CN115105102A - Signal acquisition device and myoelectricity acquisition instrument - Google Patents
Signal acquisition device and myoelectricity acquisition instrument Download PDFInfo
- Publication number
- CN115105102A CN115105102A CN202210884663.9A CN202210884663A CN115105102A CN 115105102 A CN115105102 A CN 115105102A CN 202210884663 A CN202210884663 A CN 202210884663A CN 115105102 A CN115105102 A CN 115105102A
- Authority
- CN
- China
- Prior art keywords
- resistor
- module
- differential amplification
- signal
- controllable switch
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
- A61B5/316—Modalities, i.e. specific diagnostic methods
- A61B5/389—Electromyography [EMG]
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
- A61B5/30—Input circuits therefor
- A61B5/301—Input circuits therefor providing electrical separation, e.g. by using isolating transformers or optocouplers
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
- A61B5/30—Input circuits therefor
- A61B5/304—Switching circuits
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
- A61B5/30—Input circuits therefor
- A61B5/307—Input circuits therefor specially adapted for particular uses
- A61B5/313—Input circuits therefor specially adapted for particular uses for electromyography [EMG]
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/72—Signal processing specially adapted for physiological signals or for diagnostic purposes
- A61B5/7225—Details of analog processing, e.g. isolation amplifier, gain or sensitivity adjustment, filtering, baseline or drift compensation
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/72—Signal processing specially adapted for physiological signals or for diagnostic purposes
- A61B5/7235—Details of waveform analysis
- A61B5/725—Details of waveform analysis using specific filters therefor, e.g. Kalman or adaptive filters
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Surgery (AREA)
- General Health & Medical Sciences (AREA)
- Biophysics (AREA)
- Biomedical Technology (AREA)
- Heart & Thoracic Surgery (AREA)
- Medical Informatics (AREA)
- Molecular Biology (AREA)
- Physics & Mathematics (AREA)
- Animal Behavior & Ethology (AREA)
- Pathology (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Signal Processing (AREA)
- Power Engineering (AREA)
- Artificial Intelligence (AREA)
- Computer Vision & Pattern Recognition (AREA)
- Physiology (AREA)
- Psychiatry (AREA)
- Measurement And Recording Of Electrical Phenomena And Electrical Characteristics Of The Living Body (AREA)
Abstract
The invention discloses a signal acquisition device and a myoelectric acquisition instrument, which are applied to the field of signal acquisition.A differential amplification module is used for carrying out differential amplification on an acquired myoelectric signal of a user; the isolation module is connected with the differential amplification module and is used for isolating the user from the rear-stage circuit; and the amplifying module is connected with the isolating module and is used for amplifying and outputting the electromyographic signals. The differential amplification module performs differential amplification on the electromyographic signals, so that the interference-free capacity of the signals is higher, the isolation module isolates a user from a rear-stage circuit, the use safety is improved, and the amplification module amplifies weak electromyographic signals so as to process the electromyographic signals in the following process.
Description
Technical Field
The invention relates to the field of signal acquisition, in particular to a signal acquisition device and a myoelectricity acquisition instrument.
Background
The electromyographic signals are the superposition of action potentials of motor units in a plurality of muscle fibers in time and space. The surface electromyographic signals are the comprehensive effect of the electrical activity of superficial muscles and nerve trunks on the surface of the skin and can reflect the activity of the neuromuscular to a certain extent; the electromyographic signals have the advantages of non-invasiveness, no wound, simplicity in operation and the like in measurement. Therefore, the electromyographic signals have important practical values in clinical medicine, human-computer efficiency, rehabilitation medicine, sports science and the like. However, the myoelectric signals on the surface of the human body are weak and are easily interfered, so that the myoelectric signals are difficult to acquire.
Disclosure of Invention
The invention aims to provide a signal acquisition device and a myoelectricity acquisition instrument, which have stronger interference-free capacity of signals, improve the use safety of the signal acquisition device and facilitate the subsequent processing of myoelectricity signals.
In order to solve the above technical problem, the present invention provides a signal acquisition device, including:
the differential amplification module is used for carrying out differential amplification on the collected electromyographic signals of the user;
the isolation module is connected with the differential amplification module and is used for isolating a user from a rear-stage circuit;
and the amplifying module is connected with the isolating module and is used for amplifying and outputting the electromyographic signals.
Preferably, the differential amplification module comprises an input impedance matching module and a differential amplification module, and the input impedance matching module is connected with the differential amplification module;
the input impedance matching module is used for carrying out impedance matching on the collected electromyographic signals of the user and the differential amplification module;
the differential amplification module is used for carrying out differential amplification on the electromyographic signals of the user.
Preferably, the input impedance matching module includes a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a first capacitor, and a second capacitor;
a first end of the first resistor and a first end of the first capacitor are both connected with the anode of the electromyographic signal, a second end of the first resistor is connected with a first end of the second resistor, a second end of the second resistor is respectively connected with a first end of the third resistor and a first end of the fourth resistor, a second end of the first capacitor is respectively connected with a second end of the third resistor and a second end of the second capacitor, a second end of the fourth resistor is connected with a first end of the fifth resistor, and a second end of the fifth resistor is respectively connected with a second end of the second capacitor and the cathode of the electromyographic signal;
the first resistor and the first capacitor are used for filtering a signal input by the positive pole of the electromyographic signal, the fifth resistor and the second capacitor are used for filtering a signal input by the negative pole of the electromyographic signal, the second resistor and the fourth resistor are used for impedance matching, and the third resistor is used for eliminating noise.
Preferably, the differential amplification module includes a first operational amplifier, a second operational amplifier, a sixth resistor, a seventh resistor, an eighth resistor, and a ninth resistor;
the positive electrode of the electromyographic signal is connected with the positive phase input end of the first operational amplifier, the output end of the first operational amplifier is connected with the first end of the sixth resistor, the connected common end of the first operational amplifier and the first end of the sixth resistor serves as the first output end of the differential amplification module, the second end of the sixth resistor is respectively connected with the inverting input end of the first operational amplifier and the first end of the seventh resistor, and the second end of the seventh resistor is grounded;
the negative electrode of the electromyographic signal is connected with the positive phase input end of the second operational amplifier, the output end of the second operational amplifier is connected with the first end of the eighth resistor, and the connected common end serves as the second output end of the differential amplification module;
the first operational amplifier is used for amplifying a signal input by the positive pole of the electromyographic signal, and the second operational amplifier is used for amplifying a signal input by the negative pole of the electromyographic signal.
Preferably, the power supply further comprises a feedback module, and the feedback module is configured to amplify a median of the voltages output by the differential amplification module in an opposite phase and output the amplified median to the user.
Preferably, the feedback module includes a tenth resistor, an eleventh resistor, and a third operational amplifier, a first end of the tenth resistor is connected to the positive phase output terminal of the differential amplification module, a second end of the eleventh resistor is connected to the negative phase output terminal of the differential amplification module, a second end of the tenth resistor and a second end of the eleventh resistor are connected to the negative phase input terminal of the third operational amplifier, the positive phase input terminal of the third operational amplifier is grounded, and the output terminal of the third operational amplifier is connected to the user;
the tenth resistor and the eleventh resistor have the same resistance value and are used for collecting a median value of the voltage output by the differential amplification module; and the third operational amplifier is used for amplifying the median value and outputting the amplified median value to the user.
Preferably, the power frequency amplifier further comprises a filtering module connected with the amplifying module, and the filtering module is used for filtering power frequency interference of the preset frequency.
Preferably, the isolation module comprises a first controllable switch and a transformer;
the control end of the first controllable switch is connected with a first control signal, the first end of the first controllable switch is respectively connected with the output positive end of the differential amplification module and the first end of the primary coil of the transformer, the second end of the first controllable switch is connected with the second end of the primary coil of the transformer, and the third end of the first controllable switch is connected with the output negative end of the differential amplification module; the first controllable switch is used for controlling the second end of the first controllable switch to be connected with the first end of the first controllable switch or the third end of the first controllable switch according to the first control signal;
the first end of the secondary coil of the transformer is connected with the amplifying module, the second end of the secondary coil of the transformer is grounded, and the transformer is used for amplifying the signal output by the differential amplifying module and then outputting the amplified signal to the amplifying module.
Preferably, the isolation module further comprises a second controllable switch and a twelfth resistor;
the control end of the second controllable switch is connected with a second control signal, the first end of the second controllable switch is respectively connected with the amplification module and the first end of the secondary coil of the transformer, the second end of the second controllable switch is connected with the second end of the secondary coil of the transformer, the third end of the second controllable switch is connected with the first end of the twelfth resistor, and the second end of the twelfth resistor is grounded; the second controllable switch is used for controlling the second end of the second controllable switch to be connected with the first end of the second controllable switch or the third end of the second controllable switch according to the second control signal;
the second controllable switch is used for controlling the output of the signal of the transformer.
In order to solve the technical problem, the invention further provides a myoelectricity collecting instrument which comprises the signal collecting device and a single chip microcomputer, wherein the single chip microcomputer is used for outputting a first control signal and a second control signal to the signal collecting device.
The application provides a signal acquisition device and a myoelectricity acquisition instrument, which are applied to the field of signal acquisition, wherein a differential amplification module is used for carrying out differential amplification on an acquired myoelectricity signal of a user; the isolation module is connected with the differential amplification module and is used for isolating the user from the rear-stage circuit; and the amplifying module is connected with the isolating module and is used for amplifying and outputting the electromyographic signals. The differential amplification module performs differential amplification on the electromyographic signals, so that the interference-free capacity of the signals is higher, the isolation module isolates a user from a rear-stage circuit, the use safety is improved, and the amplification module amplifies weak electromyographic signals so as to process the electromyographic signals in the following process.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed in the prior art and the embodiments will be briefly described 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 without creative efforts.
Fig. 1 is a schematic structural diagram of a signal acquisition device according to the present invention;
FIG. 2 is a schematic structural diagram of another signal acquisition device provided by the present invention;
fig. 3 is a schematic structural diagram of a myoelectricity collecting instrument provided by the invention.
Detailed Description
The core of the invention is to provide a signal acquisition device and a myoelectric acquisition instrument, which have stronger interference-free capability of signals, improve the use safety of the signal acquisition device and facilitate the subsequent processing of myoelectric signals.
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. 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 invention.
Fig. 1 is a schematic structural diagram of a signal acquisition device provided in the present invention, the signal acquisition device includes:
the differential amplification module 1 is used for carrying out differential amplification on the collected electromyographic signals of the user;
the isolation module 2 is connected with the differential amplification module 1 and is used for isolating a user from a rear-stage circuit;
and the amplifying module 3 is connected with the isolating module 2 and is used for amplifying and outputting the electromyographic signals.
The electromyographic signals are the superposition of action potentials of motor units in a plurality of muscle fibers in time and space. The surface electromyographic signals are the comprehensive effect of the electrical activity of superficial muscles and nerve trunks on the surface of the skin and can reflect the activity of the neuromuscular to a certain extent; the electromyographic signals have the advantages of non-invasiveness, no wound, simplicity in operation and the like in measurement. Therefore, the electromyographic signals have important practical values in clinical medicine, human-computer efficiency, rehabilitation medicine, sports science and the like. However, the myoelectric signals on the surface of the human body are weak and are easily interfered, so that the myoelectric signals are difficult to acquire.
Considering that the electromyographic signals are weak and not easy to collect, the application provides a signal collecting device, which comprises a differential amplification module 1, an isolation module 2 and an amplification module 3, wherein the differential amplification module 1 is used for carrying out differential amplification on the electromyographic signals, and the differential signals have the advantages of being capable of easily identifying small signals, achieving high immunity through external electromagnetic interference, better processing bipolar signals and the like, so that the weak electromyographic signals are more stable and are not interfered.
Considering that the signal acquisition device comprises various circuits, the electrode plate is pasted on the user, and the user may be damaged in the process of acquiring the electromyographic signals if no isolation measure is taken, an isolation module 2 is needed to isolate the user from the rear-stage circuit.
Considering that the electromyographic signals are weak, the electromyographic signals are timely collected and are not convenient for subsequent processing, the amplification module 3 is provided in the application, the electromyographic signals are amplified, and other processing can be conveniently performed according to the electromyographic signals subsequently.
In summary, the present application provides a signal acquisition apparatus, which is applied to the field of signal acquisition, and the differential amplification module 1 is configured to differentially amplify an acquired electromyographic signal of a user; the isolation module 2 is connected with the differential amplification module 1 and is used for isolating a user from a rear-stage circuit; and the amplifying module 3 is connected with the isolating module 2 and is used for amplifying and outputting the electromyographic signals. The differential amplification module 1 performs differential amplification on the electromyographic signals, so that the interference-free capacity of the signals is higher, the isolation module 2 isolates a user from a rear-stage circuit, the use safety is improved, and the amplification module 3 amplifies weak electromyographic signals so as to process the electromyographic signals in the following process.
On the basis of the above-described embodiment:
FIG. 2 is a schematic structural diagram of another signal acquisition device provided by the present invention;
as a preferred embodiment, the differential amplification module 1 includes an input impedance matching module and the differential amplification module 1, where the input impedance matching module is connected to the differential amplification module 1;
the input impedance matching module is used for carrying out impedance matching on the collected electromyographic signals of the user and the differential amplification module 1;
the differential amplification module 1 is used for performing differential amplification on the electromyographic signals of the user.
TP1 is the positive end of the myoelectric signal, TP2 is the negative end of the myoelectric signal.
Considering that the electromyographic signal needs to meet the design requirement of input impedance, an impedance matching module is arranged to perform impedance matching on the electromyographic signal and the differential amplification module 1.
In addition, considering that the amplification effect is general when one amplification module 3 is used for amplifying signals, the myoelectric signals are amplified at each stage, so that the working pressure of the last stage of amplification is reduced.
As a preferred embodiment, the input impedance matching module includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a first capacitor C1, and a second capacitor C2;
a first end of a first resistor R1 and a first end of a first capacitor C1 are both connected with the anode of the electromyographic signal, a second end of a first resistor R1 is connected with a first end of a second resistor R2, a second end of the second resistor R2 is respectively connected with a first end of a third resistor R3 and a first end of a fourth resistor R4, a second end of the first capacitor C1 is respectively connected with a second end of the third resistor R3 and a second end of a second capacitor C2, a second end of the fourth resistor R4 is connected with a first end of a fifth resistor R5, and a second end of the fifth resistor R5 is respectively connected with a second end of the second capacitor C2 and the cathode of the electromyographic signal;
the first resistor R1 and the first capacitor C1 are used for filtering signals input by the positive pole of the electromyographic signals, the fifth resistor R5 and the second capacitor C2 are used for filtering signals input by the negative pole of the electromyographic signals, the second resistor R2 and the fourth resistor R4 are used for impedance matching, and the third resistor R3 is used for eliminating noise.
Considering that the electromyographic signal may have noise, a first resistor R1 and a first capacitor C1 are provided to filter the signal inputted from the positive pole of the electromyographic signal, a fifth resistor R5 and a second capacitor C2 are provided to filter the signal inputted from the negative pole of the electromyographic signal, and considering that the electromyographic signal may have partial noise, a third resistor R3 is provided to eliminate the noise in the signal.
The electromyographic signal is more accurate through the first resistor R1, the second resistor R2, the third resistor R3, the fourth resistor R4, the fifth resistor R5, the first capacitor C1 and the second capacitor C2, and subsequent processing is facilitated.
As a preferred embodiment, the differential amplification module 1 includes a first operational amplifier U1, a second operational amplifier U2, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8 and a ninth resistor R9;
the positive electrode of the electromyographic signal is connected with the positive phase input end of the first operational amplifier, the output end of the first operational amplifier is connected with the first end of the sixth resistor, the connected common end is used as the first output end of the differential amplification module 1, the second end of the sixth resistor is respectively connected with the inverting input end of the first operational amplifier and the first end of the seventh resistor, and the second end of the seventh resistor is grounded;
the negative electrode of the electromyographic signal is connected with the positive phase input end of the second operational amplifier, the output end of the second operational amplifier is connected with the first end of the eighth resistor, the connected common end of the output end of the second operational amplifier and the first end of the eighth resistor serves as the second output end of the differential amplification module 1, the second end of the eighth resistor is respectively connected with the inverting input end of the second operational amplifier and the first end of the ninth resistor, and the second end of the ninth resistor is grounded;
the first operational amplifier is used for amplifying the signals input by the positive pole of the electromyographic signals, and the second operational amplifier is used for amplifying the signals input by the negative pole of the electromyographic signals.
The voltage of the positive phase input end of the first operational amplifier is UA, the voltage of the negative phase input end of the first operational amplifier is UB, the voltage of the positive phase input end of the second operational amplifier is UC, the voltage of the negative phase input end of the second operational amplifier is UD, the voltage of the output end of the first operational amplifier is UE, and the voltage of the output end of the second operational amplifier is UF. According to the virtual short of the operational amplifier, UA equals UB and UC equals UD.
For AC signals, according to the virtual break of the operational amplifier, then
(UE-UB)/R6＝UB/R7 (I)
(UF-UC)/R8＝UC/R9 (II)
The in-circuit resistor R6 is R8, and R7 is R9;
subtracting formula (II) from formula (I);
【(UE-UB)-(UF-UC))】/R6＝(UB-UC)/R7；
the above formula is converted into [ UE-UF) - (UB-UC ]/R6 ═ UB-UC)/R7;
since R6 is much larger than R7 during the design of the circuit;
(UE-UF)/R6＝(UB-UC)/R7；
the fractional transformation is (UE-UF)/(UB-UC) ═ R6/R7;
UE-UF＝(UB-UC)R6/R7。
the final magnification is determined by the resistances of R6 and R7.
And a Porro capacitor C5 connected to the power supply for filtering.
As a preferred embodiment, the voltage difference amplifying module further comprises a feedback module, and the feedback module is configured to amplify a median of the voltages output by the difference amplifying module 1 in an opposite phase and output the amplified median to a user.
It is considered that the common mode signal is doped in the signal collected from the human body. The median of the voltage output by the differential amplification module 1 is taken, is subjected to inverse amplification and is connected to a reference point, so that the common mode noise can be effectively eliminated.
It should be noted that the electrode sheet is connected with the user at three point locations, two point locations being collection points, and one point location being a reference point.
The output of the differential amplification module 1 is also connected with a capacitor C9 in parallel for filtering, and the filtered signal is transmitted to the isolation module 2.
As a preferred embodiment, the feedback module includes a tenth resistor R10, an eleventh resistor R11 and a third operational amplifier U3, a first end of the tenth resistor R10 is connected to the positive phase output terminal of the differential amplification module 1, a second end of the eleventh resistor R11 is connected to the negative phase output terminal of the differential amplification module 1, a second end of the tenth resistor R10 and a second end of the eleventh resistor R11 are connected to the negative phase input terminal of the third operational amplifier U3, the positive phase input terminal of the third operational amplifier U3 is grounded, and the output terminal of the third operational amplifier U3 is connected to the user;
the resistance values of the tenth resistor R10 and the eleventh resistor R11 are equal, and the tenth resistor R10 and the eleventh resistor R11 are used for collecting the median value of the voltage output by the differential amplification module 1; the third operational amplifier U3 is used to amplify the median value and output it to the user.
Since the tenth resistor R10 and the eleventh resistor R11 have the same resistance, the voltage at the common end where the tenth resistor R10 and the eleventh resistor R11 are connected is the median of the voltages output by the differential amplifier module 1.
The voltage stabilizer also comprises an operational amplifier U4, wherein a common end of the connection of the R10 and the R11 is connected with a non-inverting input end of U4, an inverting input end of U4 is connected with an output end of U4, U4 is used as a voltage follower, an output end of U4 is connected with an inverting input end of U3, and stable voltage is input into U3. The first terminal of the capacitor C20 is connected to the non-inverting input terminal of U4, and the second terminal of C20 is connected to ground for filtering.
The feedback module further comprises resistors R21, R24, R25, R26, capacitors C18, C19, C21, C23 and C24, and the amplification effect is achieved by combining the resistors with U3.
TP4 is the reference terminal of the electromyographic signal. TP1, TP2 and TP4 are connected to electrode pads attached to the user.
As a preferred embodiment, the power frequency interference suppression device further comprises a filtering module connected to the amplifying module 3, and the filtering module is configured to filter power frequency interference of a preset frequency.
Specifically, the filtering module is composed of resistors R15, R16, R19, R20, R23, R27, capacitors C8, C12, C15, C22 and a slide rheostat AR1, and is used for filtering interference of fixed power frequency, so that output signals are more accurate.
Specifically, the fixed power frequency is 50Hz, the TP3 is connected with a single chip microcomputer, and the single chip microcomputer is used for processing signals.
It should be noted that the amplifying module 3 includes resistors R14, R22, capacitors C7, C14, C16, and an operational amplifier U6, and amplifies the signal output by the isolating module 2 and outputs the amplified signal to the filtering module.
As a preferred embodiment, the isolation module 2 includes a first controllable switch U7 and a transformer L1;
the control end of the first controllable switch U7 is connected with a first control signal, the first end of the first controllable switch U7 is respectively connected with the positive output end of the differential amplification module 1 and the first end of the primary coil of the transformer L1, the second end of the first controllable switch U7 is connected with the second end of the primary coil of the transformer L1, and the third end of the first controllable switch U7 is connected with the negative output end of the differential amplification module 1; the first controllable switch U7 is used for controlling the second terminal of the first controllable switch U7 to be connected with the first terminal of the first controllable switch U7 or the third terminal of the first controllable switch U7 according to the first control signal IN 1;
a first end of the secondary coil of the transformer L1 is connected to the amplifying module 3, a second end of the secondary coil of the transformer L1 is grounded, and the transformer L1L1 is configured to amplify the signal output by the differential amplifying module 1 and output the amplified signal to the amplifying module 3.
It should be noted that when the second end of the U7 is connected to the first end, the primary coil of the transformer L1 has no input, and no electromyographic signal is collected at this time, and when the second end of the U7 is connected to the third end, the primary coil of the transformer L1 has an input, and an electromyographic signal is collected at this time.
The isolation module 3 further includes resistors R13, R17, capacitors C6 and C13 for assisting the U7.
As a preferred embodiment, the isolation module 2 further includes a second controllable switch U8 and a twelfth resistor R12;
a control end of the second controllable switch U8 is connected to a second control signal, a first end of the second controllable switch U8 is connected to the first ends of the amplification module 3 and the secondary coil of the transformer L1, a second end of the second controllable switch U8 is connected to a second end of the secondary coil of the transformer L1, a third end of the second controllable switch U8 is connected to a first end of a twelfth resistor R12, and a second end of the twelfth resistor R12 is grounded; the second controllable switch U8 is used for controlling the second terminal of the second controllable switch U8 to be connected with the first terminal of the second controllable switch U8 or the third terminal of the second controllable switch U8 according to a second control signal IN 2;
the second controllable switch U8 is used to control the output of the signal of transformer L1.
When the second terminal and the first terminal of U8 are connected, the secondary winding of transformer L1 has an output, and when the second terminal and the third terminal of U8 are connected, the secondary winding of transformer L1 has no output.
The isolation module 3 further includes resistors R14 and R18, capacitors C3, C4, and C17 for assisting U8.
Fig. 3 is a schematic structural diagram of the myoelectricity collecting instrument provided by the invention, which includes the signal collecting device and further includes a single chip microcomputer 4, wherein the single chip microcomputer 4 is used for outputting a first control signal IN1 and a second control signal IN2 to the signal collecting device.
Please refer to the above embodiments for the introduction of the myoelectric collecting instrument provided by the present application, which is not described herein again.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.
It is further noted that, in the present specification, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. A signal acquisition device, comprising:
the differential amplification module is used for carrying out differential amplification on the collected electromyographic signals of the user;
the isolation module is connected with the differential amplification module and is used for isolating a user from a rear-stage circuit;
and the amplifying module is connected with the isolating module and is used for amplifying and outputting the electromyographic signals.
2. The signal acquisition device according to claim 1, wherein the differential amplification module comprises an input impedance matching module and a differential amplification module, and the input impedance matching module is connected with the differential amplification module;
the input impedance matching module is used for performing impedance matching on the collected electromyographic signals of the user and the differential amplification module;
the differential amplification module is used for carrying out differential amplification on the electromyographic signals of the user.
3. The signal acquisition device of claim 2 wherein the input impedance matching module comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a first capacitor, and a second capacitor;
a first end of the first resistor and a first end of the first capacitor are both connected with the anode of the electromyographic signal, a second end of the first resistor is connected with a first end of the second resistor, a second end of the second resistor is respectively connected with a first end of the third resistor and a first end of the fourth resistor, a second end of the first capacitor is respectively connected with a second end of the third resistor and a second end of the second capacitor, a second end of the fourth resistor is connected with a first end of the fifth resistor, and a second end of the fifth resistor is respectively connected with a second end of the second capacitor and the cathode of the electromyographic signal;
the first resistor and the first capacitor are used for filtering signals input by the positive pole of the electromyographic signals, the fifth resistor and the second capacitor are used for filtering signals input by the negative pole of the electromyographic signals, the second resistor and the fourth resistor are used for impedance matching, and the third resistor is used for eliminating noise.
4. The signal acquisition device according to claim 2, wherein the differential amplification module comprises a first operational amplifier, a second operational amplifier, a sixth resistor, a seventh resistor, an eighth resistor, and a ninth resistor;
the positive electrode of the electromyographic signal is connected with the positive phase input end of the first operational amplifier, the output end of the first operational amplifier is connected with the first end of the sixth resistor, the connected common end of the first operational amplifier and the first end of the sixth resistor serves as the first output end of the differential amplification module, the second end of the sixth resistor is respectively connected with the inverting input end of the first operational amplifier and the first end of the seventh resistor, and the second end of the seventh resistor is grounded;
the negative electrode of the electromyographic signal is connected with the positive phase input end of the second operational amplifier, the output end of the second operational amplifier is connected with the first end of the eighth resistor, and the connected common end serves as the second output end of the differential amplification module;
the first operational amplifier is used for amplifying a signal input by the positive pole of the electromyographic signal, and the second operational amplifier is used for amplifying a signal input by the negative pole of the electromyographic signal.
5. The signal acquisition device according to claim 1, further comprising a feedback module, wherein the feedback module is configured to perform inverse amplification on the median of the voltage output by the differential amplification module and output the amplified voltage to the user.
6. The signal acquisition device according to claim 5, wherein the feedback module comprises a tenth resistor, an eleventh resistor and a third operational amplifier, a first end of the tenth resistor is connected to the positive-phase output terminal of the differential amplification module, a second end of the eleventh resistor is connected to the negative-phase output terminal of the differential amplification module, a second end of the tenth resistor and a second end of the eleventh resistor are connected to the negative-phase input terminal of the third operational amplifier, the positive-phase input terminal of the third operational amplifier is grounded, and the output terminal of the third operational amplifier is connected to the user;
the tenth resistor and the eleventh resistor have the same resistance value and are used for collecting a median value of the voltage output by the differential amplification module; and the third operational amplifier is used for amplifying the median value and outputting the amplified median value to the user.
7. The signal acquisition device according to claim 1, further comprising a filtering module connected to the amplifying module, wherein the filtering module is configured to filter power frequency interference at a predetermined frequency.
8. The signal acquisition device of any one of claims 1 to 7 wherein the isolation module comprises a first controllable switch and a transformer;
the control end of the first controllable switch is connected with a first control signal, the first end of the first controllable switch is respectively connected with the output positive end of the differential amplification module and the first end of the primary coil of the transformer, the second end of the first controllable switch is connected with the second end of the primary coil of the transformer, and the third end of the first controllable switch is connected with the output negative end of the differential amplification module; the first controllable switch is used for controlling the second end of the first controllable switch to be connected with the first end of the first controllable switch or the third end of the first controllable switch according to the first control signal;
the first end of the secondary coil of the transformer is connected with the amplifying module, the second end of the secondary coil of the transformer is grounded, and the transformer is used for amplifying the signal output by the differential amplifying module and then outputting the amplified signal to the amplifying module.
9. The signal acquisition device of claim 8 wherein the isolation module further comprises a second controllable switch and a twelfth resistor;
the control end of the second controllable switch is connected with a second control signal, the first end of the second controllable switch is respectively connected with the amplification module and the first end of the secondary coil of the transformer, the second end of the second controllable switch is connected with the second end of the secondary coil of the transformer, the third end of the second controllable switch is connected with the first end of the twelfth resistor, and the second end of the twelfth resistor is grounded; the second controllable switch is used for controlling the second end of the second controllable switch to be connected with the first end of the second controllable switch or the third end of the second controllable switch according to the second control signal;
the second controllable switch is used for controlling the output of the signal of the transformer.
10. An electromyography acquisition instrument, comprising the signal acquisition device of any one of claims 1 to 9, and further comprising a single chip microcomputer, wherein the single chip microcomputer is used for outputting a first control signal and a second control signal to the signal acquisition device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210884663.9A CN115105102A (en) | 2022-07-25 | 2022-07-25 | Signal acquisition device and myoelectricity acquisition instrument |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210884663.9A CN115105102A (en) | 2022-07-25 | 2022-07-25 | Signal acquisition device and myoelectricity acquisition instrument |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115105102A true CN115105102A (en) | 2022-09-27 |
Family
ID=83335145
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210884663.9A Pending CN115105102A (en) | 2022-07-25 | 2022-07-25 | Signal acquisition device and myoelectricity acquisition instrument |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115105102A (en) |
-
2022
- 2022-07-25 CN CN202210884663.9A patent/CN115105102A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106419894B (en) | One kind acquiring front-end processing circuit for electro-physiological signals | |
| WO2012102880A1 (en) | Apparatus and method for amplification with high front-end gain in the presence of large dc offsets | |
| CN104799854A (en) | Surface myoelectricity acquisition device and myoelectricity signal processing method thereof | |
| CN104757964B (en) | The superelevation common mode rejection circuit and electrocardiogram acquisition equipment of ecg signal acquiring | |
| CN112617866A (en) | EMG (electromagnetic EMG) electromyographic signal digital acquisition circuit and system | |
| CN104783781B (en) | Low distortion ecg signal acquiring process circuit and electrocardiogram acquisition equipment | |
| Djermanova et al. | LabVIEW based ECG signal acquisition and analysis | |
| CN110772232B (en) | Electrode falling detection circuit and detection method | |
| CN103705230B (en) | Pre-stage circuit in bioelectricity detection | |
| WO2024109038A1 (en) | Device for acquiring electroencephalogram signal by means of electric potential | |
| CN218165273U (en) | Signal acquisition device and myoelectricity acquisition instrument | |
| CN115105102A (en) | Signal acquisition device and myoelectricity acquisition instrument | |
| KR101048567B1 (en) | Apparatus for measurement the voltage which occurs in from subject | |
| CN205083477U (en) | Real time control device based on body surface flesh | |
| Bansal | Design of 50 Hz notch filter circuits for better detection of online ECG | |
| CN116458890A (en) | Surface electromyographic signal output circuit and acquisition equipment | |
| CN216876378U (en) | Physiological electric signal acquisition system | |
| CN209826722U (en) | Surface electromyogram signal acquisition device | |
| Fu et al. | Optimizing surface electromyography acquisition without right leg drive circuit | |
| CN209236145U (en) | A kind of hand-held myoelectricity acquisition device | |
| CN114732412A (en) | Electroencephalogram signal detection equipment | |
| CN217510496U (en) | Small signal acquisition circuit | |
| Kumar et al. | Design and development of low-cost eog acquisition circuit for hmi application | |
| JP2014023711A (en) | Skin electric activity measuring device | |
| CN209499724U (en) | A kind of portable mobile wireless ECG monitoring device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |