JP2007051952A - Acoustic sensor device, acoustic analysis diagnosis device, and method of manufacturing acoustic sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an acoustic sensor device and an acoustic analysis diagnosis device for analyzing and diagnosing a sound from a measuring object in real time with a comparatively simple constitution, and to provide a method of manufacturing an acoustic sensor. <P>SOLUTION: A data collection/transmission circuit 30 detects only a sound in each different frequency band in the whole band by resonance of each of a plurality of acoustic sensors 11-15 with each different sound, converts it into data by data conversion circuits 21-25, and transmits the data from a data transmission circuit 32 through an antenna 33 by a control part 31. A data transmission/analysis diagnosis circuit 40 receives data corresponding to the plurality of acoustic sensors 11-15, compares a sound pressure stored beforehand with a sound pressure by the received data, and can determine whether the measuring object is normal or abnormal. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an acoustic sensor device, an acoustic analysis diagnostic device, and an acoustic sensor manufacturing method. For example, the present invention relates to an acoustic sensor device, an acoustic analysis diagnostic device, and an acoustic sensor manufacturing method using a resonator that vibrates in response to sound vibration. .

  Conventionally, various equipment diagnosis methods have been proposed in order to determine the presence or absence of an abnormality in equipment or equipment. In such an equipment diagnosis method, it is possible to continue to operate sufficiently before the serious accident, for example, the bearing in the rotating machine is damaged or the wear of moving parts has progressed. If left as it is, an abnormality that may lead to a serious failure in the future is detected.

  For example, “Diagnostic engineering by sound / diagnosis” edited by Japan Acoustical Society, Corona (Non-patent Document 1) collects sound using a directional microphone in order to diagnose and analyze engine noise. It is described that the signal sound is diagnosed.

In Japanese Patent Application Laid-Open No. 2004-20584 (Patent Document 1), a signal indicating a physical quantity reflecting the state of a diagnosis target is obtained by a sensor, and the signal is divided into band signals for a plurality of frequency bands. An abnormality monitoring apparatus and an abnormality monitoring program are described that determine the presence or absence of an abnormality to be diagnosed for each frequency band based on each determination criterion set for each of a plurality of band signals.
"Diagnosis engineering by sound and diagnosis", Japan Acoustical Society, Corona Japanese Patent Laid-Open No. 2004-20584

  In the diagnostic method using a microphone described in Non-Patent Document 1, when there is noise other than the target sound in the measurement environment, if the sound pressure of the noise is high, the output of the microphone is saturated due to the noise. The target sound cannot be captured. This is because the microphone is designed to have the same sensitivity in all detectable bands.

  In the apparatus described in Patent Document 1, a programmable bandpass filter is used to divide the output signal of the sensor into band signals for a plurality of frequency bands. In the program band pass filter, when the number of divisions of the band is n, the first frequency band is extracted first, and after the abnormality determination process for the extracted first band signal is completed, the second frequency band It is necessary to perform extraction and abnormality determination processing n times, such as performing extraction processing for. This process is a software process based on a program, and there is a problem that it takes a long time to perform a complicated operation.

  Therefore, an object of the present invention is to provide an acoustic sensor device, an acoustic analysis diagnostic device, and an acoustic sensor manufacturing method for analyzing sound from a measurement object in real time with a relatively simple configuration.

  The present invention is an acoustic sensor device for detecting at least a predetermined band of a wide band of sound emitted from an object to be measured, including a plurality of first vibrators that resonate according to different sounds. A first acoustic detection element that detects a first band sound and extracts a first characteristic sound to be measured, and a plurality of second vibrators that resonate according to different sounds, A second acoustic detection element that detects a second band sound different from the first band and extracts a second characteristic sound to be measured;

  An element necessary for detecting a wide band sound with one element is difficult to manufacture. However, the first and second acoustic detection elements are divided into a first acoustic detection element and a second acoustic detection element. Since the sound of the second predetermined band is detected, the difficulty in manufacturing the element can be solved.

  Preferably, the first acoustic detection element detects a predetermined band of the wide band sound emitted from the measurement target, and the second acoustic detection element detects a wide band wide sound from the measurement target. Detect the sound of the remaining band. As a result, the sound of the entire band can be detected and the state of the measurement target can be analyzed.

  Preferably, the first acoustic detection element detects a predetermined band of the wide band sound emitted from the measurement target, and the second acoustic detection element detects a wide band wide sound from the measurement target. A sound in a part of the predetermined band and a sound in the remaining band are detected.

  Preferably, the first characteristic sound indicates that the measurement target is normal, and the second characteristic sound indicates that the measurement target is abnormal. As a result, it is possible to diagnose whether the measurement target is normal or abnormal.

  Another aspect of the present invention is an acoustic diagnosis analyzer that detects, analyzes, and diagnoses at least a predetermined band of a wide band of sound emitted from a measurement target, each of which resonates according to a different sound. Multiple acoustic detectors that detect only sounds in different frequency bands, and analyze acoustic signals in different frequency bands that are output from multiple acoustic detectors. And an analysis / diagnostic unit that diagnoses the sound distribution and analyzes the characteristics of the measurement target.

  In the present invention, when a measurement target is a factory having a plurality of apparatus facilities having a plurality of failure modes, each failure mode can be diagnosed.

  Preferably, the analysis / diagnostic unit analyzes the normality / abnormality of the measurement target as a feature.

  Preferably, the analysis / diagnosis unit determines whether or not the maintenance inspection of the measurement target is necessary according to the analysis of the abnormality detection. Depending on the analysis result, the necessity of maintenance can be accurately determined.

  Still another aspect of the present invention is a method of manufacturing an acoustic sensor used for acoustic analysis of a measurement target, the step of preparing a plurality of acoustic detection elements each including a resonator that resonates according to different sounds; A process of collecting a plurality of acoustic detection elements in the vicinity of the measurement target, collecting the measurement target data according to the purpose, and resonating with a predetermined band of the plurality of acoustic detection elements based on the collected data Determining a combination of acoustic detection elements to perform. By this combination, monitoring and diagnosis according to the state of the measurement target can be performed.

  According to this invention, the measurement target is provided with the first acoustic detection element that extracts the first characteristic sound of the measurement target and the second acoustic detection element that extracts the second characteristic sound of the measurement target. The sound from the measurement object can be analyzed in real time with a relatively simple configuration according to the characteristic sound.

  In addition, by resonating with different sounds, only sounds in different frequency bands are detected within a wide band, and each sound signal output from multiple sound detection elements is analyzed. By diagnosing the sound distribution and analyzing the characteristics of the measurement object, the sound from the measurement object can be analyzed in real time.

  In addition, prepare multiple acoustic detection elements that resonate with different sounds, install multiple acoustic detection elements near the measurement target, collect the measurement target data according to the purpose, and based on the collected data By determining a combination of acoustic detection elements that resonate with sound in a predetermined band among the plurality of acoustic detection elements, an acoustic detection element that analyzes sound from a measurement object in real time can be manufactured.

  FIG. 1 is a plan view of an example of an acoustic sensor device according to an embodiment of the present invention. In FIG. 1, an acoustic sensor device 1 as an acoustic sensing element is formed on a semiconductor silicon substrate 10 and includes a diaphragm 2, a transverse beam 3, an end plate 4, and a plurality of resonance beams 5.

  The diaphragm 2 is formed in a thin plate shape so as to vibrate upon receiving an input sound. The transverse beam 3 is formed so as to connect between the diaphragm 2 and the end plate 4, the width on the side of the diaphragm 2 is wide, and gradually becomes narrower from there toward the end plate 4, and at the end of the end plate 4. It is the thinnest.

  Each of the plurality of resonance beams 5 is adjusted in length so as to resonate at a specific frequency, and is cantilevered so as to extend from the transverse beam 3 to both sides. The acoustic sensor device 1 has a fishbone structure including a pair of resonance beams 5 and 5 having the same resonance frequency. The end plate 4 is provided so as to absorb vibration caused by the input sound propagating from the diaphragm 2 via the transverse beam 3 so as not to return to the diaphragm 2 side. The diaphragm 2, the transverse beam 3, the end plate 4, and the lower portions of the plurality of resonance beams 5 are spaces, and the periphery of the plurality of resonance beams 5 is opened.

  The diaphragm 2 vibrates vertically by the vibration caused by the input sound, the vibration propagates in the transverse beam 3 in the horizontal direction, and the corresponding vibrator of the plurality of resonance beams 5 vibrates vertically. By changing the length or thickness of the resonant beam 5, the respective resonant frequencies can be set to desired values. Each resonance beam 5 is provided with a piezoresistor (not shown) on the transverse beam 3 side, and a change in the resistance value of the piezoresistor can be extracted as, for example, an output of a Wheatstone bridge.

  2 is a diagram showing frequency response characteristics of a plurality of resonant beams in the acoustic sensor device shown in FIG. 1, FIG. 3 is a diagram showing input / output characteristics, and FIG. 4 is a diagram showing environmental noise tolerance.

  As shown in FIG. 2, the plurality of resonant beams 5 of the acoustic sensor device 1 shown in FIG. 1 are adjusted in length so as to resonate at a resonant frequency of 1.2 kHz to 2.5 kHz, for example. It is possible to selectively respond to the resonance frequency. Then, due to the interaction between the resonant beams 5, it is possible to respond to the frequency between the resonant frequencies.

  Further, when the diaphragm 2 is oscillated at the value shown on the horizontal axis shown in FIG. 3, the plurality of resonance beams 5 are oscillated at the value shown on the vertical axis in FIG. 3, so that the output can be amplified about 14 times.

  Furthermore, the acoustic sensor device 1 shown in FIG. 1 can detect a signal of a target sound even when an interference sound other than the target sound is input. A waveform a shown in FIG. 4 indicates an output waveform when a target sound (2900 Hz, 0.1 Pa) is input, a waveform b indicates an output waveform when a disturbing sound (500 Hz, 10 Pa) is input, and a waveform c indicates the target sound. The output waveform is shown when disturbing sound is input simultaneously. Even if an interference sound as noise is input from FIG. 4, it becomes possible to detect a target sound having a sound pressure 1/100 of the interference sound.

  FIG. 5 is a block diagram of an acoustic analysis diagnostic apparatus according to an embodiment of the present invention. FIG. 5A shows a data collection / transmission circuit, and FIG. 5B shows a data reception / analysis diagnosis circuit.

  In FIG. 5A, the data collection / transmission circuit 30 includes acoustic sensors 11 to 15, data conversion circuits 21 to 25, a control unit 31, a data transmission circuit 32, and an antenna 33. The acoustic sensors 11 to 15 detect the entire band of sound in a wide band from the measurement target, and the acoustic sensor device 1 shown in FIG. 1 is used.

  For example, the acoustic sensor 11 is 500 Hz to 1 kHz, the acoustic sensor 12 is 900 Hz to 1.8 kHz, the acoustic sensor 13 is 1.7 kHz to 3.4 kHz, the acoustic sensor 14 is 3.3 kHz to 6.8 kHz, and the acoustic sensor 15 is 6. Resonant beams included in the acoustic sensors 11 to 15 are configured so as to resonate with sound of 7 kHz to 10 kHz. Thereby, the sound of the band of 600 Hz-10 kHz is detectable with the acoustic sensors 11-15, for example.

  If one acoustic sensor device 1 tries to detect a wide band of sound, the transverse beam becomes long and it is difficult to manufacture the resonant beam 5. For example, each acoustic sensor 11 to 15 divides each band. By detecting them, the resonant beam 5 can be manufactured relatively easily, and an unnecessary band vibrator can be omitted.

  In addition, according to a measuring object, a band can be set arbitrarily and the number of acoustic sensors may be increased so that the sound of all the bands output from the measuring object, for example, 600 Hz to 100 kHz, can be detected, or You may enable it to detect only a certain frequency band among the sound of all the bands output from a measuring object. Furthermore, one acoustic sensor may detect a certain band of the entire band, and another acoustic sensor may detect the remaining band.

  Outputs of the acoustic sensors 11 to 15 are given to the data conversion circuits 21 to 25. The data conversion circuits 21 to 25 A / D convert sound signals in the frequency band output from the acoustic sensors 11 to 15 and output the signals to the control unit 31 as sound pressure intensity distribution data. The control unit 31 sequentially outputs the data given from the data conversion circuits 21 to 25 to the data transmission circuit 32 in a time division manner, and the data transmission circuit 32 transmits each data from the antenna 33 by radio or light.

  The data reception / analysis diagnosis circuit 40 shown in FIG. 5B includes an antenna 41, a data reception circuit 42, an analysis diagnosis circuit 43, and a display unit 44. The data reception circuit 42 receives each data of each acoustic sensor 11 to 15 transmitted from the data collection / transmission circuit 30 via the antenna 41 and gives it to the analysis / diagnosis circuit 43.

  The analysis / diagnosis circuit 43 stores a sound pressure intensity distribution as data in advance according to the purpose of diagnosis, and compares the sound pressure intensity distribution with the sound pressure intensity given as data to extract a feature for diagnosis purposes. I do. That is, if the purpose of diagnosis is detection of a normal state or detection of an abnormal state, the sound pressure distribution of the sound when the measurement target is operating normally or abnormally is stored as a characteristic sound. Keep it. When the measurement target is abnormal, the sound pressure distribution of the sound different from that in the normal state appears, so the sound pressure intensity corresponding to each sound is stored in advance as a characteristic sound. It should be noted that the abnormal state includes a state in which the measurement target has failed and a state in which a failure of the measurement target is predicted.

  When the data corresponding to each of the acoustic sensors 11 to 15 is given, the analysis / diagnosis circuit 43 compares the sound pressure intensity with the sound pressure intensity stored in advance, and the optimal one of the acoustic sensors 11 to 15 is compared. Select a combination. The display unit 44 displays the selected combination of acoustic sensors.

  FIG. 6 is a flowchart for explaining the operation of the acoustic analysis / diagnosis apparatus according to the embodiment of the present invention. (A) shows the operation of the data collection / transmission circuit 30, and (B) shows the data reception / analysis diagnosis. The operation of the circuit 40 is shown.

  Next, with reference to FIG. 6, the operation of diagnosing normality or abnormality of the measurement object with the acoustic analysis diagnostic apparatus of one embodiment of the present invention will be described. The acoustic sensors 11 to 15 are arranged in the vicinity of the measurement target (not shown). When the measurement target is operated, the acoustic sensors 11 to 15 have the diaphragm 2 shown in FIG. 1 according to the sound emitted from the measurement target. It vibrates and propagates to the plurality of resonant beams 5 via the transverse beam 3. Among the plurality of resonance beams 5, the vibrator corresponding to the sound to be measured vibrates vertically. This vibration changes the resistance value of the piezoresistive element and is taken out as a change in voltage.

  A signal corresponding to the vibration of the sound corresponding to each acoustic sensor 11 to 15 is output from each of the acoustic sensors 11 to 15, supplied to the data conversion circuits 21 to 25, and A / D converted to the control unit 31 as data indicating the sound pressure intensity. Given. The control unit 31 determines whether or not data indicating the sound pressure intensity from the acoustic sensors 11 to 15 is input in the step SP1 (abbreviated as SP in the drawing) shown in FIG. 6A. If so, each data is sequentially transmitted from the data transmission circuit 32 via the antenna 33 in step SP2.

  The data reception circuit 42 of the data reception / analysis diagnostic circuit 40 shown in FIG. 5B determines whether or not all the data of the acoustic sensors 11 to 15 has been received in step SP11 shown in FIG. 6B. . If received, the analysis / diagnostic circuit 43 extracts a characteristic signal for diagnosis from the sound pressure intensity of each sound based on the data of each acoustic sensor 11-15 in step SP12, and in step SP13, the characteristic An acoustic sensor based on a combination of at least one or more for detecting a signal is determined as a signal detection device of the diagnosis target facility. And in step SP14, the applicable one of the acoustic sensors 11-15 which are the devices is displayed.

  The combination of the plurality of acoustic sensors 11 to 15 determined as the signal detection device is selected according to the purpose of diagnosis. For example, the purpose of diagnosis is determined by whether the measurement target is in a normal state, whether it is a failure prediction detection as an abnormal state, or a failure detection. The sound distribution from the object to be measured differs depending on whether it is normal, failure prediction, or failure, so the combination of acoustic sensors is determined so that each sound distribution can be detected. The For example, a combination of the acoustic sensors 12, 13, 15 is selected to detect a normal state, a combination of the acoustic sensors 11, 12, 13 is selected for detection of failure prediction, or the acoustic sensor 13, The combination of 14 and 15 is selected.

  As described above, according to this embodiment, each of the plurality of acoustic sensors 11 to 15 resonates with a different sound, so that only the sound for each different frequency band in the entire band is detected, and the plurality of acoustic sensors 11 to 11 are detected. 15 by analyzing acoustic signals of different frequency bands output from 15 and diagnosing the sound distribution, and by selecting a combination of acoustic sensors according to each feature, while having a relatively simple configuration Analyzes and diagnoses sound from the measurement object in real time.

  In addition, as the acoustic sensors 11 to 15, fishbone structure sensors each having a pair of resonance beams 5 and 5 are used, so that it is not necessary to perform frequency decomposition by software processing or the like, and frequency decomposition is performed in real time. Can do. Furthermore, since the calculation time required for the decomposition into each frequency band can be reduced, the processing time can be shortened.

  FIG. 7 is a diagram showing an example of analyzing and diagnosing the measurement target sound in all bands using the acoustic analysis and diagnosis apparatus according to another embodiment of the present invention, and FIG. 8 is an acoustic analysis and diagnosis of the example shown in FIG. It is a figure which shows the example which has arrange | positioned only the optimal acoustic sensor with an apparatus. Each of FIG. 7 and FIG. 8A shows a data collection / transmission circuit, and FIG. 7B shows a data reception / analysis diagnosis circuit.

  As shown in FIG. 7A, the acoustic sensors 11 to 15 are arranged in the vicinity of the measurement target 50. The data collection / transmission circuit 30a is configured by removing the acoustic sensors 11 to 15 from the data collection / transmission circuit 30 shown in FIG. 5A, and the data reception / analysis diagnosis circuit 40 is configured as shown in FIG. Based on the flowchart shown in Fig. 5, the sound from the measurement object 50 is analyzed and diagnosed in all bands. For example, in order to detect a normal state, a combination of the acoustic sensors 12, 13, and 15 is selected. FIG. 8A shows the arrangement of the selected acoustic sensors 12, 13, and 15.

  The data reception / analysis diagnostic circuit 40 shown in FIG. 8B collects sound data from the measurement object 50, analyzes and diagnoses whether the measurement object is in a normal state or an abnormal state, and measures the measurement object. Status monitoring such as determination of necessity of 50 maintenance is performed. As described with reference to FIG. 5, the acoustic sensors 11, 12, and 13 are disposed when the failure is predicted, and the acoustic sensors 13, 14, and 15 are disposed when the failure is detected.

FIG. 9 shows an acoustic analysis diagnostic apparatus according to another embodiment of the present invention, (A) is a conceptual diagram showing an example in which an acoustic sensor is arranged in a factory, and (B) shows a data reception / analysis diagnostic circuit. Show.
The 9A, in the factory 60, although not shown, a plurality of apparatus facilities having a plurality of failure modes are installed. For this reason, a plurality of abnormal noises are generated in the factory. Therefore, in this embodiment, a plurality of acoustic sensors 11 to 15 are disposed in order to detect individual abnormal sounds in the factory 60.

  Although not shown in FIG. 9A, the outputs of the acoustic sensors 11 to 15 are given to the data collection / transmission circuit 30a shown in FIG. The data reception / analysis diagnosis circuit 40 shown in FIG. 9B is arranged outside the factory 60. In the data reception / analysis diagnostic circuit 40, since the acoustic sensors 11 to 15 detect individual sounds, the equipment is normal or abnormal based on the data of the acoustic sensors 11 to 15, and maintenance is required. Monitor the status such as judgment.

  FIG. 10 shows an acoustic analysis / diagnosis apparatus according to still another embodiment of the present invention. (A) is a diagram showing an example in which an acoustic sensor is arranged in a unique apparatus. (B) is a data reception / analysis diagnosis circuit. Indicates.

  As shown in FIG. 10A, unique devices 71 to 74 are arranged in a factory or the like, and each of the devices 71 to 74 generates noise. The acoustic sensors 11 to 14 are arranged in proximity to the devices 71 to 74. The data reception / analysis diagnostic circuit 40 detects normal sounds of the devices 71 to 74 based on data given to the acoustic sensors 11 to 14 from a data collection / transmission circuit (not shown). Diagnosis such as judgment of abnormality and feature extraction can be performed.

  As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to the thing of embodiment shown in figure. Various modifications and variations can be made to the illustrated embodiment within the same range or equivalent range as the present invention.

  The acoustic sensor device, acoustic analysis / diagnosis device, and acoustic sensor manufacturing method of the present invention are used to determine whether there is an abnormality in equipment or equipment in a factory.

It is a top view of an example of an acoustic sensor device in one embodiment of this invention. It is a figure which shows the frequency response characteristic of the some resonant beam in the acoustic sensor apparatus shown in FIG. It is a figure which shows the input-output characteristic in an acoustic sensor apparatus. It is a figure which shows the environmental noise tolerance in an acoustic sensor apparatus. 1 is a block diagram of an acoustic analysis diagnostic apparatus according to an embodiment of the present invention. It is a flowchart for demonstrating operation | movement of the acoustic analysis diagnostic apparatus in one Embodiment of this invention. It is a figure which shows the example which analyzes and diagnoses a measuring object sound in all the bands using the acoustic analysis diagnostic apparatus of this invention. It is a figure which shows the example which has arrange | positioned only the optimal acoustic sensor with the acoustic analysis diagnostic apparatus of the example shown in FIG. It is a conceptual diagram which shows the example which has arrange | positioned the acoustic sensor in a factory. It is a figure which shows the example which has arrange | positioned the acoustic sensor to the intrinsic | native apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Acoustic sensor apparatus, 2 Diaphragm, 3 Cross beam, 4 End plate, 5 Resonance beam, 11-15 Acoustic sensor, 21-25 Data conversion circuit, 30, 30a Data collection and transmission circuit, 31 Control part, 32 Data transmission circuit 33, 41 Antenna, 40 Data reception / analysis diagnosis circuit, 42 Data reception circuit, 43 Analysis diagnosis circuit, 44 Display unit, 50 measurement object, 60 factories, 71-74 device.

Claims (8)

An acoustic sensor device that detects at least a predetermined band of a wide band of sound from a measurement target,
A first acoustic detection element that includes a plurality of first vibrators that resonate in response to different sounds, detects a first band sound within the band, and extracts a first characteristic sound of the measurement target; ,
A plurality of second vibrators that resonate according to different sounds, detecting a second band sound different from the first band within the band, and extracting a second characteristic sound to be measured An acoustic sensor device, comprising: a second acoustic sensing element that performs:   The first acoustic detection element detects a predetermined band of the wide band sound from the measurement target, and the second acoustic detection element detects a wide band sound from the measurement target. The acoustic sensor device according to claim 1, wherein a sound in the remaining band is detected.   The first acoustic detection element detects a predetermined band of the wide band sound from the measurement target, and the second acoustic detection element detects a wide band sound from the measurement target. The acoustic sensor device according to claim 1, wherein a sound in a part of the predetermined band and a sound in the remaining band are detected.   The first characteristic sound indicates that the measurement target is normal, and the second characteristic sound indicates that the measurement target is abnormal. Acoustic sensor device. An acoustic diagnostic analyzer that detects, analyzes, and diagnoses at least a predetermined band of a wide band of sound from a measurement target,
A plurality of acoustic sensing elements that each include a vibrator that resonates in response to different sounds, and that is included in the wide band and that detects only sounds in different frequency bands;
An acoustic analysis diagnostic apparatus comprising: an analysis diagnostic unit that analyzes acoustic signals of different frequency bands output from the plurality of acoustic detection elements, diagnoses a sound distribution, and analyzes characteristics of the measurement target.   The acoustic analysis diagnostic apparatus according to claim 5, wherein the analysis / diagnosis unit analyzes normality / abnormality of the measurement target as the feature.   The acoustic analysis diagnosis apparatus according to claim 4, wherein the analysis / diagnosis unit determines whether or not the measurement target needs to be inspected and maintained according to the analysis of the abnormality detection. A method of manufacturing an acoustic sensor used for acoustic analysis of a measurement object,
Preparing a plurality of acoustic sensing elements including vibrators that resonate in response to different sounds;
Installing the plurality of acoustic detection elements in the vicinity of the measurement target, and collecting the data of the measurement target according to the purpose;
And a step of determining a combination of acoustic detection elements that resonate with sound in a predetermined band among the plurality of acoustic detection elements based on the collected data.

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