CN102783973B - Vocal-cord vibration nondestructive measurement method utilizing natural sound track ultraphonic waveguide effect - Google Patents
Vocal-cord vibration nondestructive measurement method utilizing natural sound track ultraphonic waveguide effect Download PDFInfo
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- CN102783973B CN102783973B CN201210278461.6A CN201210278461A CN102783973B CN 102783973 B CN102783973 B CN 102783973B CN 201210278461 A CN201210278461 A CN 201210278461A CN 102783973 B CN102783973 B CN 102783973B
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Abstract
The invention discloses a vocal-cord vibration nondestructive measurement method by utilizing a natural vocal track ultraphonic waveguide effect. The method comprises the following steps of: stimulating an ultrasonic wave through an air ultrasonic transducer, and guiding the ultrasonic wave into an oral cavity and a vocal track; transmitting the ultrasonic wave in a natural acoustic waveguide formed by a vocal track of a human body to arrive a vibrated vocal track; through reflection of a surface of the vocal track, transmitting the ultrasonic wave back to the oral cavity through the vocal track, and detecting a reflection echo through the air ultrasonic transducer; after digitalizing a reflection signal, computing frequency deviation of the reflection signal relative to a transmitting signal; obtaining relative movement speed of a refection surface of the ultrasonic wave (i.e. the surface of the vocal track) through a doppler frequency shift formula; and integrating a speed value so as to obtain a movement displacement signal of the reflection surface of the ultrasonic wave. According to the vocal-cord vibration nondestructive measurement method provided by the invention, the ultrasonic transducer has no need to be stretched into the deep part of the vocal track, an examined patient has no need to maintain a particular body posture to straighten the vocal track, and higher safety and usability are realized.
Description
Technical field
The present invention relates to a kind of non-intrusion type detection method of vocal cord vibration, is a kind of ultrasound waveguide effect of human body sound channel and method that hyperacoustic doppler shift effect detects the vertical vibration of vocal cords upper surface utilized specifically.
Background technology
Vocal cord vibration is the sound source of human speech, and it is playing the part of a crucial role in the production process of voice.Meanwhile, vocal cords are also one of human body vitals, and vocal cord vibration extremely also closely related with a lot of throat diseases, as vocal nodule, vocal cords edema etc.Therefore, the detection of vocal cord vibration information, both had important value to being familiar with the sound generating mechanism of normal and irregular voice; Also to preventing, diagnose, assess some throat diseases to there is important clinical value.Just because of these reasons, the clinic diagnosis of phoniatrics, laryngopathy etc. has urgent demand to the new technique of detection by quantitative vocal cord vibration information.
Common method for detection of vocal cord vibration mainly contains several inspection methods such as ElectroglottographicWaveform, light glottogram, laryngoscope and high-speed photography endoscope at present.ElectroglottographicWaveform be while utilizing sounding about in vocal cords closing course the variation of contact resistance carry out the Vibration Condition of indirect detection vocal cords, it is only effective to the close stage in vocal cord vibration cycle.Light glottogram is to utilize the variation of the logical light quantity of glottis opening stage in voiced process to carry out the motion conditions of indirect detection vocal cords, and it is only responsive to the opening stage in vocal cord vibration cycle.ElectroglottographicWaveform is all to detect the physical quantity relevant to vocal cord vibration to carry out inverting vocal cord vibration information with light glottogram, although they are all the measuring methods of harmless non-intrusion type, but they can only obtain vocal cords lateral vibration information, and these information are Relative Vibration signals, rather than the quantitative information of vocal cord vibration (as actual displacement, speed etc.).Laryngoscope and high-speed photography endoscope are that the vocal cord vibration of another two kinds of current clinical frequent uses is observed and measuring method.These two kinds of methods are based on optical imagery means, but due to the straightline propagation characteristic of light and the natural torsion shape of sound channel, while adopting laryngoscope or high-speed photography endoscope to detect vocal cord vibration, optical fiber must be stretched into sound channel or patient and must keep given pose, therefore, these methods are not complete non-invasive measuring method, and its range of application is limited to.Generally speaking, conventional vocal cord vibration detection method all has its shortcoming and application limitation at present.
Summary of the invention
The object of this invention is to provide a kind of natural phonation waveguide effect of human body sound channel and new method of non-invasively nondestructive measurement vocal cords surface vertical vibration of ultrasonic Doppler effect utilized, the method is made detection by quantitative to the speed of vocal cords surface vibration in voiced process and displacement, for clinic diagnosis of phoniatrics, laryngopathy etc. provides reliable basis.
The technical solution used in the present invention is: a kind of vocal cord vibration non-destructive measuring method that utilizes nature sound channel ultrasound waveguide effect, comprises the following steps:
(1) use a Y type conduit to be used for coupling track and two air ultrasound transducers, an air ultrasound transducer is used air ultrasound transducer for transmitting, is arranged on the first port of Y type conduit; Another air ultrasound transducer is used air ultrasound transducer for receiving, and is arranged on the second port of Y type conduit; Transmitting is connected with signal generator with air ultrasound transducer, receives with air ultrasound transducer and is connected with signal amplifier, and signal amplifier is connected with oscillograph, and oscillograph is connected with computer;
(2) the 3rd port (not connecing the port of air ultrasound transducer) that measured people aims at Y type conduit with normal posture and sounding custom carries out sounding;
(3) described signal generator generation frequency is
f t sinusoidal signal, by transmitting, use air ultrasound transducer to be converted to ultrasound wave, and incide the first port of Y type conduit; Y type conduit guiding ultrasound wave enters in detected person's mouth, and sound channel will further play the effect of nature ultrasound waveguide, and ultrasonic signal is guided to vocal cords; Ultrasound wave, after vocal cords surface reflection, then via the sound channel conduction chamber of answering back, is coupled into Y type conduit, and receivedly with air ultrasound transducer, receives, and signal is exaggerated rear digitized sampling and is stored in computer;
If the vocal cords surface as ultrasonic reflections cross section is a plane of movement, due to ultrasonic Doppler effect, reflective sound wave is with respect to incident acoustic wave, and its frequency will be offset,
(1)
In formula (1),
f t represent incident ultrasonic frequency,
f r represent reflectance ultrasound wave frequency.Difference on the frequency between incident acoustic wave and reflective sound wave
f d =
f r –
f t be called Doppler frequency.The size of Doppler frequency meets following formula:
(2)
In formula (2)
vthe projected size of vocal cords surface movement velocity in incident transonic direction,
c air it is the airborne velocity of sound.If the ultrasonic reflection face direction of motion is consistent with incident ultrasonic propagation direction,
vget on the occasion of, otherwise,
vget negative value.If ||
v|| much smaller than the airborne velocity of sound
c air , formula (2) can be reduced to
(3)
In the present invention, ultrasound wave is by the sound channel vocal cords that lead, ultrasound wave be near normal incide the upper surface of vocal cords, therefore, we can think speed approx
vin fact be the vertical direction component of vocal cords upper surface vibration with representing.When vocal cords move upward (
v< 0), Doppler frequency be on the occasion of
f d > 0; Otherwise, when vocal cords move downward (
v> 0), Doppler frequency is negative value
f d < 0.Therefore formula (3) shows that Doppler frequency is carrying the movable information of ultrasonic reflections face.
(4) utilize the ultrasonic reflection signal that Hilbert transform pairs receives to carry out demodulation, obtain Doppler frequency signal
f d ;
(5) due to the velocity peak values of the vocal cord vibration magnitude lower than ~ 1 meter per second, and temperature is while being 36 Co, and the airborne velocity of sound is about 352 meter per seconds, so meet ||
v|| <<
c air , accordingly, the speed that moves both vertically that the Doppler frequency information that we can obtain according to demodulation and formula (3) are tried to achieve vocal cords surface,
(4)
(6) then the rate signal that moves both vertically on vocal cords surface is carried out to integration to the time, can further obtain the displacement that moves both vertically on vocal cords surface,
(5)
The present invention is by air ultrasound transducer excitation ultrasound ripple and by ultrasound waveguide entrance cavity, sound channel, the vocal cords that vibrating are propagated and arrived to ultrasound wave in the natural phonation waveguide consisting of human body sound channel, reflection through vocal cords surface, ultrasound wave is passed oral cavity back via sound channel and again by air ultrasound transducer detection of reflected echo, reflected signal is carried out after digitized, calculate again the frequency shift (FS) that reflected signal transmits relatively, and by Doppler shift formula, obtain the movement velocity of ultrasonic reflections surface (being vocal cords surfaces), again velocity amplitude is carried out to the moving displacement signal that integration just can obtain ultrasonic reflections surface.
In the present invention, the sound channel of human body has been played the part of the effect of a natural phonation waveguide.Sound channel to vocal cords, guides the ultrasonic leading of transmitting transducer transmitting to receiving transducer by the reflection supersonic wave via vocal cords reflection again simultaneously.Therefore, the vocal cord vibration measuring method that the present invention proposes, need not extend into ultrasonic transducer sound channel depths, does not also need checked patient to keep specific body gesture to stretch sound channel.In addition, the low frequency ultrasound adopting in the present invention is as detected carrier, to human-body safety, and not damaged.Therefore, the vocal cord vibration monitoring method that the present invention proposes is the non-invasive detection method can't harm completely, has higher safety and ease for use.
beneficial effect:the present invention compares with at present conventional vocal cord vibration measuring method, has the following advantages:
(1) the present invention has utilized human body sound channel as natural ultrasound waveguide, guide the propagation of ultrasound wave between ultrasonic transducer and the measured vocal cords, avoided transducer to be stretched into sound channel or requiring patient to keep special body position to stretch sound channel, therefore, this invention is completely non-invasive, and it is easier to daily larynx functional check.
(2) the present invention utilizes ultrasonic Doppler effect to measure vocal cord vibration, the Doppler frequency and the Doppler's formula that according to demodulation, obtain, and the present invention can obtain speed and the displacement absolute value of vocal cord vibration, and is not only the relative size of speed and displacement.
(3) the present invention can obtain movement velocity and the displacement of the vocal cords upper surface vertical direction that other method can not record at present.
(4) measurement device of the present invention is simple, is easy to realize.
Accompanying drawing explanation
The system schematic of Fig. 1 vocal cord vibration measuring method of the present invention.
Fig. 2 is the measurement result of the inventive method to the vibration of respiratory body band
Fig. 3 is the measurement result of the inventive method to whispered pectoriloquy voiced process vocal cord vibration.
Fig. 4 is the measurement result of the inventive method to voice/a/ voiced process vocal cord vibration.
The specific embodiment
Below in conjunction with the drawings and specific embodiments, the present invention will be further described.
A vocal cord vibration non-destructive measuring method that utilizes nature sound channel ultrasound waveguide effect, comprises the following steps:
(1) as shown in Figure 1, use a Y type conduit 1 to be used for coupling track and two air ultrasound transducers, an air ultrasound transducer is air ultrasound transducer 2 for transmitting, is arranged on the first port of Y type conduit 1; Another air ultrasound transducer, for receiving with air ultrasound transducer 3, is arranged on the second port of Y type conduit 1; Transmitting is connected with signal generator 4 with air ultrasound transducer 2, receives with air ultrasound transducer 3 and is connected with signal amplifier 5, and signal amplifier 5 is connected with oscillograph 6, and oscillograph 6 is connected with computer 7;
(2) the 3rd port that measured people aims at Y type conduit with normal posture and sounding custom carries out sounding;
(3) described signal generator generation frequency is
f t sinusoidal signal, by transmitting, use air ultrasound transducer to be converted to ultrasound wave, and incide the first port of Y type conduit; Y type conduit guiding ultrasound wave enters in detected person's mouth, and sound channel will further play the effect of nature ultrasound waveguide, and ultrasonic signal is guided to vocal cords; Ultrasound wave, after vocal cords surface reflection, then via the sound channel conduction chamber of answering back, is coupled into Y type conduit, and receivedly with air ultrasound transducer, receives, and signal is exaggerated rear digitized sampling and is stored in computer;
(4) utilize the ultrasonic reflection signal that Hilbert transform pairs receives to carry out demodulation, obtain Doppler frequency signal
f d ;
(5) the Doppler frequency information obtaining according to demodulation is tried to achieve the speed that moves both vertically on vocal cords surface
;
(6) then the rate signal that moves both vertically on vocal cords surface is carried out to integration to the time, can further obtain the displacement that moves both vertically on vocal cords surface
.
Embodiment 1:
As shown in Figure 2, detected person is required to breathe facing to the port of Y type conduit, but does not want sounding.Signal generator produces the sinusoidal signal that frequency is 350kHz, and uses air ultrasound transducer to produce the ultrasound wave that frequency is 350kHz by transmitting.Via the guiding of Y type conduit, by ultrasound waveguide to oral cavity.Ultrasonic echo is received with air ultrasound transducer by another reception, and the sample frequency with 100MHz after amplifying is sampled, and is stored in computer.Adopt Hilbert transform pairs ultrasound echo signal to carry out, after demodulation, can obtaining Doppler frequency.The in the situation that of this not sounding, because body band does not vibrate, so ultrasonic reflections face is a stationary face.The Doppler frequency value that adopts method of the present invention to obtain is also very little, according to formula
with
, can in the hope of speed and the displacement of vocal cord vibration, all approach 0, the state that has recorded vocal cord vibration that method of the present invention is correct.
Embodiment 2:
As shown in Figure 3, detected person is required to send out whispered pectoriloquy/a/ facing to the port of Y type conduit, and the waveform of this voice signal is as shown in Fig. 2 (d).Signal generator produces the sinusoidal signal that frequency is 350kHz, and uses air ultrasound transducer to produce the ultrasound wave that frequency is 350kHz by transmitting.Via the guiding of Y type conduit, by ultrasound waveguide to oral cavity.Ultrasonic echo is received with air ultrasound transducer by another reception, and the sample frequency with 100MHz after amplifying is sampled, and is stored in computer.Adopt Hilbert transform pairs ultrasound echo signal to carry out, after demodulation, can obtaining Doppler frequency.The generation of whispered pectoriloquy just push high velocity air by glottis and is produced the high velocity turbulent flow noise that can hear, and through a kind of aperiodic irregular voice of sound channel modulation generation, at the voiced process of whispered pectoriloquy, does not also produce vocal cord vibration.The Doppler frequency value that adopts method of the present invention to obtain is very little, according to formula
with
, can all approach 0 in the hope of speed and the displacement of vocal cord vibration, the state that has recorded the vocal cord vibration under whispered pectoriloquy sounding condition that method of the present invention is correct.
Embodiment 3:
As shown in Figure 4, detected person is required the port facing to Y type conduit, with normal tune, sends out vowel/a/, and signal generator produces the sinusoidal signal that frequency is 350kHz, and uses air ultrasound transducer to produce the ultrasound wave that frequency is 350kHz by transmitting.Via the guiding of Y type conduit, by ultrasound waveguide to oral cavity.Ultrasonic echo is received with air ultrasound transducer by another reception, and the sample frequency with 100MHz after amplifying is sampled, and is stored in computer.Adopt Hilbert transform pairs ultrasound echo signal to carry out, after demodulation, can obtaining Doppler frequency.
The generation of vowel is the result of body band vibrational excitation glottis, and in the voiced process of vowel, body band produces periodic vibration.Adopt method of the present invention to record, under normal vowel sounding condition, there is obvious frequency shift (FS) in the ultrasonic signal being reflected back through body band upper surface.Positive Doppler frequency represents that vocal cords upper surface moves upward, and negative Doppler frequency represents that vocal cords upper surface moves downward.According to the Doppler frequency value of measuring and demodulation obtains, and air themperature 36 Co in hypothesis sound channel, the speed that sound wave is propagated is therein
c air=352 meter per seconds, utilize formula
the speed that moves both vertically of vocal cords upper surface in the time of can be in the hope of vowel sounding.According to measurement result of the present invention, the peak-to-peak value of body band vibration velocity is about 0.16 meter per second.This result is consistent with the result that finite element modelling, half larynx experiment measuring obtain.Utilize method of the present invention, the correct state that has recorded the vocal cord vibration under vowel sounding condition.
It should be pointed out that for those skilled in the art, under the premise without departing from the principles of the invention, can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.In the present embodiment not clear and definite each ingredient all available prior art realized.
Claims (1)
1. a vocal cord vibration non-destructive measuring method that utilizes nature sound channel ultrasound waveguide effect, is characterized in that: comprise the following steps:
(1) use a Y type conduit to be used for coupling track and two air ultrasound transducers, an air ultrasound transducer is used air ultrasound transducer for transmitting, is arranged on the first port of Y type conduit; Another air ultrasound transducer is used air ultrasound transducer for receiving, and is arranged on the second port of Y type conduit; Transmitting is connected with signal generator with air ultrasound transducer, receives with air ultrasound transducer and is connected with signal amplifier, and signal amplifier is connected with oscillograph, and oscillograph is connected with computer;
(2) the 3rd port that measured people aims at Y type conduit with normal posture and sounding custom carries out sounding;
(3) described signal generator generation frequency is f
tsinusoidal signal, by transmitting, use air ultrasound transducer to be converted to ultrasound wave, and incide the first port of Y type conduit; Y type conduit guiding ultrasound wave enters in detected person's mouth, and sound channel will further play the effect of nature ultrasound waveguide, and ultrasonic signal is guided to vocal cords; Ultrasound wave, after vocal cords surface reflection, then via the sound channel conduction chamber of answering back, is coupled into Y type conduit, and receivedly with air ultrasound transducer, receives, and signal is exaggerated rear digitized sampling and is stored in computer;
(4) utilize the ultrasonic reflection signal that Hilbert transform pairs receives to carry out demodulation, obtain Doppler frequency signal f
d;
(5) the Doppler frequency information obtaining according to demodulation is tried to achieve the speed that moves both vertically on vocal cords surface
c
airit is the airborne velocity of sound;
(6) then the rate signal that moves both vertically on vocal cords surface is carried out to integration to the time, can further obtain the displacement that moves both vertically on vocal cords surface
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| CN103169505B (en) * | 2013-03-19 | 2016-01-13 | 北京银河之舟环保科技有限公司 | A kind of doppler ultrasound pickup APU |
| CN103323094B (en) * | 2013-06-24 | 2014-12-03 | 中国航空工业集团公司北京长城计量测试技术研究所 | Heterodyne laser interference angle vibration measuring method |
| CN103690195B (en) * | 2013-12-11 | 2015-08-05 | 西安交通大学 | The ultrasonic laryngostroboscope system that a kind of ElectroglottographicWaveform is synchronous and control method thereof |
| US20180289354A1 (en) * | 2015-09-30 | 2018-10-11 | Koninklijke Philips N.V. | Ultrasound apparatus and method for determining a medical condition of a subject |
| CN110826515A (en) * | 2019-11-13 | 2020-02-21 | 三峡大学 | Closed idiosyncrasy singing tone detection device |
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| WO2002077972A1 (en) * | 2001-03-27 | 2002-10-03 | Rast Associates, Llc | Head-worn, trimodal device to increase transcription accuracy in a voice recognition system and to process unvocalized speech |
| CN101502425A (en) * | 2009-03-09 | 2009-08-12 | 西安交通大学 | System and method for detecting characteristic of vocal cord vibration mechanics |
| US7676372B1 (en) * | 1999-02-16 | 2010-03-09 | Yugen Kaisha Gm&M | Prosthetic hearing device that transforms a detected speech into a speech of a speech form assistive in understanding the semantic meaning in the detected speech |
| CN201912125U (en) * | 2010-12-30 | 2011-08-03 | 广州宝胆医疗器械科技有限公司 | Integrated color Doppler ultrasound electronic laryngoscope system |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US20080262391A1 (en) * | 2007-04-23 | 2008-10-23 | Mark Peter Ottensmeyer | Instrument for measuring the mechanical properties of vocal tissues |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7676372B1 (en) * | 1999-02-16 | 2010-03-09 | Yugen Kaisha Gm&M | Prosthetic hearing device that transforms a detected speech into a speech of a speech form assistive in understanding the semantic meaning in the detected speech |
| WO2002077972A1 (en) * | 2001-03-27 | 2002-10-03 | Rast Associates, Llc | Head-worn, trimodal device to increase transcription accuracy in a voice recognition system and to process unvocalized speech |
| CN101502425A (en) * | 2009-03-09 | 2009-08-12 | 西安交通大学 | System and method for detecting characteristic of vocal cord vibration mechanics |
| CN201912125U (en) * | 2010-12-30 | 2011-08-03 | 广州宝胆医疗器械科技有限公司 | Integrated color Doppler ultrasound electronic laryngoscope system |
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