An electronic artificial larynx using control based on facial electromyographic signals

Abstract

The present invention proposes a method and system for controlling the start and stop of vibration of an electronic artificial larynx by using facial electromyographic signals. The sounding of the electronic larynx is controlled by the electromyographic signals generated when the user opens and closes his mouth. The electromyographic acquisition system converts the specially processed facial electromyographic signals into switch signals, which can drive the micro-electric conversion system to generate vibrations. When the lips do not make a sound, the electric power conversion module is controlled to stop working. When the lips make a sound, the electric power conversion module is driven to vibrate to generate the electronic artificial larynx voice after the noise between sounds is eliminated. That is, the electric power conversion module only generates the electronic artificial larynx voice when the user's lips make a sound. When the user's lips do not make a sound and between one sound and the next sound, the electric power conversion module stops working, thereby avoiding the generation of noise. This method can solve the problem of noise interference in the vocalization gap during the vocalization process of the electronic artificial larynx and improve the application effect of the electronic artificial larynx.

Description

Technical Field

[0001] The invention relates to an electronic artificial larynx controlled based on facial electromyographic signals and a vibration phonation start and stop control method thereof, belonging to the field of speech rehabilitation in rehabilitation engineering. Background Art

[0002] As a carrier of language, speech is the most basic, effective and important means of communication for humans. Speech can not only convey language information, but also convey the speaker's personality and emotional information. Domestic and foreign statistics show that there are currently millions of patients with laryngeal cancer and severe laryngeal diseases in the world who have lost their voice and speech functions due to laryngectomy and other reasons. The number of such patients is increasing year by year. They not only experience the pain caused by laryngectomy, but also their quality of life is significantly reduced due to the loss of speech function. These patients can use speech rehabilitation aids to rebuild their speech function.

[0003] The electronic artificial larynx is a speech assistive device and one of the most widely used methods of vocal function reconstruction. The user only needs to press the device against the mandible, and the vibration sound generated by it is transmitted to the oral cavity through the neck tissue, and then modulated by the oral cavity to produce speech at the lips. The electronic artificial larynx has many advantages, such as being easy to use, easy to maintain, and not limited by the patient's laryngeal fistula. In any case, the current electronic artificial larynx still has problems such as monotonous voice, mechanical taste, and high noise, which seriously affects the intelligibility of speech and is significantly different from the normal speech quality. Among them, the radiation noise generated by the electronic artificial larynx itself during the phonation process is one of the important factors affecting speech intelligibility.

[0004] In order to eliminate the self-radiated noise, some noise elimination methods have been proposed. Most of these methods use signal processing technology to process the generated speech. This is a post-processing method and cannot achieve real-time noise elimination during the phonation process. In addition, the previous research results published by the inventors show that the main factor affecting the speech quality of the electronic artificial larynx is the noise between one sound and the next sound. Removing the noise between sounds can improve speech intelligibility.

[0005] The inventor has proposed methods and techniques for improving the intelligibility of electronic larynx in the authorized Chinese patents such as "Finger-pressure fundamental frequency adjustment electronic artificial larynx" (Patent No.: ZL200910090549.3), "Electronic artificial larynx system using roller to adjust vocal fundamental frequency and fundamental frequency adjustment method thereof" (Patent No.: ZL201610270925.7), and "Air pressure fundamental frequency adjustment electronic artificial larynx" (Patent No.: ZL200910090589.8), but these methods are mainly achieved through fundamental frequency adjustment and do not involve noise elimination; the method proposed in the patent "Electronic artificial larynx system with speech conversion function and speech conversion method thereof" (Patent No.: ZL201410377514.9) can eliminate radiated noise by using speech signal processing technology, but this is a post-processing method and cannot be achieved in real time. Summary of the invention

[0006] In view of the defects of the existing electronic artificial larynx in noise elimination, the present invention provides a method and system that can use facial electromyographic signals to control the start and end of the vibration of the electronic artificial larynx, solves the problem of real-time noise elimination during the vocalization process, and improves the intelligibility of the speech.

[0007] According to one aspect of the present invention, there is provided an electronic artificial larynx using control based on facial electromyographic signals, characterized in that it comprises:

[0008] The power module is used to supply power to all parts of the electronic artificial larynx.

[0009] Surface electrodes are used to fit the user's facial skin to obtain myoelectric signals.

[0010] EMG amplifier circuit, used to amplify EMG signals.

[0011] The EMG signal filtering and sampling part filters and digitizes the EMG signal amplified by the EMG amplifier circuit, and provides the digitized EMG signal to the signal processing module.

[0012] The start-stop control part is used to convert the digitized EMG signal provided by the EMG signal filtering and sampling circuit into a start-stop control signal.

[0013] The micro electric-to-force conversion module is used to generate mechanical vibration under the control of the start-stop control signal, thereby producing the speech of the electronic artificial larynx.

[0014] According to another aspect of the present invention, a method and system for controlling the start and stop of vibration of an electronic artificial larynx using facial electromyographic signals are provided, including a power supply module, a facial electromyographic signal acquisition module, an electromyographic signal processing module, and a micro electric-to-force conversion module.

[0015] The design of the micro-electric-force conversion module can refer to the invention patents that the inventor has authorized: "Glottal wave simulation type electronic artificial larynx with personal characteristics" (ZL200910089700.1) and "Finger pressure type fundamental frequency adjustment electronic artificial larynx" (patent number: ZL200910090549.3). It should be pointed out that the present invention is intended to protect the method of controlling the start and end of the vibration of the electronic artificial larynx using facial electromyographic signals, and the micro-electric-force conversion system used in the system does not belong to the specific technical features of the present invention.

[0016] Furthermore, the facial electromyographic signal acquisition module includes surface electrodes, an amplifier circuit, and an electromyographic signal filtering and sampling circuit. The surface electrodes are used to obtain facial electromyographic signals that are closely related to the opening and closing of the lips; the amplifier circuit is used to amplify the electromyographic signals, generally using a two-stage amplification method; the electromyographic signal filtering and sampling circuit is used to filter and digitize the acquired surface electromyographic signals, and then provide the digital signals to the signal processing module.

[0017] Furthermore, the electromyographic signal processing module includes two parts: a microprocessor and a start-stop control circuit. The microprocessor is used to process the acquired digital electromyographic signal, establish a mathematical relationship with the lip opening and closing, and convert the processed electromyographic signal into a start-stop control signal to control the operation of the electronic laryngeal electro-mechanical conversion system.

[0018] According to another aspect of the present invention, there is provided a method for controlling the start and stop of vibration of an electronic artificial larynx using facial electromyographic signals, comprising the following steps:

[0019] Step 1: The user starts to make lip opening and closing movements according to the speaking needs;

[0020] Step 2: The electromyographic signal acquisition module acquires the facial electromyographic signal related to the lip opening and closing action, and the signal is amplified and sent to the signal processing module;

[0021] Step 3: The electromyographic signal processing module converts the electromyographic signal into a vibration start / stop switch control signal and provides it to the start / stop control circuit;

[0022] Step 4: The start-stop control module drives the micro-electric-power conversion system to generate and stop vibration, and generates intermittent electronic artificial laryngeal voice as needed.

[0023] The advantages of the present invention are:

[0024] (1) The present invention helps the user of the electronic artificial larynx to eliminate interstitial noise while the electronic artificial larynx produces speech, thereby improving the intelligibility of the speech.

[0025] (2) The present invention realizes real-time control of the start and end of electronic laryngeal vibration by collecting facial electromyographic signals related to lip opening and closing, thereby realizing automatic elimination of inter-sound noise without the need for training. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The schematic diagram of an electronic artificial laryngeal system for realizing start and stop control based on facial electromyographic signals according to an embodiment of the present invention.

[0027] Figure 2 This is a configuration diagram of an electromyographic signal acquisition module of an electronic artificial larynx that implements start and stop control based on facial electromyographic signals according to an embodiment of the present invention.

[0028] Figure 3 This is a configuration diagram of a signal processing module of an electronic artificial larynx that implements start and stop control based on facial electromyographic signals according to an embodiment of the present invention.

[0029] Figure 4 The figure is a schematic diagram of the appearance of an electronic artificial larynx that realizes start and stop control based on facial electromyographic signals according to an embodiment of the present invention.

[0030] Figure 5 The figure is a schematic diagram of using an electronic artificial larynx to realize start and stop control based on facial electromyographic signals according to an embodiment of the present invention.

[0031] Figure 6 The present invention is a flow chart of a method for noise reduction of an electronic artificial larynx that implements start and stop control based on facial electromyographic signals according to an embodiment of the present invention.

[0032] Figure 7 Schematic diagram of signals and lip opening and closing of an electronic artificial larynx that implements start and stop control based on facial electromyographic signals according to an embodiment of the present invention.

[0033] Figure 8 The present invention is a flow chart of a signal recognition method for an electronic artificial larynx that implements start and stop control based on facial electromyographic signals according to an embodiment of the present invention.

[0034] Fig. 9 The figure is a schematic diagram of signals and start and stop control of an electronic artificial larynx that implements start and stop control based on facial electromyographic signals according to an embodiment of the present invention.

[0035] Reference numerals:

[0036] 1—Power module 2—EMG signal acquisition module 3—EMG signal processing module

[0037] 4—Microelectric-to-force conversion system 5—Surface electrode 6—Myoelectric amplifier circuit 7—Myoelectric signal filtering and sampling circuit

[0038] 8—microprocessor 9—start and stop control circuit 10—electronic artificial larynx

[0039] 11—Facial electromyography signal when lips are open 12—Facial electromyography signal when lips are closed

[0040] 13—Enhanced electromyographic signal 14—Rectified electromyographic signal

[0041] 15—Smoothed electromyographic signal 16—Logic switch signal DETAILED DESCRIPTION

[0042] The present invention is further described below in conjunction with specific embodiments, but the embodiments are only exemplary and do not constitute any limitation to the scope of the present invention. It should be understood by those skilled in the art that the details and forms of the technical solution of the present invention can be modified or replaced without departing from the spirit and scope of the present invention, but these modifications and replacements all fall within the protection scope of the present invention.

[0043] like Figure 1 As shown, the present invention provides a system for controlling the start and stop of vibration of an electronic artificial larynx based on facial electromyographic signals, the system comprising a power supply module (1), a facial electromyographic signal acquisition module (2), an electromyographic signal processing module (3), and a micro electric-to-force conversion module (4).

[0044] in:

[0045] The power module (1) provides power for the entire system;

[0046] The myoelectric signal acquisition module (2) comprises a surface electrode (5), an myoelectric amplification circuit (6), and an myoelectric signal filtering and sampling circuit (7), and is used for detecting facial myoelectric signals in the lip opening and closing state. Figure 2 As shown;

[0047] A schematic diagram of the use of an electronic artificial larynx for realizing start and stop control based on facial electromyographic signals according to an embodiment of the present invention is shown in FIG. Figure 5 As shown, the surface electrode (5) is used to fit the facial skin and obtain myoelectricity using the half-cell principle;

[0048] The myoelectric amplifier circuit (6) is used to amplify the myoelectric signal, and adopts two-stage amplification;

[0049] The electromyographic signal filtering and sampling circuit (7) is used to filter and digitize the surface electromyographic signal acquired by the surface electrode (5) and amplified by (6), and provide the digitized signal to the signal processing module (3).

[0050] like Figure 3 The figure shows a configuration diagram of an electromyographic signal acquisition module of an electronic artificial larynx for realizing start-stop control based on facial electromyographic signals according to an embodiment of the present invention, wherein the electromyographic signal processing module (3) shown includes a microprocessor (8) and a start-stop control circuit (9), which is used to convert the electromyographic signal into a switch value as a start-stop control signal;

[0051] in:

[0052] The microprocessor (8) is used to convert the electromyographic signal provided by the electromyographic signal filtering and sampling module (7) into a start-stop control signal;

[0053] The start-stop control circuit (9) is used to drive the micro electric-to-power conversion module (4) to generate vibration or stop vibration.

[0054] The micro electric-to-force conversion module (4) is used to convert the circuit oscillation signal into mechanical vibration to produce electronic artificial laryngeal speech.

[0055] According to an embodiment of the present invention, a method for eliminating noise of an electronic artificial larynx based on facial electromyographic signals to realize start and stop control is as follows: Figure 6 As shown in the flowchart, it includes the following steps:

[0056] - Connect the device correctly, fit the surface electrodes to the facial skin, and turn on the electronic artificial laryngeal

[0057] Source switch;

[0058] - The user starts to make lip opening and closing movements according to the speaking needs;

[0059] - The electromyographic signal acquisition module 2 acquires the facial electromyographic signal related to the opening and closing action of the lips, amplifies the signal, and then sends the amplified signal to the signal processing module 3;

[0060] - The signal processing module 3 calculates the received facial electromyographic signal, wherein, when the lips are naturally closed, the facial muscles are in a relaxed state, and the electromyographic signal 12 ( Figure 7 ) has no significant fluctuation; when the user starts to speak, the facial muscles contract, driving the lips to open and close, at this time the signal processing module 3 receives a pulse electromyographic signal 11 corresponding to the frequency of facial muscle contraction; the microprocessor 8 identifies and classifies the electromyographic signal, and determines the opening and closing state of the lips based on the identified and classified electromyographic signal;

[0061] According to a specific embodiment of the present invention, the process of identifying and classifying the electromyographic signal and determining the opening and closing state of the lips includes:

[0062] First, the collected facial electromyographic signals are enhanced by 13 ( Fig. 9), which is used to amplify the amplitude of the weak signal; secondly, the electromyographic signal is filtered 14 to remove the negative part of the signal; the electromyographic signal is smoothed 15 again to extract the strength of the amplitude in the signal; finally, the electromyographic signal is binarized 16, so as to convert the continuous electromyographic signal into a logic switch signal, and the logic switch signal is used to control the start and stop of the electric-force conversion module 4. In this way, the microprocessor 8 sets the control switch value according to the lip sounding state, controls the electric-force conversion module 4 to stop working when the lips do not make a sound, and when the lips make a sound, the electric-force conversion module 4 is driven to vibrate to generate electronic artificial laryngeal voice after the inter-sound noise is eliminated, that is, the electric-force conversion module 4 only generates electronic artificial laryngeal voice when the user's lips make a sound, and stops working when the user's lips do not make a sound and / or between one sound and the next sound, thereby avoiding the generation of noise.

Claims

1. An electronic artificial larynx using control based on facial electromyographic signals, Features include: The power module (1) is used to supply power to all parts of the entire electronic artificial larynx. The surface electrode (5) is used to fit the user's facial skin to obtain myoelectric signals. The electromyographic amplifier circuit (6) is used to amplify the electromyographic signal. The electromyographic signal filtering and sampling part (7) filters and digitizes the electromyographic signal amplified by the electromyographic amplifier circuit (6), and provides the digitized electromyographic signal to the signal processing module (3). The start-stop control part (9) is used to convert the digitized electromyographic signal provided by the electromyographic signal filtering and sampling part (7) into a start-stop control signal. The micro electric-to-power conversion module (4) is used to generate mechanical vibration under the control of the start-stop control signal, thereby emitting the speech of the electronic artificial larynx. in: The electromyographic signal filtering and sampling part (7) performs filtering processing (14) on the electromyographic signal to remove the negative value part of the electromyographic signal, then performs smoothing processing (15) on the electromyographic signal to extract the amplitude of the signal, and then performs binarization processing on the electromyographic signal (16). The start-stop control part (9) uses the electromyographic signal after the binarization process (16) as a logic switch signal, and uses the logic switch signal to control the start and stop of the electric-to-power conversion module (4).

2. The electronic artificial larynx according to claim 1, Features: The surface electrode (5) uses the half-cell principle to obtain electromyographic signals; The myoelectric amplifier circuit (6) adopts two-stage amplification.

3. The electronic artificial larynx according to claim 1, Features: The start-stop control part (9) is used to convert the digitized myoelectric signal into a switch quantity as a start-stop control signal.

4. The electronic artificial larynx according to any one of claims 1 to 3, Features: The electronic artificial larynx sets a control switch value according to the vocalization state of the user's lips. When the lips do not make a sound, the electric-force conversion module is controlled to stop working. When the lips make a sound, the electric-force conversion module is driven to vibrate to produce electronic artificial larynx voice with the inter-sound noise eliminated. That is, the electric-force conversion module only produces electronic artificial larynx voice when the user's lips make a sound. The electric-force conversion module stops working when the user's lips do not make a sound and between one sound and the next, thereby avoiding the generation of noise.

5. An electronic artificial larynx noise reduction method based on the electronic artificial larynx according to claim 1, Features include: The surface electrodes (5) are used to collect the user's facial electromyographic signals. The electromyographic signal is amplified by an electromyographic amplifier circuit (6). The amplified electromyographic signal is filtered and digitized by the electromyographic signal filtering and sampling part (7). The start-stop control part (9) converts the digitized electromyographic signal provided by the electromyographic signal filtering and sampling part (7) into a start-stop control signal. A micro electric-to-power conversion module (4) is used to generate mechanical vibration under the drive of a start-stop control signal, thereby producing speech of an electronic artificial larynx.

6. The electronic artificial larynx noise reduction method according to claim 5, Features: The surface electrode (5) uses the half-cell principle to obtain electromyographic signals; The myoelectric amplifier circuit (6) adopts two-stage amplification.

7. The electronic artificial larynx noise reduction method according to claim 5, Features: The start-stop control part (9) converts the myoelectric signal digitized by the microprocessor (8) into a switch quantity as a start-stop control signal of the micro-electric-power conversion module (4).

8. The electronic artificial larynx noise reduction method according to claim 5, Features Further including: The electronic artificial larynx is controlled to set a switch value according to the lip sounding state of the user. When the lips do not make a sound, the electric-force conversion module (4) is controlled to stop working. When the lips make a sound, the electric-force conversion module (4) is driven to vibrate and generate electronic artificial larynx speech with inter-sound noise eliminated. That is, the electric-force conversion module (4) generates electronic artificial larynx speech only when the lips of the user make a sound. When the lips of the user do not make a sound and / or between one sound and the next, the electric-force conversion module (4) stops working, thereby avoiding the generation of noise.

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