JP2006201124A - Sound source position detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sound source position detector capable of detecting accurately a position of a sound source. <P>SOLUTION: This sound source position detector comprises a hood having, at least in an opening side, a rotation plane-shaped sound reflecting inner wall having an opening in its front end and a focal point in a rear side of the opening, and formed with an inner space; a vibration face arranged toward a front side in the hood; a sound receiving circuit for detecting vibration pressure on the vibration face caused by an incident sound from an outside; a directional information computing part for finding directional information expressing a direction of the center of the opening; a storage part for storing the vibration pressure detected by the sound receiving circuit, while correlated with the directional information in the time point when the vibration pressure is detected; a sound source specifying part for specifying the position of the sound source of the incident sound, using both the vibration pressure stored in the storage part and the directional information correlated with the vibration pressure; a photographing part for photographing the front side of the hood; an image processing part for processing an image photographed by the photographing part into an image indicating the position of the sound source specified by the sound source specifying part; and an image display part for displaying the image processed by the image processing part. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a sound source position detection device that detects the position of a sound source to be inspected.

  Conventionally, as a diagnostic method for mechanical equipment such as pumps, turbines, motors, and compressors used in manufacturing equipment such as steel, automobiles, petroleum, and chemical factories, abnormal sounds have been collected and analyzed. An acoustic method for determining the presence or absence is widely known.

  With regard to sound collection in this acoustic method, measurement point data in the measurement space can be obtained by scanning the microphone so as to trace the surface of the object to be diagnosed or by using a special microphone and device for measuring the sound intensity. A technique for collecting sap is known.

  However, the former has a drawback that it is difficult to apply to a large object, and the latter has a disadvantage that the measurement is troublesome and the apparatus is expensive.

  Therefore, as a simple and inexpensive technique, a technique for collecting sounds emitted from an inspection object with a microphone surrounded by a hood has been proposed by the present inventors (see Patent Document 1).

In this method, sound collection is performed while changing the direction of the hood so as to scan the inspection object.
Japanese Patent No. 3223237

  If sound is collected while changing the direction of the hood in this way, the position of the sound source can be understood to some extent, but there is a limit to accurately grasping the position.

  An object of this invention is to provide the sound source position detection apparatus which can detect the position of a sound source correctly in view of the said situation.

The sound source position detection apparatus of the present invention for achieving the above object is
A hood having an opening at the front end and a sound reflection inner wall having a rotating surface shape having a focal point behind the opening at least on the opening side, and an internal space formed;
A vibrating surface disposed forward in the hood;
A sound receiving circuit for detecting a vibration pressure of the vibration surface due to an incident sound from outside;
A direction information calculation unit for obtaining direction information indicating a direction in which the opening faces;
A storage unit that stores the vibration pressure detected by the sound receiving circuit in association with the direction information at the time of detecting the vibration pressure;
A sound source identifying unit that identifies the position of the sound source of the incident sound using both the vibration pressure stored in the storage unit and the direction information associated with the vibration pressure;
A photographing unit for photographing the front of the hood;
An image processing unit that processes an image captured by the imaging unit into an image representing a position of a sound source specified by the sound source specifying unit;
And an image display unit for displaying an image processed by the image processing unit.

  In the sound source position detection device of the present invention, the position of the sound source on the inspection object is specified, and the position of the sound source is displayed on the image obtained by photographing the inspection object by the photographing unit. Therefore, according to the sound source position detection apparatus of the present invention, the position of the sound source can be accurately grasped.

  Here, it is preferable that the image processing unit processes the image photographed by the photographing unit into an image showing a constant pressure line based on the vibration pressure of the vibration surface.

  In this way, the position of the sound source can be grasped more accurately.

  It is also a preferred aspect that the sound source position detection device of the present invention includes a light beam emitting unit that emits a light beam in a direction in which the opening faces.

  This is convenient as a guide for scanning the inspection object.

  According to the sound source position detection apparatus of the present invention, the position of the sound source can be accurately grasped.

  Hereinafter, embodiments of the present invention will be described.

  FIG. 1 is an external perspective view of an embodiment of a sound source position detection device of the present invention.

  FIG. 1A shows an external appearance of the sound source position detection device 1 from an oblique front, and FIG. 1B shows an external appearance of the sound source position detection device 1 from an oblique rear.

  A sound source position detection apparatus 1 shown in FIG. 1 includes a hood 11, a main body portion 12, and a handle portion 13.

  In addition, the sound source position detection device 1 shown in FIG. 1 includes a liquid crystal display screen 121f that displays an image on the back side of the main body 12, and an image obtained by photographing is displayed on the liquid crystal display screen 121f. It has become so.

  In addition, the sound source position detection device 1 shown in FIG. 1 allows the operator to recognize the direction in which the speaker 122c that emits the collected sound and the hood 11 are facing on the back side of the main body unit 12. A switch 123c that is operated when emitting a light beam is provided.

  Here, around the liquid crystal display screen 121f, a lock-on button 121k for determining a screen to be displayed on the liquid crystal display screen 121f, a zoom switch 121q for adjusting the zoom of the display image, and sound collection from the inspection target are collected. At the corresponding position on the screen display determined by the scanning start button 121m to be pressed at the start, the scanning end button 121n to be pressed at the end of the sound collection, and the lock-on button 121k, the vibration pressure detected corresponding to the position is represented by an isobaric line. A result display button 121p that is pressed to show is provided.

  FIG. 2 is a schematic cross-sectional view of an embodiment of a sound source position detection device of the present invention.

  FIG. 2 shows a hood 11 and a main body 12 having a sound reflection inner wall 11a constituting the sound source position detection device 1, and the main body 12 includes an imaging device 121, a sound processing unit 122, a light source device 123, and the like. It is comprised with the angular velocity sensor part 124. FIG.

  The imaging device 121 includes an imaging lens 121a, a zoom lens 121b, a focus lens 121c, a CCD 121d, a liquid crystal display panel 121f, and a CPU 121e that controls movement of the zoom lens 121b and the focus lens 121c. .

  The sound processing unit 122 includes a microphone 122a having a vibration surface 1221a, an amplifier 122b, and a speaker 122c. The microphone 122a detects vibration pressure as vibration pressure information on the vibration surface 1221a due to incident sound from the outside. is doing.

  The light source device 123 includes a light source 123a that emits a light beam, a power source 123b, and a switch 123c. By operating the switch 123c, a light beam that substantially matches the rotation axis of the sound reflection inner wall 11a of the hood 11 is emitted. It has come to be.

  The angular velocity sensor unit 124 includes two piezoelectric vibration gyros that detect angular velocities in directions orthogonal to each other, and an output signal as direction information from these piezoelectric vibration gyros is transmitted to the CPU 121e. ing.

  FIG. 3 is a block diagram of the configuration of the imaging device of the main body.

  3, in addition to the members shown in FIG. 2, the memory 121g, the image processing unit 121h, the LCD controller 121i, the first piezoelectric vibration gyro 124a for detecting the angular velocity in the vertical direction, and the angular velocity in the horizontal direction are detected. The second piezoelectric vibration gyro 124b, the lock on button 121k, the zoom button 121r, the scan start button 121m, the scan end button 121n, the result display button 121p, and the I / F 121j that transmits an operation to these buttons to the CPU 121e are described above. It is shown. A power switch 131 provided for the handle 13 shown in FIG. 1 is also shown.

  FIG. 4 is a diagram showing a part of the detection operation by the sound source position detection device.

  The sound source position detection operation in the sound source position detection apparatus 1 will be described below with reference to FIGS. 3 and 4 together.

  First, after operating the power switch 131, the switch 123c shown in FIG. 1 is operated to emit a light beam. This light beam is emitted substantially parallel to the rotation axis of the sound reflection inner wall surface 11a of the hood 11, and the direction of the hood opening can be easily recognized by irradiating the inspection object with this light beam. It has become. At the same time as the power is turned on, a through image centered on the portion irradiated with the light beam is displayed on the liquid crystal display screen 121f.

  Next, the inspection object is captured on the display screen, and the angle of view is determined by the zoom button 121q. When the angle of view is determined, the lock-on button 121k is pressed, and the currently displayed display image is stored in the memory 121g. At the same time that the lock-on button 121k is pressed, the CPU 121e sets the reference for detecting the angular velocity, so that the change in the direction of the hood relative to the direction of the hood when the lock-on is made can be recognized. become.

  A dotted line extending from the sound source position detection device 1 to the inspection target shown in FIG. 4 represents a light beam. FIG. 4A shows a central portion 100a of the scanning inspection target 100 when the lock-on button 121k is operated. A state in which the light beam is irradiated is shown.

  Next, when the detection of the sound generated from the inspection object is started, the hood is directed to the start point of the sound detection using the light beam. FIG. 4B shows a state in which the hood is directed to the upper right corner of the inspection target as a starting point.

  When starting the detection of the sound source position, the scan start button 121m is pressed. As a result, recording in which the direction information obtained by the two piezoelectric vibration gyros 124a and 124b and the vibration pressure information detected by the microphone 122a are associated with each other is started in the memory 121g. Until a predetermined time.

  Thereafter, when the scanning of the entire inspection object is completed, the scanning end button 121n is pressed. Thereby, the recording in which the direction information and the vibration pressure information are associated is stopped.

  Here, when the result display button 121p is pressed, the CPU 121e identifies the sound source from the direction information recorded in the memory 121g and the corresponding vibration pressure, that is, detects the direction information having the same vibration pressure. Thereafter, when the result display button 121p is pressed, the CPU 121e causes the image processing unit 121h to combine the image stored when the lock-on button 121k is pressed with the isobaric line corresponding to the position on the image. The composite image is displayed on the LCD 121f through the LCD controller 121i.

  FIG. 5 is a diagram in which isobaric lines representing vibration pressure are displayed on the image stored when the lock-on button is pressed.

  FIG. 5 shows a state in which the isobaric lines near the central portion 100a of the inspection object 100 are dense and there are places P1 and P2 with high vibration pressure.

  As described above, in the sound source position detection device 1 of the present embodiment, the detected direction information and vibration pressure are stored in association with each other, and the position of the sound source on the inspection target is determined based on the direction information. The position of the sound source is displayed with an isobaric line according to the vibration pressure on the image obtained by specifying the image of the inspection target. Therefore, according to the sound source position detection device 1 of the present embodiment, the position of the sound source can be accurately detected.

  Here, FIG. 6 is an external perspective view of another aspect of the embodiment shown in FIG.

  FIG. 6 shows a state in which the opening 111 is covered with a vinyl chloride sheet 200 cut to a size that can cover the opening 111 of the hood 11 with a margin. The vinyl chloride sheet 200 is attached so as to cover the opening 111 of the hood 11 in a state of being stretched by a frame 201 having a diameter slightly longer than the diameter of the opening 111 that can be fitted to the opening periphery of the hood 11. In addition, although the example using this vinyl chloride sheet 200 was given and demonstrated here, this vinyl chloride sheet 200 is arrange | positioned ahead of the vibration surface 1221a (refer FIG. 7), and this in the space in a hood. It may be a partition wall having sound permeability that isolates at least the rear region including the vibration surface 1221a from the outside of the hood.

  Further, in this aspect, the sound absorbing material 202 (see FIG. 7) surrounding the vibration surface 1221a is provided. When only the vinyl chloride sheet 200 is provided and the sound absorbing material 202 is not provided, the sound wave is generated by multiple reflections of sound waves between the sound reflection inner wall surface 11a (see FIG. 7) of the hood 11 and the vinyl chloride sheet 200 or the partition wall. The standing wave to be suppressed can be suppressed by providing the sound absorbing material 202 as in this aspect. In addition, in the conventional sound collector etc. in which the above-described sound absorbing material 202 is not provided, in order to suppress the occurrence of the standing wave described above, a tight sheet-like object or a partition is used as a cover for the hood opening. On the other hand, according to this aspect, the sound absorbing material 202 is provided, so that the sheet-like material and the partition walls that are tight can be used. For this reason, it is possible to prevent the sound collecting performance from being lowered due to the vinyl sheet or the like fluttering in the wind, and to prevent the vibration surface 1221a from being damaged.

  Furthermore, in this aspect, since the sound absorbing material 202 is formed in a shape surrounding the sound incident path to the vibration surface 1221a in the hood and the surface shape of the sound absorbing material 202 is uneven, the direct vibration surface The sound waves that reach the vibration surface 1221a after being reflected by the sound reflection inner wall 11a of the hood 11 without being attenuated despite being absorbed by the sound absorbing material 202 without being disturbed by the sound waves that reach the 1221a. It can be absorbed by the absorbent material 202. For this reason, it is possible to make interference between sound waves difficult to occur. Therefore, according to this aspect, it can also contribute to highly accurate acoustic analysis.

  FIG. 7 is a schematic cross-sectional view of the embodiment shown in FIG. 1 that is different from the embodiment shown in FIG.

  FIG. 7 shows a mode in which the sound absorbing material 203 is further arranged along the peripheral edge of the opening 111 of the hood 11 with respect to the mode shown in FIG. 6 of the sound source position detection device 1 shown in FIG. .

  With such an embodiment, it is possible to attenuate the sound wave that arrives from the side or rear of the hood 11 and is diffracted at the edge of the hood opening and enters the hood, so that high-accuracy acoustic analysis is possible. Can further contribute.

  In the embodiment described above, the direction information is obtained by the angular velocity sensor unit 124. However, for example, the direction information may be obtained based on an image photographed by the photographing unit without providing the angle sensor unit 124. Of course it is possible.

  In the above embodiments, the sound source is expressed by an isobaric line. However, the present invention is not limited to this, and the case where the sound source is detected on the inspection target using the light beam as a guide is taken as an example. Although mentioned, even if this is not provided in the present invention, the basic effect is not reduced.

It is an external appearance perspective view of one Embodiment of the sound source position detection apparatus of this invention. It is a schematic sectional drawing of one Embodiment of the sound source position detection apparatus of this invention. It is a block diagram of the configuration of the imaging device of the main body. It is a figure which shows a part of detection operation by this sound source position detection apparatus. It is the figure which displayed the isobar which represents a vibration pressure on the image memorize | stored when the lock-on button was pressed down. It is an external appearance perspective view of another aspect of embodiment shown in FIG. It is a schematic sectional drawing of the aspect different from the aspect shown in FIG. 6 of embodiment shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sound source position detection apparatus 11 Hood 12 Main body part 121a Imaging lens 121b Zoom lens 121c Focus lens 121d CCD
121f Liquid crystal display screen 121e CPU
121g Memory 121h Image processing unit 121i LCD controller 121k Lock on button 121q Zoom switch 121m Scan start button 121n Scan end button 121p Result display button 122 Sound processing unit 123 Light source device 124 Angular velocity sensor unit 200 Vinyl chloride sheet 201 Frame 202, 203 Sound absorbing material

Claims (3)

A hood having an opening at the front end and a sound reflection inner wall having a rotating surface shape having a focal point behind the opening at least on the opening side, and an internal space formed;
A vibrating surface disposed forward in the hood;
A sound receiving circuit for detecting a vibration pressure of the vibration surface due to an incident sound from outside;
A direction information calculation unit for obtaining direction information indicating a direction in which the opening faces;
A storage unit that stores the vibration pressure detected by the sound receiving circuit in association with the direction information at the time of detecting the vibration pressure;
A sound source identifying unit that identifies the position of the sound source of the incident sound using both the vibration pressure stored in the storage unit and the direction information associated with the vibration pressure;
A photographing unit for photographing the front of the hood;
An image processing unit that processes an image captured by the imaging unit into an image representing a position of a sound source specified by the sound source specifying unit;
A sound source position detection apparatus comprising: an image display unit that displays an image processed by the image processing unit.   The sound source position detection device according to claim 1, wherein the image processing unit processes the image captured by the imaging unit into an image showing a constant pressure line based on a vibration pressure of the vibration surface.   The sound source position detecting device according to claim 1, further comprising a light beam emitting unit that emits a light beam in a direction in which the opening faces.

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