 is disconnected, and the positive polarity output end UOXP of the PGA is connected with the negative polarity input end UixN through the common mode reference point Uc. At this time, the negative input terminal potential of the PGA circuit is:
UixN＝Uc
the operational amplifiers OPxA and OPxB of the PGA circuit are still in a negative feedback linear amplification state, and the following results can be obtained:
therefore, the PGA can still effectively amplify the differential mode component of the input signal with the same gain as when using the external reference electrode. The potential of the positive polarity output terminal of the PGA at this time is:
further, the voltage of the common mode reference point Uc obtained by adding the potentials of all the PGA positive polarity output terminals is:
namely:
therefore, although the PGA amplifies the differential mode component of the input signal of the measurement channel, the positive output terminal and the negative input terminal of the PGA are connected to form a negative feedback loop, so that the voltage of the common mode reference point Uc is still maintained as the common mode voltage of all the input signals, rather than the average value after PGA amplification. It can also be introduced into the RLD loop for rejection of common mode interference.
Furthermore, when the reference electrode uses the average reference electrode, whether the electrode falls off is detected by means of measuring electrode impedance and the like, if the electrode falls off is found, myoelectric acquisition data of an electrode falling channel is ignored, and switches SxP and SxN of the falling channel are turned off.
In the collecting process, the number and the distribution condition of the normally used measuring electrodes are monitored in real time, if the number is too small (for example, less than 8), the distribution is obviously uneven, in order to ensure the correct collection of the surface electromyogram data and the smooth operation of the test, the average reference can be switched to the external reference, namely SxP and SxN of the used channel are closed, meanwhile, SR1 is closed, and SR2 is disconnected.
The dynamic switching device provided by the embodiment of the application can enable the existing multi-channel electromyography acquisition equipment to be better adapted to measurement electrodes with different properties such as discrete patch electrodes and array electrodes by dynamically switching the external reference electrode and the average reference electrode from hardware, so that the situation that the surface electromyography signals cannot be acquired due to overlarge electrode measurement impedance drift or the useful information of the surface electromyography signals is lost due to the situations of small number of measurement electrodes, uneven distribution and the like is avoided. The accuracy, data integrity and efficiency of surface electromyogram signal acquisition are improved; in addition, by skillfully introducing negative feedback into the programmable gain amplification circuit, the sampling point of the average reference voltage is arranged behind the programmable gain amplification circuit and is the same as the voltage sampling point of the right leg driving circuit, rather than in front of the programmable gain amplification circuit in the prior art, so that the dynamic switching device of the embodiment of the application can be conveniently integrated into the existing myoelectricity acquisition equipment or chip, the use is flexible and convenient, and the use cost is reduced.
With reference to fig. 4, fig. 4 is a schematic flowchart illustrating an embodiment of a dynamic switching method for a myoelectric acquisition reference electrode according to the present application.
Specifically, as shown in fig. 4, the dynamic switching method in the embodiment of the present application specifically includes the following steps:
step S11: and collecting surface electromyographic signals by using discrete patch electrodes, wherein the reference electrode is an external reference electrode.
The dynamic switching device of the electromyography acquisition reference electrode is used for acquiring sEMG signals, and when the measuring electrode is a discrete patch electrode, an external reference electrode is correspondingly selected as the reference electrode.
Step S12: and judging whether the amplitude of the surface electromyographic signal reaches the preset range of the channel.
In the collecting process, the dynamic switching device needs to determine whether the amplitude of the collected surface electromyogram signal is larger than the preset range of the channel, and if so, the process goes to step S13.
Specifically, during the acquisition process, myoelectricity acquisition data of a normally used channel is monitored in real time, and if the data of a certain channel exceeds the range of the channel, the duration is long (for example, more than 10 seconds). After the external electromagnetic interference factors are eliminated, the reason is considered to be that the zero drift of the electromyographic signals is too large to exceed the range of the ADC due to large variation of contact impedance between the external reference electrode and the skin and the measurement electrode. In order to ensure correct acquisition of the surface electromyogram data and smooth test, the external reference electrode may be switched to the average reference electrode, i.e., the process proceeds to step S13.
Step S13: the reference electrode is switched to the average reference electrode by the dynamic switching means.
For a specific structure and switching logic of the dynamic switching device in the embodiment of the present application, please refer to the dynamic switching device in fig. 1 to 3, which is not described herein again.
Furthermore, when the external reference electrode is adopted as the reference electrode in the embodiment of the application, whether the electrode falls off can be detected in modes of measuring electrode impedance and the like, if the electrode falls off, myoelectric acquisition data of an electrode falling channel is ignored, and switches SxP and SxN of the falling channel are disconnected.
With reference to fig. 5, fig. 5 is a schematic flow chart of another embodiment of a dynamic switching method of a myoelectric acquisition reference electrode according to the present application.
Specifically, as shown in fig. 5, the dynamic switching method in the embodiment of the present application specifically includes the following steps:
step S21: and collecting surface electromyographic signals by using an array patch electrode, wherein the reference electrode is an average reference electrode.
The dynamic switching device of the electromyography acquisition reference electrode is used for acquiring sEMG signals, and when the measuring electrode is an array electrode, an average reference electrode is correspondingly selected as a reference electrode.
Step S22: and judging whether the number of the measuring electrodes corresponding to the surface electromyogram signals is less than the preset number.
In the collecting process, the dynamic switching device needs to monitor the number and the distribution condition of the normally used measuring electrodes in real time, so as to judge whether the number of the measuring electrodes corresponding to the surface electromyogram signals is smaller than a preset number or whether the distribution of the measuring electrodes corresponding to the surface electromyogram signals is obviously uneven. Wherein the preset number may be set to 8 or other values. If yes, the process proceeds to step S23.
Step S23: and switching the reference electrode into an external reference electrode through a dynamic switching device.
For a specific structure and switching logic of the dynamic switching device in the embodiment of the present application, please refer to the dynamic switching device in fig. 1 to 3, which is not described herein again.
Furthermore, when the average reference electrode is used as the reference electrode, the embodiment of the application can detect whether the electrode falls off or not by measuring the impedance of the electrode, and the like, and if the electrode falls off, the myoelectric data acquisition of the electrode falling channel is ignored, and the switches SxP and SxN of the falling channel are turned off.
It will be understood by those skilled in the art that in the method of the present invention, the order of writing the steps does not imply a strict order of execution and any limitations on the implementation, and the specific order of execution of the steps should be determined by their function and possible inherent logic.
In order to implement the method for dynamically switching the myoelectricity acquisition reference electrode according to the above embodiment, the present application further provides a terminal device, and specifically refer to fig. 6, where fig. 6 is a schematic structural diagram of another embodiment of the terminal device provided in the present application.
The terminal device 600 of the embodiment of the present application includes a memory 61 and a processor 62, wherein the memory 61 and the processor 62 are coupled.
The memory 61 is used for storing program data, and the processor 62 is used for executing the program data to realize the dynamic switching method of the myoelectricity collection reference electrode according to the above-mentioned embodiment.
In the present embodiment, the processor 62 may also be referred to as a CPU (Central Processing Unit). The processor 62 may be an integrated circuit chip having signal processing capabilities. The processor 62 may also be a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other Programmable logic device, discrete gate or transistor logic, discrete hardware components. A general purpose processor may be a microprocessor or the processor 62 may be any conventional processor or the like.
The present application further provides a computer storage medium, as shown in fig. 7, the computer storage medium 700 is used to store program data 71, and when the program data 71 is executed by a processor, the program data is used to implement the method for dynamically switching the electromyographic acquisition reference electrode according to the above embodiment.
The present application further provides a computer program product, wherein the computer program product includes a computer program operable to cause a computer to execute the method for dynamically switching the electromyographic acquisition reference electrode according to the embodiment of the present application. The computer program product may be a software installation package.
The method for dynamically switching the myoelectric acquisition reference electrode according to the above embodiments of the present application may be stored in a device, for example, a computer readable storage medium, when the method is implemented in the form of a software functional unit and sold or used as an independent product. Based on such understanding, the technical solution of the present application may be substantially implemented or contributed by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) or a processor (processor) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.
The above description is only for the purpose of illustrating embodiments of the present application and is not intended to limit the scope of the present application, and all modifications of equivalent structures and equivalent processes, which are made by the contents of the specification and the drawings of the present application or are directly or indirectly applied to other related technical fields, are also included in the scope of the present application.
Claims (10)
1. A dynamic switching device of a myoelectricity collection reference electrode is characterized by comprising:
measuring electrodes of a plurality of channels;
the positive electrode input end of the programmable gain amplification circuit is connected with the output end of the measuring electrode;
the external reference electrode is connected with the programmable gain amplifying circuit through a reference electrode dynamic switching circuit;
when the reference electrode dynamic switching circuit is in a first state, the external reference electrode is connected with the negative electrode input ends of all the programmable gain amplification circuits so as to switch the reference electrode for myoelectricity acquisition to the external reference electrode; when the reference electrode dynamic switching circuit is in the second state, all the positive output ends of the programmable gain amplifying circuits are connected with the negative input end of the programmable gain amplifying circuits after voltage mean value sampling to form a negative feedback loop so as to switch the reference electrode for myoelectricity acquisition to the average reference electrode.
2. The dynamic switching apparatus of claim 1,
the reference electrode dynamic switching circuit comprises a first channel switch of a plurality of channels, a second channel switch of the plurality of channels, a first switch and a second switch.
3. The dynamic switching apparatus of claim 2,
when the reference electrode dynamic switching circuit is in a first state, the first channel switch, the second channel switch and the first switch of the plurality of channels are closed, and the second switch is opened, so that the negative electrode input end of the programmable gain amplifying circuit is connected with the external reference electrode.
4. The dynamic switching apparatus of claim 2,
when the reference electrode dynamic switching circuit is in a second state, the first channel switches of the channels and the second switching switch are closed, and the second channel switches of the channels and the first switching switch are disconnected, so that all the positive output ends of the programmable gain amplifying circuit are connected with the negative input end of the programmable gain amplifying circuit after voltage mean value sampling, and a negative feedback loop is formed.
5. The dynamic switching apparatus of claim 2,
the reference electrode dynamic switching circuit further comprises a plurality of channels of current limiting resistors, and a voltage mean value sampling circuit is formed by the first channel switches, the second channel switches and the current limiting resistors of the plurality of channels and is used for gating the anode output end and the cathode output end of the programmable gain amplifying circuit to a common mode reference point to obtain the average voltage of all gating signals.
6. The dynamic switching apparatus of claim 2,
and when the reference electrode dynamic switching circuit is in a third state, the first channel switch and the second channel switch of the target channel are disconnected, so that the measuring electrode corresponding to the target channel is disconnected.
7. A dynamic switching method of a myoelectricity collection reference electrode is characterized by comprising the following steps:
collecting surface electromyographic signals by using discrete patch electrodes, wherein an external reference electrode is selected as a reference electrode;
judging whether the amplitude of the surface electromyographic signal reaches the preset range of the channel;
if yes, switching the reference electrode into an average reference electrode through a dynamic switching device;
wherein the dynamic switching device is the dynamic switching device of any one of claims 1 to 6.
8. The dynamic switching method according to claim 7, further comprising:
acquiring the impedance of the measuring electrode based on the surface electromyographic signal of each channel;
judging whether the impedance of the measuring electrode is larger than a preset impedance value or not;
if yes, ignoring the surface electromyographic signals of the channel measuring electrodes.
9. A dynamic switching method of a myoelectricity collection reference electrode is characterized by comprising the following steps:
collecting surface electromyographic signals by using an array patch electrode, wherein a reference electrode is an average reference electrode;
judging whether the number of the measuring electrodes corresponding to the surface electromyographic signals is smaller than a preset number or not;
if yes, switching the reference electrode into an external reference electrode through a dynamic switching device;
wherein the dynamic switching device is the dynamic switching device of any one of claims 1 to 6.
10. The dynamic switching method according to claim 9, further comprising:
acquiring the impedance of the measuring electrode based on the surface electromyographic signal of each channel;
judging whether the impedance of the measuring electrode is larger than a preset impedance value or not;
if yes, ignoring the surface electromyographic signals of the channel measuring electrodes.
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| PCT/CN2021/137586 WO2023029287A1 (en) | 2021-09-02 | 2021-12-13 | Dynamic switching apparatus and dynamic switching method for myoelectricity acquisition reference electrode |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114793947A (en) * | 2022-04-15 | 2022-07-29 | 清华大学 | Animal behavior analysis system and method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101828919A (en) * | 2010-04-28 | 2010-09-15 | 上海诺诚电气有限公司 | Surface electromyographic electrode with amplifying function |
| US20140142458A1 (en) * | 2011-04-08 | 2014-05-22 | Cyberonics, Inc. | Implantable monitoring device with selectable reference channel and optimized electrode placement |
| CN104720786A (en) * | 2013-12-23 | 2015-06-24 | 中国科学院深圳先进技术研究院 | Chip of active electrode for collecting human body surface biological electric signals |
| EP3042607A1 (en) * | 2015-01-12 | 2016-07-13 | Stichting IMEC Nederland | Biopotential signal acquisition system and method |
| CN211674226U (en) * | 2019-11-04 | 2020-10-16 | 北京信息科技大学 | Multichannel bioelectricity signal acquisition system |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6745062B1 (en) * | 1998-10-05 | 2004-06-01 | Advanced Imaging Systems, Inc. | Emg electrode apparatus and positioning system |
| US20080159365A1 (en) * | 2006-12-22 | 2008-07-03 | Branislav Dubocanin | Analog Conditioning of Bioelectric Signals |
| NL1034223C2 (en) * | 2007-08-02 | 2009-02-03 | Twente Medical Systems International Bv | Device for processing signals. |
| EP3241494A1 (en) * | 2016-05-04 | 2017-11-08 | Valtronic Technologies (Holding) SA | Device for detecting or monitoring bioelectrical parameters |
| US10874318B2 (en) * | 2018-03-06 | 2020-12-29 | Cardioinsight Technologies, Inc. | Channel integrity detection and reconstruction of electrophysiological signals |
| JP2020114348A (en) * | 2019-01-18 | 2020-07-30 | ソニー株式会社 | Biological information measurement device |
| CN214017584U (en) * | 2020-06-24 | 2021-08-24 | 江苏德长医疗科技有限公司 | Surface myoelectricity evaluation diagnosis and biofeedback electrical stimulation treatment system |
| CN113229822B (en) * | 2021-05-28 | 2024-08-16 | 西安交通大学 | Portable multi-lead electroencephalogram acquisition system based on capacitive coupling electrode |
-
2021
- 2021-09-02 CN CN202111028370.2A patent/CN113876336B/en active Active
- 2021-12-13 WO PCT/CN2021/137586 patent/WO2023029287A1/en active Application Filing
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101828919A (en) * | 2010-04-28 | 2010-09-15 | 上海诺诚电气有限公司 | Surface electromyographic electrode with amplifying function |
| US20140142458A1 (en) * | 2011-04-08 | 2014-05-22 | Cyberonics, Inc. | Implantable monitoring device with selectable reference channel and optimized electrode placement |
| CN104720786A (en) * | 2013-12-23 | 2015-06-24 | 中国科学院深圳先进技术研究院 | Chip of active electrode for collecting human body surface biological electric signals |
| EP3042607A1 (en) * | 2015-01-12 | 2016-07-13 | Stichting IMEC Nederland | Biopotential signal acquisition system and method |
| CN211674226U (en) * | 2019-11-04 | 2020-10-16 | 北京信息科技大学 | Multichannel bioelectricity signal acquisition system |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114793947A (en) * | 2022-04-15 | 2022-07-29 | 清华大学 | Animal behavior analysis system and method |
| CN114793947B (en) * | 2022-04-15 | 2023-02-03 | 清华大学 | Animal behavior analysis system and method |
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