TWI459929B - Real-time monitoring apparatus for volitional and stimulated muscle force - Google Patents

Description

Instant autonomic muscle strength and electrical stimulation-induced muscle strength measurement circuit

The invention relates to an instant signal processing and analysis circuit and method, in particular to an instant autonomic and electrical stimulation muscle force detecting circuit and method for integrating an electrical stimulator and a myoelectric signal amplifier.

From the myoelectric signal map, the state and output of the target muscles currently observed can be analyzed. However, since the myoelectric signal is the receiving electrical signal, and the electrical stimulator transmits the electrical signal, wherein the stimulation signal is much larger than the myoelectric signal, it is necessary to be able to analyze the myoelectric signal while receiving the electrical stimulation, which requires special signal processing, but currently There are no monitors that implement this method on the fly.

It is illustrated by the following example: In the prior art 1 (Republic of China patent number: TWI318872), the myoelectric signal is a small signal, so it is necessary to amplify through an amplifier. However, because of the amplification of the electronic circuit, the myoelectric signal is easily affected by other electrical signals, and it is impossible to observe and study the target muscle under electrical stimulation.

Another prior art 2 (U.S. Patent No.: US 722, 1980) is an electrical signal feedback technique that extracts the myoelectric signal of a non-target muscle, and then calculates and judges the signal as a control signal to control the electrical stimulator pair. The target signal is stimulated, but in this way, the myoelectric signal under the electrical stimulation cannot be directly observed, and the result is not accurate.

In summary, it is known that the existing techniques cannot simultaneously and instantly detect the autonomic muscle signals and stimulation-induced EMG signals of the muscles of the electrical stimulation, and cannot directly analyze and detect the target muscles.

Based on the above problems of the prior art, the present invention provides an innovative technique and method capable of immediately extracting electrical stimulation-induced myoelectric signals and autonomous electromechanical signals while the muscles are electrically stimulated.

In order to solve the problem that the prior art cannot simultaneously obtain the signals of the myoelectric signal and the electrical stimulator, and the technical problem that the target muscle can not be directly observed and analyzed, the present invention provides an instant extraction stimulus capable of performing electrical stimulation on the muscle. Induced EMG signals and autonomous EMG signals, which can instantly monitor stimulated EMG signals and can be used in electrical stimulation aids and therapeutic devices.

In order to solve the foregoing technical problems, the present invention provides a real-time muscle strength and electrical stimulation-induced muscle strength measuring circuit, comprising: an integrated instant electrical stimulation electromyography signal processing unit that receives external electrical stimulation parameter settings; an electrical stimulation The device is connected to the integrated instant electrical stimulation electromyography processing unit and subjected to the control of the integrated instant electrical stimulation electromyography processing unit to electrically stimulate a user; a myoelectric signal having a stimulation interference suppressor An amplifier that measures the mixed myoelectric signal of the user and removes the stimulus to amplify the signal; an analog-to-digital conversion unit connected to the myoelectric signal amplifier with the stimulus interference suppressor and the integrated instant electrical stimulation muscle Between the electrical signal processing units, the output signal of the myoelectric signal amplifier having the stimulation interference suppressor is digitized; wherein the integrated instant electrical stimulation electromyography processing unit digitizes the mixed myoelectric signal according to the digitization The order is comb-filtered to produce a boundary effect, and after removing the boundary effect, an autonomous muscle signal is generated; Generating a subtraction mode evoked EMG signal.

The integrated instant stimulation electromyography processing unit comprises: a control unit for receiving external electrical stimulation parameter settings; and a signal processing unit for receiving the mixed muscle telecommunications output by the analog digital conversion unit a peak-to-peak detector, which is connected to the signal processing unit; a wave-blocking operator connected to the signal processing unit; an output interface connected to the signal processing unit and the peak-to-peak detection The detector and the wave seal operator are connected, and output signals of the signal processing unit, the peak-to-peak detector, and the wave seal operator.

The signal processing unit further includes: a comb filter connected to the analog digital conversion unit, and after receiving the mixed muscle electrical signal, combing the mixed myoelectric signal to filter the mixed muscle electrical signal Forming an autonomous muscle signal with a boundary effect; a boundary effect shutter coupled to the comb filter to mask the boundary effect of the autonomous muscle signal containing the boundary effect to generate an autonomous muscle signal; The subtractor outputs the stimulation-induced myoelectric signal by subtracting the mixed myoelectric signal and the autonomous myoelectric signal.

Wherein, the peak calculates and outputs a peak-to-peak value of the stimulation-induced EMG signal to the peak detector.

Wherein, the wave seal operator is a low pass filter or an electronic component that performs an average calculation.

Therefore, the present invention can effectively monitor the electromyographic signal of the myoelectric signal, the autonomous myoelectric signal and the electrical stimulation-induced myoelectric signal, so that the medical and detection processes are not only simple, but also can directly observe certain parts. The myoelectric signal makes the test result more accurate and direct.

As shown in FIG. 1 , it is an embodiment of a real-time muscle strength and electrical stimulation-induced muscle strength measuring circuit, and the instant autonomous muscle force and electrical stimulation-induced muscle strength measuring circuit comprises an integrated instant electrical stimulation electromyography signal processing unit. (10), an electrical stimulator (11), a myoelectric signal amplifier (13) having a stimulus interference suppressor, and an analog-to-digital conversion unit (14). The electrical stimulator (11) is connected between the integrated instant electrical stimulation electromyography processing unit (10) and a user (12), and the electrical stimulator (11) is subjected to the integrated instant electrical stimulation electromyographic signal The control unit (10) controls the user to output an electrical stimulation signal; the electromyographic signal amplifier (13) having the stimulation interference suppressor is connected in series with the analog digital conversion unit (14) and then connected to the integrated instant electrical stimulation muscle The electrical signal processing unit (10), wherein the myoelectric signal amplifier (13) having the stimulation interference suppressor measures the user (12) to be transmitted by the mixed electromyography signal of the electrical stimulator (11) to The integrated instant electrical stimulation electromyography processing unit (10), wherein the mixed myoelectric signal comprises the electrical stimulation signal and one of the muscle electrical signals reflected by the user (12).

After the integrated instant electrical stimulation electromyography processing unit (10) receives the setting of an external electrical stimulation parameter, the electrical stimulator (11) is controlled to output the electrical stimulation signal to the user (12) for electrical stimulation. At the same time, the myoelectric signal amplifier (13) with the stimulation interference suppressor immediately measures the mixed myoelectric signal of the user (12), and the myoelectric signal amplifier (13) with the stimulation interference suppressor will electrically stimulate The mixed muscle electrical signal during the auxiliary action removes the interference of the electrical stimulation signal and amplifies it, and then sends it to the analog digital conversion unit (14) for conversion into a digital signal. Then, the integrated instant electrical stimulation myoelectric signal processing unit (10) processes the received signal and outputs an output signal, wherein the output signal comprises a stimulus-induced myoelectric signal, an autonomous myoelectric signal, and a stimulus. The peak-to-peak value of the myoelectric signal and the autonomous myoelectric signal in the form of a wave seal. In the application of various signals, taking an electric stimulation assisted treading system as an example, the muscle contraction during the electric stimulation assisted treading is caused by the autonomous (contracted) myoelectric signal and the external electrical stimulation (ie, the stimulation-induced EMG signal). Produced by two different sources, such muscle activation can be considered as mixed muscle activation. Since the stimulation-induced EMG signal is generated with each pulse of the electrical stimulation signal, the stimulation-induced EMG signal is a signal having the same frequency as the electrical stimulation pulse. The characteristics of the autonomic muscle signal are consistent with the peak shape of the general physiological myoelectric signal. Based on the foregoing, the isolated stimulation-induced myoelectric signal and the autonomous myoelectric signal can respectively indicate the force caused by the user's electrical stimulation and the residual action ability of the patient to step on the electrical stimulation to assist the treadmill.

In the technique of signal separation, the stimulation induces a characteristic of a fixed frequency of the myoelectric signal, so that the stimulation-induced EMG filter can be used as long as the comb-like filter can be used to recognize the signal having the specific characteristic waveform to be taken out. The autonomous myoelectric signal is obtained at the same time (signal subtraction). When the autonomous myoelectric signal is obtained, the stimulation-induced myoelectric signal can be obtained by subtracting the autonomous myoelectric signal from the mixed myoelectric signal. The comb filter is a kind of digital filter. The characteristic of the digital filter is to calculate a signal data point (time tx) and other earlier data points (time tx-n) to filter out the fixed frequency. The signal is filtered and the data points are filtered, so the stimulation-induced EMG signal can be filtered out and the autonomic muscle signal can be obtained by using a comb filter.

The above-mentioned electrical stimulation signal and myoelectric signal are as follows: the electrical stimulation signal is substantially a pulse wave type electrical signal; the myoelectric signal is also a kind of electrical signal; and for the electrical signals, the human body is visible It is a circuit composed of a resistor and a capacitor connected in series and in parallel. Therefore, when each pulse form of the electrical signal hits the human target, the muscle will be charged and discharged, and the myoelectric signal is a very small signal compared to the charge and discharge caused by the electrical stimulation pulse ( Approximately 1000:1), so the pulse of the electrical stimulation signal is measured by the myoelectric signal as a large interference. In terms of removing the aforementioned interference signal, since the time point of the pulse of the electrical stimulation signal is known to the present embodiment, the integrated immediate electrical stimulation myoelectric signal processing unit (10) is only required to pulse the electrical stimulation signal. At the same time, the positive and negative inputs of the myoelectric signal amplifier (13) with the stimulation interference suppressor are short-circuited, thereby causing a short zero input to remove the interference of the electrical stimulation signal. In addition, since the pulse width of the pulse of the electrical stimulation signal is very short (about 0.2 milliseconds to about 1 millisecond), the short interruption caused by the short circuit does not have a great influence on the measurement of the myoelectric signal.

Further, referring to FIG. 2, the integrated instant stimulation electromyography processing unit (10) further includes a control unit (101), a signal processing unit (102), and a peak-to-peak detector (103). a wave-blocking operator (104) and an output interface (105), wherein the control unit (101) is electrically connected to the electrical stimulator (11) and the signal processing unit (102); the peak-to-peak detection The device (103) and the wave seal operator (104) are respectively connected between the signal processing unit (102) and the output interface (105). After the control unit (101) receives the external electrical stimulation parameter setting, the electrical stimulator (11) is controlled to electrically stimulate the user (12); and the signal processing unit (102) receives the mixed muscle communication The number is calculated and the stimulation-induced myoelectric signal and the autonomous myoelectric signal are calculated. The signal processing unit (102) transmits the stimulus-induced myoelectric signal to the peak-to-peak detector (103) to calculate a peak-to-peak value of the stimulus-induced myoelectric signal; the autonomous muscle signal is transmitted to the wave The sealing operator (104) calculates the autonomous muscle electrical signal in the form of the wave seal; the output interface (105) combines the original mixed myoelectric signal, the stimulus-induced myoelectric signal, the autonomous myoelectric signal, and the stimulus-induced myoelectric signal. The peak-to-peak, wave-sealed form of autonomic muscle signal output for analysis and application. In terms of application, taking the rehabilitation of a patient with a stroke as an example, the physical function damage of the patient affects the movement and quality of life of daily life. In order to enhance some of the residual motion of the patient, the aforementioned use of an electric stimulator in combination with bicycle motion has been used as a rehabilitation technique. In this embodiment, the patient's muscle condition can be measured when the patient uses the electric stimulation to step on the vehicle, so if the signal of the electrical stimulation can be accurately analyzed, the patient's rehabilitation status can be evaluated, and even a more appropriate complex can be planned. Construction process.

With further reference to FIG. 3, the signal processing unit (102) includes a comb filter (201), a boundary effect shutter (202), and a subtractor (203). The comb filter (201) is connected to the signal processing unit (102). After the boundary effect shutter (202), the output interface (105) is connected. The mixed myoelectric signal calculates an autonomous muscle signal containing a boundary effect through the comb filter (201), and then the boundary muscle effect is blocked by the boundary effector (202). Get the autonomic muscle signal. The comb filter (201) is a kind of digital filter, and is characterized in that a signal data point (time t _x ) is operated with other earlier data points (time t _xn ) to obtain a filtered data point; Therefore, the signal a of the equivalent measurement suddenly increases a certain signal b at time t _b , and the data point before t _b does not include the b signal, so that the first period of the signal b cannot be filtered out, the signal b The part that cannot be filtered out is the boundary effect. If the autonomous myoelectric signal is the signal a to be measured, the electrical stimulation-induced myoelectric signal is equivalent to a signal b, which cannot be completely filtered by the comb filter (201). It can be seen that when the electrical stimulation has an action of starting and closing, a boundary effect occurs, but the activation and deactivation of the electrical stimulation is controlled by the integrated instant electrical stimulation electromyography processing unit 10, so the boundary effect occurs. Predictable, so know that you want to zero the signal when the boundary effect occurs. The wave seal operator can be implemented as a low pass filter or an average operation.

The input end of the subtractor (203) is connected to the analog digital conversion unit (14) and the boundary effect masker (202), and the mixed muscle electrical signal reduces the component of the autonomous muscle electrical signal by the subtractor (203). Go to get the stimulus-induced EMG signal; the signal processing unit will output the mixed myoelectric signal, the autonomous myoelectric signal, and the stimulus-induced EMG signal for analysis and application.

10. . . Integrated instant electrical stimulation EMG signal processing unit

11. . . Electric stimulator

12. . . user

13. . . EMG amplifier with stimulus interference suppressor

14. . . Analog digital conversion unit

101. . . control unit

102. . . Signal processing unit

103. . . Peak-to-peak detector

104. . . Wave seal operator

105. . . Output interface

201. . . Comb filter

202. . . Boundary effect shutter

203. . . Subtractor

Figure 1 is a diagram of the instant autonomic muscle strength and electrical stimulation evoked muscle strength measuring circuit of the present invention

2 is an integrated instant electric stimulation electromyography processing unit of the present invention

3 is a schematic diagram of a signal processing unit of the present invention

10. . . Integrated instant electrical stimulation EMG signal processing unit

11. . . Electric stimulator

12. . . user

13. . . EMG amplifier with stimulus interference suppressor

14. . . Analog digital conversion unit

Claims (5)

A real-time muscle strength and electrical stimulation-induced muscle strength measuring circuit, comprising: an integrated instant electrical stimulation myoelectric signal processing unit, which receives an external electrical stimulation parameter setting; an electrical stimulator, and the integrated instant power The stimulation electromyography processing unit is connected and receives the control of the integrated instant electrical stimulation electromyography processing unit to electrically stimulate a user; a myoelectric signal amplifier having a stimulation interference suppressor, which measures the user Mixing the myoelectric signal and removing the stimulus to amplify the signal; an analog-to-digital conversion unit connected between the myoelectric signal amplifier having the stimulus interference suppressor and the integrated instant electrical stimulation electromyographic signal processing unit The output signal of the myoelectric signal amplifier with the stimulation interference suppressor is digitized; wherein the integrated instant electrical stimulation electromyography processing unit sequentially digitizes the mixed myoelectric signal by comb filtering to generate a boundary effect. After removing the boundary effect, an autonomous muscle electrical signal is generated; and a stimulus-induced myoelectric signal is generated by subtraction. The integrated immediate electrical stimulation electromyography processing unit comprises: a control unit for receiving external electrical stimulation parameters, such as the immediate autonomic muscle strength and electrical stimulation evoked muscle strength measuring circuit described in claim 1 a signal processing unit that receives the mixed myoelectric signal output by the analog-to-digital conversion unit; a peak-to-peak detector that is connected to the signal processing unit; and a wave-blocking operator that is coupled to the signal processing The unit is connected; an output interface is respectively connected to the signal processing unit, the peak-to-peak detector, and the wave seal operator, and the signal processing unit, the peak-to-peak detector, and the wave seal operator are outputted Signal. The instant autonomic muscle strength and electrical stimulation evoked muscle strength measuring circuit according to claim 2, wherein the signal processing unit further comprises: a comb filter connected to the analog digital conversion unit and accepting the mixing After the myoelectric signal, the mixed myoelectric signal is comb-filtered, so that the mixed myoelectric signal forms an autonomous muscle signal containing a boundary effect; a boundary effect shutter is connected to the comb filter, and the shadow is shielded The boundary effect of the autonomic muscle signal containing the boundary effect generates an autonomous muscle electrical signal; and a subtractor that outputs the stimulation-induced myoelectric signal by subtracting the mixed myoelectric signal and the autonomous myoelectric signal. The instant autonomic muscle strength and electrical stimulation evoked muscle strength measuring circuit according to claim 3, wherein the peak-to-peak detector calculates and outputs a peak-to-peak value of the stimulation-induced myoelectric signal. The instant autonomic muscle strength and electrical stimulation evoked muscle strength measuring circuit according to claim 3, wherein the wave sealing operator is a low pass filter or an electronic component that performs an average calculation.