CN117629390B - Ultra-low frequency strong infrasound calibration device - Google Patents
Ultra-low frequency strong infrasound calibration device Download PDFInfo
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- CN117629390B CN117629390B CN202311566895.0A CN202311566895A CN117629390B CN 117629390 B CN117629390 B CN 117629390B CN 202311566895 A CN202311566895 A CN 202311566895A CN 117629390 B CN117629390 B CN 117629390B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H17/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves, not provided for in the preceding groups
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Abstract
The invention discloses an ultralow frequency strong infrasound calibration device, which comprises an ultralow frequency vibration table system, a strong infrasound generator, a pressure sensor and a measurement and control system; the ultralow frequency vibration table system comprises a vibration table and a signal generator, wherein the signal generator generates ultralow frequency sinusoidal signals with the frequency of 0.001 Hz-20 Hz, and drives the vibration table to generate sinusoidal vibration; the strong infrasound generator comprises a cavity and a piston, the piston is connected with the vibration table, the piston generates reciprocating sinusoidal motion under the driving of sinusoidal vibration of the vibration table, and air in the cavity is compressed to generate infrasound signals; the pressure sensor collects pressure signals in a cavity of the intensive subsonic generator, and the subsonic sensor collects subsonic signals in the cavity; the measurement and control system collects the output of the pressure sensor and the calibrated ultrasonic sensor, and realizes the calibration of the calibrated ultrasonic sensor by calculation and comparison. The invention can solve the problem of tracing the ultra-low frequency strong secondary acoustic sensor by comparing and calibrating the secondary acoustic sensor.
Description
Technical Field
The invention belongs to the field of infrasound sensor calibration, and particularly relates to an ultralow frequency strong infrasound calibration device.
Background
Infrasonic waves widely exist in nature and human activities, such as earthquake, volcanic eruption, debris flow, nuclear explosion, supersonic flight, weapon targeting and the like, and have the characteristics of strong penetrating capacity, long propagation distance, reduced attenuation and the like, and are widely applied to the fields of environmental monitoring, military fields, industrial production and the like. In recent years, with the wide application of the infrasound sensor in the fields of national defense and military industry such as nuclear explosion monitoring, weapon targeting positioning and the like, the demand for monitoring ultra-low frequency and strong infrasound signals is put forward, the 3dB lower limit frequency of the existing infrasound sensor can reach 0.001Hz, and the measuring range can reach 10kPa (namely 174 dB). The monitoring of the infrasound sound pressure signal mainly depends on an infrasound sensor, the accurate measurement of the infrasound sound pressure mainly depends on the calibration of the infrasound sensor, and the magnitude of the infrasound sensor is accurately the premise and the guarantee of the application of the sensor.
The calibration method of the secondary acoustic sensor mainly comprises a coupling cavity reciprocity method and a gas cavity pressure method. The coupling cavity reciprocity method is only suitable for calibrating infrasound sound pressure above 2Hz, and is the most widely applied air cavity pressure method for calibrating an infrasound sensor under low frequency, namely, the volume of gas in a cavity is changed through an electromagnetic driver or other driving mechanisms, so that dynamic pressure is obtained, and the calibration of a sensor is realized.
At present, the calibration of the domestic and foreign infrasound sensor mainly uses a laser piston generator, the magnitude transmission of the laser piston generator method mainly obtains the sound pressure of infrasound signals through calculation of a theoretical model after measuring particle vibration velocity by laser, and the main disadvantages of the method include: (1) With the reduction of the frequency, the air leakage is more serious, and the calculation model is more difficult to correct, so that the frequency is not suitable for being too low, and the applicable calibration frequency range is (0.1-20) Hz; (2) With the increase of sound pressure level, in the high sound pressure range, the small-amplitude sound wave assumption of the piston generator method is no longer established, the corresponding wave equation becomes a nonlinear wave equation, and nonlinear factors caused by large amplitude can introduce higher harmonics, so that the correction of the calculation model is more difficult.
Therefore, an ultralow frequency strong infrasound calibration device is required to be designed so as to solve the tracing problem of an infrasound sensor under ultralow frequency and strong infrasound.
Disclosure of Invention
The invention aims to provide an ultralow frequency strong infrasound calibration device which can generate infrasound sound pressure signals with the frequency of 0.001 Hz-20 Hz and the amplitude of 124 dB-174 dB, and the problem of tracing the ultralow frequency strong infrasound sensor can be solved by comparing and calibrating the infrasound sensor.
The invention provides an ultralow frequency strong infrasound calibration device, which comprises an ultralow frequency vibration table system, a strong infrasound generator, a pressure sensor and a measurement and control system;
The ultralow frequency vibrating table system comprises a vibrating table and a signal generator, wherein the signal generator generates an ultralow frequency sinusoidal signal with the frequency of 0.001 Hz-20 Hz, and drives the vibrating table to generate sinusoidal vibration;
the strong infrasound generator comprises a cavity and a piston, the piston is connected with the vibration table, the piston generates reciprocating sinusoidal motion under the driving of sinusoidal vibration of the vibration table, and air in the cavity is compressed to generate infrasound signals;
The pressure sensor and the calibrated infrasound sensor are arranged on the intense infrasound generator, the pressure sensor is used for collecting pressure signals in a cavity of the intense infrasound generator, and the calibrated infrasound sensor is used for collecting infrasound signals in the cavity;
The measurement and control system is used for collecting the output of the pressure sensor and the calibrated secondary acoustic sensor, and the calibrated secondary acoustic sensor is calibrated by calculation and comparison.
Preferably, the ultralow frequency vibration table system further comprises a power amplifier and a motion controller, wherein the power amplifier is used for amplifying the ultralow frequency sinusoidal signal generated by the signal generator, and the motion controller is used for performing feedback control on the displacement of the vibration table.
Preferably, the intensive sound generator further comprises a piston dynamic sealing device, a sensor mounting end cover, a sensor mounting tool and a sensor pre-tightening mechanism;
The piston dynamic seal device is arranged at the piston end of the cavity and used for realizing dynamic seal of the piston, the sensor installation end cover is arranged at the sensor end of the cavity and used for realizing seal of the sensor end of the cavity, the sensor installation end cover is provided with a sensor installation tool, the sensor installation tool is used for clamping the pressure sensor and the calibrated ultrasonic sensor, and the pressure sensor and the calibrated ultrasonic sensor are arranged on the sensor installation tool through a sensor pre-tightening mechanism.
Preferably, the measurement and control system calculates the pressure signal acquired by the pressure sensor through fast fourier transform to obtain the sound pressure value of the infrasound signal, and the calibrated infrasound sensor is calibrated by comparing the sound pressure value with the infrasound signal acquired by the calibrated infrasound sensor.
According to the ultra-low frequency strong infrasound calibration device disclosed by the invention, infrasound sound pressure signals with the frequencies of 0.001 Hz-20 Hz and the amplitudes of 124 dB-174 dB can be generated, and the tracing problem of the ultra-low frequency strong infrasound sensor can be solved by calibrating the infrasound sensor by a comparison method and tracing the pressure basic quantity.
Drawings
For a clearer description of the technical solutions of the present invention, the following description will be given with reference to the attached drawings used in the description of the embodiments of the present invention, it being obvious that the attached drawings in the following description are only some embodiments of the present invention, and that other attached drawings can be obtained by those skilled in the art without the need of inventive effort:
FIG. 1 is a schematic diagram of an ultra-low frequency strong infrasound calibration device in accordance with one embodiment of the present invention;
Wherein: the device comprises a 1-signal generator, a 2-motion controller, a 3-vibrating table, a 4-piston dynamic sealing device, a 5-cavity, a 6-sensor mounting tool, a 7-pressure sensor, an 8-measurement and control system, a 9-calibrated secondary acoustic sensor, a 10-sensor pre-tightening mechanism, a 11-sensor mounting end cover, a 12-piston and a 13-power amplifier.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
An embodiment of the present invention provides an ultralow frequency intense-infrasound calibration device, as shown in fig. 1, which includes an ultralow frequency vibration table system, an intense-infrasound generator, a pressure sensor 7 and a measurement and control system 8.
The ultra-low frequency vibrating table system comprises a vibrating table 3, a power amplifier 13, a motion controller 2 and a signal generator 1. The signal generator 1 generates ultralow frequency sinusoidal signals with the frequency of 0.001 Hz-20 Hz, the sinusoidal signals are amplified by the power amplifier 13 and then drive the vibrating table 3 to generate sinusoidal vibration, and the motion controller 2 is used for feedback control of the displacement of the vibrating table 3 so as to realize accurate control of the displacement of the vibrating table 3.
The intensive subsonic generator comprises a cavity 5, a piston 12, a piston dynamic sealing device 4, a sensor mounting end cover 11, a sensor mounting tool 6 and a sensor pre-tightening mechanism 10. The piston 12 is connected with the vibration table 3, the piston 12 generates reciprocating sinusoidal motion under the driving of sinusoidal vibration of the vibration table 3, the piston 12 is coupled with the cavity 5, and the reciprocating sinusoidal motion of the piston 12 compresses air in the cavity 5 to generate infrasound signals. The piston dynamic sealing device 4 is arranged at the piston end of the cavity 5 and is used for realizing dynamic sealing of the piston 12; the sensor mounting end cover 11 is arranged at the sensor end of the cavity 5, so that the sealing of the sensor end can be realized, and two tool mounting holes are formed in the sensor mounting end cover 11 and are used for mounting the sensor mounting tool 6 for clamping the pressure sensor 7 and the calibrated secondary acoustic sensor 9. For calibrated secondary sensors 9 of different sizes, quick installation can be achieved by replacing the sensor installation tooling 6. The pressure sensor 7 and the calibrated secondary acoustic sensor 9 are arranged on the sensor installation tool 6 through a sealing structure and a sensor pre-tightening mechanism 10, so that the acoustic tightness is ensured, and no acoustic leakage is generated in the intensive secondary acoustic generator. Through the reasonable size of the cavity, the infrasound generation of 124 dB-174 dB can be realized.
The pressure sensor 7 is a reference sensor in the ultra low frequency intense infrasound calibration device of the present invention for measuring the static pressure within the intense infrasound generator. Since the infrasound signal is represented as fluctuation of pressure in the cavity, fluctuation of pressure in the cavity 5 is measured by the pressure sensor 7, and reproduction of the infrasound signal can be realized based on the pressure measurement result. For the infrasound signals of 0.001 Hz-20 Hz, the pressure change in the cavity 5 is slower, when the sampling rate of the pressure sensor 7 exceeds 2.56 times of the frequency of the infrasound signals, the complete capture of the infrasound signals can be realized, the pressure change value of the cavity 5, namely the infrasound sound pressure signal, is obtained, and then the calibration of the calibrated infrasound sensor 9 is realized through a comparison method.
The measurement and control system 8 comprises a pressure sensor collector and a secondary acoustic sensor collector, and can collect the output of the reference pressure sensor 7 and the corrected secondary acoustic sensor 9, calculate the output and calibrate the sensitivity, the frequency response and the linearity of the corrected secondary acoustic sensor 9 under strong secondary acoustic.
The working method of the ultralow frequency strong infrasound calibration device provided by the embodiment of the invention comprises the following steps:
The vibration table 3 generates standard sinusoidal vibration under the control of the signal generator 1, the motion controller 2 and the power amplifier 13, and drives the piston 12 to generate reciprocating sinusoidal motion; the piston 12 is coupled with the cavity 5, one end of the cavity 5 is sealed by the piston dynamic sealing device 4, and the other end is sealed by the sensor mounting end cover 11. The reciprocating movement of the piston 12 within the sealed space of the chamber 5 compresses the air within the chamber 5 to produce a standard infrasound signal.
The reference pressure sensor 7 and the calibrated infrasound sensor 9 are arranged on a sensor installation end cover 11 through a sensor installation tool 6, and the same standard infrasound signals are collected; the cavity pressure signal acquired by the reference pressure sensor 7 is calculated by FFT (fast Fourier transform) to obtain the sound pressure value of the infrasound signal, the infrasound signal is acquired by the infrasound sensor 9 and then the voltage value is output, and the calibration of the infrasound sensor 9 is realized by calculation of a comparison method.
The ultralow frequency strong infrasound calibration device provided by the embodiment of the invention has the following beneficial effects:
1. the invention drives the strong infrasound generator through the ultra-low frequency vibrating table system, can realize the ultra-low frequency strong infrasound generation with the frequency of 0.001 Hz-20 Hz and the amplitude of 124 dB-174 dB, and is used for calibrating the sensitivity, the frequency response and the linearity of the infrasound sensor under the strong infrasound.
2. According to the invention, through the sensor mounting tool and the sensor pre-tightening mechanism, the sealing between various types of subsonic sensors and the intense subsonic generators is realized, and the rapid and convenient mounting can be realized.
3. The method takes the pressure sensor as a reference sensor, realizes dynamic measurement of the infrasound signal by measuring the pressure change in the intense infrasound generator, is a direct measurement method, effectively avoids model correction errors caused by factors such as pressure leakage and the like in the traditional laser piston generator method, and has higher measurement precision.
While certain exemplary embodiments of the present invention have been described above by way of illustration only, it will be apparent to those of ordinary skill in the art that modifications may be made to the described embodiments in various different ways without departing from the spirit and scope of the invention. Accordingly, the drawings and description are to be regarded as illustrative in nature and not as restrictive of the scope of the invention, which is defined by the appended claims.
Claims (2)
1. The ultra-low frequency strong infrasound calibration device is characterized by comprising an ultra-low frequency vibration table system, a strong infrasound generator, a pressure sensor and a measurement and control system;
The ultralow frequency vibrating table system comprises a vibrating table and a signal generator, wherein the signal generator generates an ultralow frequency sinusoidal signal with the frequency of 0.001 Hz-20 Hz, and drives the vibrating table to generate sinusoidal vibration;
the strong infrasound generator comprises a cavity and a piston, the piston is connected with the vibration table, the piston generates reciprocating sinusoidal motion under the driving of sinusoidal vibration of the vibration table, and air in the cavity is compressed to generate infrasound signals;
The pressure sensor and the calibrated infrasound sensor are arranged on the intense infrasound generator, the pressure sensor is used for collecting pressure signals in a cavity of the intense infrasound generator, and the calibrated infrasound sensor is used for collecting infrasound signals in the cavity;
The measurement and control system is used for collecting the output of the pressure sensor and the calibrated secondary acoustic sensor, and realizing the calibration of the calibrated secondary acoustic sensor by calculation and comparison,
The ultra-low frequency vibrating table system also comprises a power amplifier and a motion controller, wherein the power amplifier is used for amplifying the ultra-low frequency sinusoidal signal generated by the signal generator, the motion controller is used for carrying out feedback control on the displacement of the vibrating table,
The strong infrasound generator further comprises a piston dynamic sealing device, a sensor mounting end cover, a sensor mounting tool and a sensor pre-tightening mechanism;
The piston dynamic sealing device is arranged at the piston end of the cavity and used for realizing dynamic sealing of the piston, the sensor installation end cover is arranged at the sensor end of the cavity and used for realizing sealing of the sensor end of the cavity, the sensor installation end cover is provided with a sensor installation tool which is used for clamping the pressure sensor and the calibrated acoustic sensor, the pressure sensor and the calibrated acoustic sensor are arranged on the sensor installation tool through a sensor pre-tightening mechanism,
The pressure sensor is a reference sensor in the ultra-low frequency strong infrasound calibration device and is used for measuring fluctuation of pressure in a cavity of the strong infrasound generator, realizing reproduction of infrasound signals according to pressure measurement results, obtaining pressure change values in the cavity as infrasound signals, and further realizing calibration of the calibrated infrasound sensor through a comparison method.
2. The ultra-low frequency strong infrasound calibration device of claim 1, wherein the measurement and control system calculates the pressure signal collected by the pressure sensor through fast fourier transform to obtain the sound pressure value of the infrasound signal, and the calibrated infrasound sensor is realized by comparing the sound pressure value with the infrasound signal collected by the calibrated infrasound sensor.
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102538944A (en) * | 2012-01-11 | 2012-07-04 | 浙江大学 | Infrasound generating device based on displacement feedback type vibration table |
| CN109916504A (en) * | 2019-04-10 | 2019-06-21 | 中国航空工业集团公司北京长城计量测试技术研究所 | A kind of amplitude and the adjustable high sound pressure microphone calibration apparatus with traceability of frequency |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| FR2523339A1 (en) * | 1982-03-12 | 1983-09-16 | Guglielmetti Vg Electro | INFRA-SOUND VOLUMETRIC SENSOR DETECTION DEVICE AND INFRA-SOUND DETECTION METHOD |
| FR2820820B1 (en) * | 2001-02-15 | 2004-04-16 | Commissariat Energie Atomique | DEVICE FOR CALIBRATING A PRESSURE SENSOR, IN PARTICULAR AN INFRASON PRESSURE SENSOR |
| DE102009058797B4 (en) * | 2009-12-18 | 2019-01-10 | Ssl Gmbh - Sicherheitssysteme Landenberg | A method of performing infrasound intrusion detection |
| CN201828334U (en) * | 2010-09-26 | 2011-05-11 | 中国计量科学研究院 | Ultra-low-frequency vibration metering instrument calibration system and laser interferometer thereof |
| KR101364516B1 (en) * | 2013-12-05 | 2014-02-19 | 한국지질자원연구원 | Calibration method of infrasound detection system |
| GB2583440B (en) * | 2019-01-18 | 2023-02-15 | Gaiacode Ltd | Infrasound detector |
| CN111289095B (en) * | 2020-02-24 | 2023-11-03 | 南京俏声波动科技有限公司 | Sinusoidal pressure wave standard source for sensor calibration and working method thereof |
| CN114018397B (en) * | 2021-10-28 | 2024-09-20 | 中国舰船研究设计中心 | Hydrophone arc array low-frequency calibration device and calibration method thereof |
| CN114526808B (en) * | 2022-02-15 | 2024-07-05 | 中国航空工业集团公司北京长城计量测试技术研究所 | Infrasound air sound calibrating device |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102538944A (en) * | 2012-01-11 | 2012-07-04 | 浙江大学 | Infrasound generating device based on displacement feedback type vibration table |
| CN109916504A (en) * | 2019-04-10 | 2019-06-21 | 中国航空工业集团公司北京长城计量测试技术研究所 | A kind of amplitude and the adjustable high sound pressure microphone calibration apparatus with traceability of frequency |
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