CN105181070A - Method and device for measuring liquid volume in container on basis of sound resonance - Google Patents
Method and device for measuring liquid volume in container on basis of sound resonance Download PDFInfo
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- CN105181070A CN105181070A CN201510602861.1A CN201510602861A CN105181070A CN 105181070 A CN105181070 A CN 105181070A CN 201510602861 A CN201510602861 A CN 201510602861A CN 105181070 A CN105181070 A CN 105181070A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F22/00—Methods or apparatus for measuring volume of fluids or fluent solid material, not otherwise provided for
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- General Physics & Mathematics (AREA)
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
- Measurement Of Levels Of Liquids Or Fluent Solid Materials (AREA)
Abstract
The invention discloses a method and device for measuring the liquid volume in a container on the basis of sound resonance. The method includes the following steps that a cavity is formed in the container, sound signals containing at least two types of frequency components are emitted into the cavity, sound signals resonated through the cavity are received, and the volume of liquid in the container is obtained on the basis of the sound-energy ratio of all frequency components in the resonated sound signals. The space size can be directly measured, the shape of the container is not limited, and therefore the method and device can be suitable for the container with the irregular cavity, the requirements for the calmness of the liquid surface and the placing posture of the container are low, and the application range is wide; the structure is simple, the size is small, sealing of the container and measuring of the liquid volume are combined, and use is quite convenient.
Description
Technical field
The present invention relates to the detection field of liquid volume, especially relate to a kind of measuring method and device of liquid volume.
Background technology
Ultrasonic liquid level measuring technology is widely used in the measurement of liquid volume, its ultimate principle is for send ultrasound wave to liquid level, then the voice signal after reflection is received, just total distance that ultrasound wave is advanced can be drawn according to mistiming and the velocity of sound, and then just can obtain the height of liquid level, the volume of liquid is tried to achieve afterwards by this height and vessel cross-sectional area, but there is some restrictions in the process that uses in reality of this mode: 1, because be indirectly obtain liquid volume by liquid level, therefore require that the cross sectional shape of container will be consistent, otherwise will difficulty in computation be increased, even cause calculating, 2, hyperacoustic directivity is extremely strong, therefore it all has higher requirements to the peace of the water surface and the installation direction of ultrasonic probe and stability, when the water surface is uncalm or ultrasonic probe generation deformation and displacement time, be difficult to measure the water yield exactly.
Based on above-mentioned deficiency, the present invention proposes a kind of universality is strong, precision is high measuring method and device.
Summary of the invention
In order to overcome the deficiencies in the prior art, the invention provides a kind of liquid in container volume measuring method based on resonance of the voice, can the volume of direct measurement space, the shape of container is not limited, thus the container with irregular cavity is gone for, simultaneously to the tranquil degree of liquid level and the placement Gesture of container lower, applied widely; Structure is simple, and compact, is combined as a whole the sealing of container and liquid capacity metering, uses very convenient.
The invention provides a kind of liquid volume measuring device based on resonance of the voice.
The technical solution adopted for the present invention to solve the technical problems is:
Based on a liquid in container volume measuring method for resonance of the voice, comprise the following steps,
S10 forms a cavity in container;
S20 launches the voice signal comprising at least two kinds of frequency contents in cavity;
S30 receives the voice signal after cavity resonance;
S40 is based on the volume of the acoustic energy accounting acquisition liquid in container of each frequency content in voice signal after sympathetic response.
As the further improved procedure of such scheme, voice signal is white noise.
As the further improved procedure of such scheme, the centre frequency of white noise is 3000Hz.
As the further improved procedure of such scheme, cavity is a cavity closed.
As the further improved procedure of such scheme, it is 100ms that the transmitting of voice signal continues duration.
As the further improved procedure of such scheme, the method obtaining liquid in container volume in step S40 is:
S41 tests voice signal acoustic energy accounting of each frequency content after sympathetic response in the space of different volumes in advance, forms database;
S42 obtains the volume of container;
S43 obtains the volume of cavity according to the acoustic energy accounting of each frequency content of voice signal in step S30 and database;
Difference between S44 vessel volume and cavity volume is the volume of testing liquid.
As the further improved procedure of such scheme, being transmitted in after cavity is formed of voice signal starts to carry out after certain interval of time.
As the further improved procedure of such scheme, voice signal be received in the transmitting of voice signal after carry out immediately.
As the further improved procedure of such scheme, comprise the step of the voice signal received being carried out to noise reduction process.
A kind of liquid volume measuring device, for detecting the volume of the liquid be stored in a container, comprises
As the main body of bearing structure;
Loudspeaker, it is located in this main body, for launching voice signal in container;
Microphone, it is located in this main body, for receiving the voice signal after container sympathetic response;
Control system, in container, launch voice signal for control loudspeaker, control the voice signal after microphones sympathetic response and the acoustic energy accounting of each frequency content in voice signal after detecting sympathetic response, and obtain the volume of liquid based on vessel volume and acoustic energy accounting.
As the further improved procedure of such scheme, the voice signal that loudspeaker is launched is white noise, and stores database in control system, and database is this voice signal database of each frequency content acoustic energy accounting after sympathetic response in the space of different volumes.
As the further improved procedure of such scheme, main body is a container or a lid.
As the further improved procedure of such scheme, comprise the conducting strip at least two places be located in main body, it is in the same plane, and loudspeaker and microphone were started working after a period of time between conducting strip after conducting.
As the further improved procedure of such scheme, comprise the conductive stator be located in main body, and correspondence is located at the shell fragment below stator, can elastic movement be there is in shell fragment, thus have and the first state of stator conducting and the second state of disconnecting with stator, loudspeaker and starting working after microphone a period of time after shell fragment is in the first state.
The invention has the beneficial effects as follows:
Can the volume of direct measurement space, the shape of container is not limited, goes for the container with irregular cavity, simultaneously to the tranquil degree of liquid level and the placement Gesture of container lower, applied widely; Structure is simple, and compact, is combined as a whole the sealing of container and liquid capacity metering, uses very convenient.
Accompanying drawing explanation
Below in conjunction with drawings and Examples, the present invention is further described.
Fig. 1 is the process flow diagram of detection method;
Fig. 2 is the oscillogram of voice signal after sympathetic response when liquid measure is less in container;
Fig. 3 is the spectrogram of voice signal after sympathetic response when liquid measure is less in container;
Fig. 4 is the oscillogram of voice signal after sympathetic response when liquid measure is more in container;
Fig. 5 is the spectrogram of voice signal after sympathetic response when liquid measure is more in container;
Fig. 6 is that pick-up unit of the present invention is as structural representation during lid.
Embodiment
Clear, complete description is carried out, to understand object of the present invention, scheme and effect fully below with reference to embodiment and the accompanying drawing technique effect to design of the present invention, concrete structure and generation.It should be noted that, when not conflicting, the embodiment in the application and the feature in embodiment can combine mutually.
It should be noted that, if no special instructions, when a certain feature is called as " fixing ", " connection " in another feature, it can directly be fixed, be connected in another feature, also indirectly can fix, be connected in another feature.In addition, it is only relative to the mutual alignment relation of each ingredient of the present invention in accompanying drawing that the upper and lower, left and right used in the present invention etc. describe.
In addition, unless otherwise defined, all technology used herein are identical with the implication that those skilled in the art understand usually with scientific terminology.The term used in instructions is herein to describe specific embodiment, instead of in order to limit the present invention.Term as used herein " and/or " comprise the arbitrary combination of one or more relevant Listed Items.
Principle of the present invention is based on the sympathetic response of sound, the voice signal including at least two kinds of frequency contents is emitted in the cavity of a limited bulk, continue for some time rear stopping and launching sound, now voice signal will leave lingering sound in cavity, form sympathetic response with this cavity.If the small volume of cavity, the resonating effect of high-frequency sound is comparatively strong, then the HFS in lingering sound is relatively strong; On the contrary, if the volume of cavity is comparatively large, the resonating effect of low-frequency sound is comparatively strong, then the low frequency part in lingering sound is relatively strong.
According to above physical phenomenon, this programme discloses a kind of liquid in container volume measuring method.The water yield in container is more, and the volume of cavity is less, then the resonating effect of high-frequency sound is strengthened; Otherwise the water yield in container is fewer, the volume of cavity is larger, then the resonating effect of low-frequency sound is strengthened.Concrete, with reference to Fig. 1, it comprises the following steps:
S10 forms a cavity in container, this cavity can make voice signal vibe wherein, it is preferably a closed cavity, preferred, itself or the cavity of a sound insulation, certainly, the present invention does not require that cavity seals completely, it can offer the structure such as hole, seam according to user demand, only need ensure this hole, the impact of crack structure on measurement result be in controllable degree.
S20 launches the voice signal comprising at least two kinds of frequency contents in cavity.
S30 receives the voice signal after cavity resonance, forms oscillogram, then changes oscillogram into spectrogram through fast fourier transform, obtained the acoustic energy accounting of each frequency content by spectrogram;
S40 obtains the volume of liquid in container based on above-mentioned acoustic energy accounting.
As a preferred embodiment of voice signal, it is white noise, preferred, and the centre frequency of described white noise is 3000Hz.
Further, it is a fixed value that the transmitting of voice signal continues duration, and the value of duration is preferably 100ms, to make voice signal have enough energy, is convenient to follow-up reception.
Corresponding above-mentioned voice signal, a kind of method for optimizing obtaining liquid in container volume in step S40 is:
S41 sets up the correspondence database of voice signal each frequency content acoustic energy accounting after the space sympathetic response of different volumes, and it is by having tested in advance in the present embodiment.Concrete, the first bulking value of fixed cavity, then launches voice signal and voice signal after receiving sympathetic response, obtains the acoustic energy accounting of each frequency content in voice signal in this cavity.Then change the bulking value of cavity, again measure when other test conditions are identical, arranged by all data acquisitions and form database, the numerical value of bulking value single variation is unsuitable excessive, to obtain more accurate database.
S42 obtains the volume of testing container.
S43, according to the acoustic energy accounting of each frequency content detecting acquisition in step S30, goes out the volume of cavity in conjunction with database backstepping.
The bulking value that vessel volume value is deducted cavity by S44 just can obtain the bulking value of testing liquid.
Because the aerial velocity of propagation of sound is very fast, in order to prevent voice signal excessive attenuation, in step S30 voice signal be received in the transmitting of voice signal in step S20 after carry out immediately.
In addition, noise may be there is because of residual the causing of the collision between component or outside noise in cavity in cavity when just being formed, therefore the launching and receiving of voice signal starts to carry out after certain interval of time after cavity is formed, to eliminate the interference of noise, preferably, this time interval is 1s.
In order to better precision can be improved, also comprise the step of the voice signal received being carried out to noise reduction process.
With reference to Fig. 2 to Fig. 5, show the oscillogram of same sound signal in the cavity of different volumes after sympathetic response and spectrogram, the transverse axis of oscillogram is the time, and the longitudinal axis is amplitude; The transverse axis of spectrogram is frequency, and the longitudinal axis is the acoustic energy size that this frequency content is carried.Wherein centered by voice signal, frequency is the white noise of 3000Hz, and transmitting duration is 100ms, and from information in figure, when the water yield is less, the cavity volume in container is comparatively large, make the low frequency part in lingering sound more, and HFS is less; When the water yield is more, cavity volume in container is little, make the HFS in lingering sound more, and low frequency part is less, by the proportion shared by lingering sound medium-high frequency and low-frequency component acoustic energy, then can judge the cavity size in container, and then can deduct by container capacity the water yield that cavity size obtains in container.
The invention also discloses a kind of measurement mechanism, with reference to Fig. 6, it comprises main body 1, loudspeaker 2, microphone 3 and control system (not shown).Wherein, main body 1 as bearing structure, for installing described loudspeaker, microphone and control system.Loudspeaker 2 and microphone 3 are under control of the control system, carry out the launching and receiving of voice signal respectively, voice signal after sympathetic response detects through control system and obtains the acoustic energy accounting of each frequency content, and systems axiol-ogy obtains the volume of liquid based on the volume of container and acoustic energy accounting.
Preferably, the voice signal that described loudspeaker is launched is white noise, and it has fixing transmitting and continues duration.Store database in control system, this database is this voice signal database of each frequency content acoustic energy accounting after sympathetic response in the space of different volumes.
As a preferred embodiment of measurement mechanism, it can be an independent structure, for the measurement of existing liquid in container volume, as the monitoring of oil mass in automotive oil tank, be independently measurement mechanism by main body 1, loudspeaker 2, microphone 3 and control system integration, then this measurement mechanism be installed on the measurement that just can complete liquid measure in fuel tank.
As another preferred embodiment of measurement mechanism, measurement mechanism itself also can form a part for cavity.In the present embodiment, main body is preferably a container or a lid, and when main body is container, loudspeaker 2, microphone 3 are arranged on container with control system, and it needs to coordinate container cover to form above-mentioned cavity; Similar, when main body is lid, loudspeaker 2, microphone 3 are arranged on lid with control system, and it needs to coordinate container to form above-mentioned cavity.The present embodiment preferably adopts main body to be the situation of lid, and be applicable to container such as kettle 4 grade, the sealing of kettle 4 and liquid inspection can be integrated by it, user-friendly.
Be understandable that, loudspeaker 2, microphone 3 also can be arranged in container and container cover respectively with control system.
In order to make liquid capacity metering more accurate, measurement mechanism also comprises flip flop equipment.As an embodiment of flip flop equipment, take main body as the situation of container cover be example, comprise the conducting strip at least two places be located in container cover, it is in same level, is applicable to the container with conductive capability.When forming cavity between lid and container, vessel port contacts with conducting strip simultaneously, thus forms galvanic circle between conducting strip, and then triggering loudspeaker 2 is started working with microphone 3.
Above-described embodiment is only applicable to the container with conducting function, then its function cannot be realized for the container be made up of insulating material, in addition due to the existence of error, may occur that container cannot touch the situation of stop means simultaneously, causing cannot synchro measure, therefore, the invention discloses further improved procedure, flip flop equipment comprises conductive stator, and correspondence is located at the shell fragment below stator, can there is elastic movement in shell fragment, thus have and the first state of described stator conducting and the second state of disconnecting with described stator.When lid becomes after cavity with shape of container, vessel port supports shell fragment makes it contact with stator, thus forms galvanic circle between shell fragment and stator, and then triggers loudspeaker and microphone works.
For eliminating the impact of residual noise, loudspeaker and microphone were started working after a period of time on triggering.
Be more than two kinds of typical triggering modes disclosed by the invention, but the present invention is not limited to these two kinds, it also can be Hall magnetic induction type, photo-electric, field coupled formula etc.
More than that better enforcement of the present invention is illustrated, but the invention is not limited to described embodiment, those of ordinary skill in the art also can make all equivalent variations or replacement under the prerequisite without prejudice to spirit of the present invention, and these equivalent distortion or replacement are all included in the application's claim limited range.
Claims (14)
1., based on a liquid in container volume measuring method for resonance of the voice, comprise the following steps,
S10 forms a cavity in container;
S20 launches the voice signal comprising at least two kinds of frequency contents in cavity;
S30 receives the voice signal after cavity resonance;
S40 is based on the volume of the acoustic energy accounting acquisition liquid in container of each frequency content in voice signal after sympathetic response.
2. the liquid in container volume measuring method based on resonance of the voice according to claim 1, is characterized in that, described voice signal is white noise.
3. the liquid in container volume measuring method based on resonance of the voice according to claim 2, is characterized in that, the centre frequency of described white noise is 3000Hz.
4. the liquid in container volume measuring method based on resonance of the voice according to claim 3, is characterized in that, described cavity is a cavity closed.
5. the liquid in container volume measuring method based on resonance of the voice according to claim 3, is characterized in that, it is 100ms that the transmitting of voice signal continues duration.
6. the liquid in container volume measuring method based on resonance of the voice according to any one of claim 1 to 5, is characterized in that, the method obtaining liquid in container volume in step S40 is:
S41 tests voice signal acoustic energy accounting of each frequency content after sympathetic response in the space of different volumes in advance, forms database;
S42 obtains the volume of container;
S43 obtains the volume of cavity according to the acoustic energy accounting of each frequency content of voice signal in step S30 and database;
Difference between S44 vessel volume and cavity volume is the volume of testing liquid.
7. the liquid in container volume measuring method based on resonance of the voice according to claim 6, is characterized in that, being transmitted in after cavity is formed of voice signal starts to carry out after certain interval of time.
8. the liquid in container volume measuring method based on resonance of the voice according to claim 7, is characterized in that, voice signal be received in the transmitting of voice signal after carry out immediately.
9. the liquid in container volume measuring method based on resonance of the voice according to any one of claim 1 to 5, is characterized in that, comprises the step of the voice signal received being carried out to noise reduction process.
10. a liquid volume measuring device, for detecting the volume of the liquid be stored in a container, is characterized in that, comprising
As the main body of bearing structure;
Loudspeaker, it is located in this main body, for launching voice signal in container;
Microphone, it is located in this main body, for receiving the voice signal after container sympathetic response;
Control system, in container, launching voice signal for controlling described loudspeaker, controlling the voice signal after described microphones sympathetic response and detecting the acoustic energy accounting of each frequency content in voice signal after sympathetic response, and obtain the volume of liquid based on vessel volume and acoustic energy accounting.
11. liquid volume measuring devices according to claim 10, it is characterized in that, the voice signal that described loudspeaker is launched is white noise, and storing database in described control system, described database is this voice signal database of each frequency content acoustic energy accounting after sympathetic response in the space of different volumes.
12. liquid volume measuring devices according to claim 10 or 11, it is characterized in that, described main body is a container or a lid.
13. liquid volume measuring devices according to claim 12, it is characterized in that, comprise the conducting strip at least two places be located in described main body, it is in the same plane, and described loudspeaker and microphone were started working after a period of time between conducting strip after conducting.
14. liquid volume measuring devices according to claim 12, it is characterized in that, comprise the conductive stator be located in described main body, and correspondence is located at the shell fragment below described stator, can elastic movement be there is in described shell fragment, thus have and the first state of described stator conducting and the second state of disconnecting with described stator, described loudspeaker and starting working after microphone a period of time after shell fragment is in the first state.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510602861.1A CN105181070A (en) | 2015-09-21 | 2015-09-21 | Method and device for measuring liquid volume in container on basis of sound resonance |
| PCT/CN2015/090957 WO2017049657A1 (en) | 2015-09-21 | 2015-09-28 | Acoustic resonance-based method and device for measuring liquid volume in container |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510602861.1A CN105181070A (en) | 2015-09-21 | 2015-09-21 | Method and device for measuring liquid volume in container on basis of sound resonance |
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| CN105181070A true CN105181070A (en) | 2015-12-23 |
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| CN201510602861.1A Pending CN105181070A (en) | 2015-09-21 | 2015-09-21 | Method and device for measuring liquid volume in container on basis of sound resonance |
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| WO (1) | WO2017049657A1 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107421604A (en) * | 2017-04-26 | 2017-12-01 | 珠海智牧互联科技有限公司 | A kind of audio material-level detection system and method |
| CN109060077A (en) * | 2018-08-16 | 2018-12-21 | 杭州容大智造科技有限公司 | A kind of equipment and Wiper system using bath of glass height in sound detection water tank |
| CN109937445A (en) * | 2016-11-01 | 2019-06-25 | 株式会社小泉制作所 | Drinking container for cheers etc. and as the drinking container of small bell |
| CN113358176A (en) * | 2021-06-01 | 2021-09-07 | 南方科技大学 | Method and device for measuring volume of container content, measuring equipment and medium |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115727926A (en) * | 2022-11-18 | 2023-03-03 | 陕西师范大学 | Liquid level detection method based on equivalent specific area of probe energy on inner wall of liquid tank |
| CN116380714B (en) * | 2023-03-15 | 2023-09-22 | 中国科学院地理科学与资源研究所 | Water sample sand content measuring device and measuring method using same |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7216536B2 (en) * | 2001-06-22 | 2007-05-15 | Young Manufacturing & Engineering, Inc. | Acoustic volume indicator |
| US8061198B2 (en) * | 2008-09-11 | 2011-11-22 | Yinko IP Holdings, LLC | Measuring cup sensor and system |
| CN101571724B (en) * | 2009-06-17 | 2011-01-12 | 南京大学 | Measurement and control method for intelligent acoustic control of liquid level |
| CN102252729A (en) * | 2011-06-08 | 2011-11-23 | 张仲生 | Device and method for measuring volume of irregular object |
| CN202255529U (en) * | 2011-10-10 | 2012-05-30 | 北京华阳利民仪器有限公司 | Liquid volume measuring device |
| CN203981236U (en) * | 2014-07-09 | 2014-12-03 | 邓博团 | A kind of dispensing device of automatic measurement liquid volume |
| CN104568044B (en) * | 2014-11-25 | 2018-10-02 | 中北大学 | A kind of flexible package liquid volume measurement device and method |
| CN204630631U (en) * | 2015-04-24 | 2015-09-09 | 深圳麦开网络技术有限公司 | A kind of measurement mechanism of liquid in container volume and container |
-
2015
- 2015-09-21 CN CN201510602861.1A patent/CN105181070A/en active Pending
- 2015-09-28 WO PCT/CN2015/090957 patent/WO2017049657A1/en active Application Filing
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109937445A (en) * | 2016-11-01 | 2019-06-25 | 株式会社小泉制作所 | Drinking container for cheers etc. and as the drinking container of small bell |
| CN107421604A (en) * | 2017-04-26 | 2017-12-01 | 珠海智牧互联科技有限公司 | A kind of audio material-level detection system and method |
| CN109060077A (en) * | 2018-08-16 | 2018-12-21 | 杭州容大智造科技有限公司 | A kind of equipment and Wiper system using bath of glass height in sound detection water tank |
| CN113358176A (en) * | 2021-06-01 | 2021-09-07 | 南方科技大学 | Method and device for measuring volume of container content, measuring equipment and medium |
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| WO2017049657A1 (en) | 2017-03-30 |
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Application publication date: 20151223 |