JPH0435716B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a sound source in which the sound generated from a sound source object is processed into a sound image, and the sound image and the object image of the sound source object are superimposed and visually displayed. It is related to exploration equipment.

[Prior Art] For example, when implementing noise countermeasures in machinery equipment, factories, etc., or when investigating and measuring the nature and loudness of sound, it is necessary to accurately detect the source of the noise. In order to easily and accurately probe and measure the position, size, spread, etc. of a sound source, the inventors have developed a sound source detection method using a sound collection device.

First, the principle of this sound source detection method is shown in FIG. That is, as shown in the figure, a sound source S is provided at a position P, and a reflection type sound collector D having a concave curved shape such as a paraboloid of revolution or a concave spherical surface is provided at a distance L from this position P. When placed towards the sound source S,
The sound from the sound source S is reflected by the reflective surface r of the sound collector D, and a sound image S' is formed at a position P'.
Therefore, if a microphone array in which a large number of microphones are arranged side by side in a matrix is placed facing the reflecting surface r at the sound image forming position P', even if the sound source object is large, the sound pressure distribution on the microphone array can be adjusted. It will be possible to output it as a sound image.

The sound image obtained in this way may be displayed in an analog manner as the difference in brightness of each light emitting diode in a light emitting diode array, for example, in which light emitting diodes are arranged in correspondence with each microphone constituting the microphone array. By digitizing the signals from the microphone array and displaying them as contour lines for each sound pressure level, it becomes possible to visually display a sound image. Furthermore, in order to superimpose and display this sound image on the object image of the sound source object, an object image capturing device consisting of a camera, a TV camera, etc. is used, and the object image of the sound source object is captured by the object image capturing device, and the object image of the sound source object is captured. By displaying the image superimposed on the sound image, the source position and sound pressure distribution of the noise in the sound source object can be displayed in correspondence with each constituent part of the sound source object to be searched, making sound source exploration easier and more efficient. Be able to do it with precision.

[Problems to be Solved by the Invention] However, when configuring the sound source detection device as described above to perform sound source detection of a sound source object,
It is necessary to accurately match the sound image and object image.
For example, if the field of view between the sound image and the object image is misaligned, it becomes impossible to accurately superimpose the two images, which reduces the accuracy of sound source detection.

The present invention has been made in view of the above points, and an object of the present invention is to provide a sound source detection device that can accurately superimpose and display a sound image and an object image. .

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention disposes a sound collector having a concave curved surface such as a paraboloid of revolution or a concave spherical surface toward a sound source object. A microphone array formed by arranging a large number of microphones in a matrix is disposed opposite to a sound collector, and a sound image is formed by receiving reflected sound from the sound collector on the microphone array. In a sound source detection device that captures an object image of a sound source object by an object image capturing device and displays the object image and the sound image in a superimposed manner, the microphone array and the object image capturing device are connected to the sound collector. On the mirror axis, a microphone array is arranged to face the sound collector side, an object image pickup device is arranged to face the sound source object side, and a focal plane of the object image pickup device is provided at a position close to the microphone array. It is characterized by the following.

[Function] As mentioned above, both the microphone array and the object image pickup device are arranged on the mirror axis of the sound collector, and the focal plane of the sound collector that functions as an acoustic lens and the optical lens are arranged on the mirror axis of the sound collector. Since it is located close to the focal plane of the object image pickup device,
It becomes possible to accurately match the field of view between the sound image and the object image. Therefore, by focusing the microphone array, which is the sound image forming surface of the sound collector, and also focusing the camera, TV camera, etc. that serves as the object image capturing device, the distance between the sound image and the object image can be accurately adjusted. can be matched,
The location of the noise, the sound pressure distribution, etc. in the sound source object are visualized and displayed in a state that corresponds accurately to each component, making it possible to search for the sound source and its distribution with high precision.

[Example] Hereinafter, an example of the present invention will be described in detail based on the drawings.

First, in FIGS. 1 and 2, reference numeral 1 indicates a sound collector having a concave curved shape such as a paraboloid of revolution or a concave spherical surface, and the surface side of the sound collector 1 contains noise from a sound source object. A reflective surface 1a is formed to reflect sound, and a microphone array 2 forming a focal plane for forming a sound image is disposed opposite to the reflective surface 1a. As shown in FIG. 3, the microphone array 2 is constructed by arranging a large number of microphones 2a in a matrix, each facing the reflecting surface 1a.
A sound absorbing material is interposed between the microphones 2a to prevent each microphone 2a from being affected by vibrations. The support plate 3 also includes a wiring box 4 that stores the wiring for each microphone 2a.
A bracket 5 is attached to the back of the wiring box 4, and a TV camera 6 constituting an object image pickup device for shooting an image of the sound source object toward the sound source object is attached to the bracket 5. There is.
In this way, by attaching the TV camera 6 to the back of the wiring box 4, the microphone array 2, which is the focal plane on which the sound image is formed, is placed close to the focal plane of the TV camera 6. has been done.

The sound collector 1 includes a core piece 7 that is circular in plan view, and a circumferential piece 8 that is formed by dividing an annular circumferential part surrounding the core piece 7 into a plurality of pieces at equal intervals in the radial direction. At the peripheral edges of the core piece 7 and the peripheral surface piece 8, there are joint parts 7a and 8 that protrude toward the back surface, respectively.
A is formed around the entire circumference of each. These pieces 7 and 8 are connected to each other with connecting parts 7a and 8a joined together, using a connecting member such as a hook or a bolt installed between these joint parts 7a and 8a or between joint parts 7a and 7a. It can be assembled by.

Next, as shown in FIG. 4, four mounting parts 9 are provided on the surface side of the core piece 7, and each mounting part 9 has four leg rods constituting the support frame 10. The support frame 10 is configured to be removably attached to the core piece 7 by engaging a hook 11 connected to the support frame 10a. The support frame 10 includes the four leg rods 10a described above, a connecting rod 10b that connects each pair of upper and lower leg rods 10a, and a bridging rod 10c that bridges between the connecting rods 10b. A guide member 12 is fixed to the connecting rod 10b, and a pedestal 13 on which an image receiving unit consisting of a microphone array 2, a support plate 3, a wiring box 4, and a TV camera 5 is mounted is attached to the guide member 12. The sound collector 1 can be reciprocated along the mirror axis C on the reflective surface 1a in a direction toward and away from the sound collector 1.

In order to move this pedestal 13, a screw shaft 14 is screwed into the pedestal 13. The screw shaft 14 passes through the core piece 7 and extends to the back side of the sound collector 1, and by screwing the screw shaft 14 from the back side of the sound collector 1, the image receiving unit can be mirrored. It is configured so that the focal position of the microphone array 2 can be adjusted by moving it along the axis C.

Furthermore, the leg rod 10a in the support frame 10
is made of a hollow member such as a metal pipe, into which the wiring cable 15 from the microphone array 2 and the TV camera 5 is inserted.
is configured to be connected to a terminal connecting portion 16 provided on the core piece 7.

Among the signals sent via the above-mentioned wiring cable 15, the signals from the microphone array 2 are input to the data processing device 17, which digitizes the sound signals received by each microphone 2a constituting the microphone array 2. The signal is converted into a signal related to contour lines for each sound pressure level within a predetermined range. The signal regarding the contour lines is configured to be input to a display device 18 consisting of a television monitor or the like, and the video signal of the object image from the TV camera 6 is input to the display device 18. ,
These signals related to the sound image and the signals related to the object image are displayed on the display device 18 in a superimposed state.

In the figure, 19 indicates a tripod, and 20 indicates a support member connected to the tripod 19, and the sound collector 1 is configured to be supported by the support member 20 attached to the tripod 19.

This embodiment is constructed as described above, and its operation will be explained next.

First, as shown in FIGS. 1 and 2, the sound collector 1 is assembled, and a support frame 10 is attached to the core piece 7 of the sound collector 1, and the support frame 10, which supports the image receiving unit consisting of the microphone array 2, the TV camera 6, etc., is mounted on the mounting portion 9 of the core piece 7. attached to the support member 18, and the reflective surface 1a of the sound collector 1.
Place it so that it points toward the sound source object. Here, since the microphone array 2 and the TV camera 6 are installed on the mirror axis C of the sound collector 1, the optical axis of the TV camera 6 is located on the mirror axis C. Moreover, since the focal plane of the TV camera 6 is located close to the microphone array 2, the image field ranges of the sound image and the object image are maintained in the same state. Therefore, by appropriately turning the screw shaft 14, the focus of the microphone array 2 is adjusted, and the focus of the TV camera 6 is also adjusted to bring the sound image and the object image into focus.

Therefore, when a sound is generated from a sound source object, this sound is reflected on the reflective surface 1a of the sound collector 1 and is received by each microphone 2a constituting the microphone array 2. converted into an electrical signal. This electrical signal is taken out via the wiring cable 15, inputted to the data processing device 17, and subjected to signal processing to form a sound image. This signal processing consists of forming data regarding the sound pressure for each predetermined level range, data regarding the peak value of the sound pressure, etc., and forming the above-mentioned data for each frequency. By processing the data in this manner, a sound image having desired properties is formed, and this sound image is displayed on the display device 18.
It will be visualized and displayed. At the same time, a video signal of the object image of the sound source object from the TV camera 6 is input to the display device 18, and the object image of the sound source object is displayed superimposed on the aforementioned sound image.

As described above, since the sound image from the sound source object and the object image are in a completely coincident state on the display device 18, the sound pressure level of the sound generated from the sound source object can be calculated from each constituent member of the sound source object. This makes it possible to visualize and display the sound in a state that accurately corresponds to the sound source, making it possible to perform highly accurate sound source detection.

Since the position of the sound image forming plane differs depending on the distance between the sound collector 1 and the sound source object, the microphone array 2 that forms the sound image is placed on the sound collector 1 along the mirror axis C. It is necessary to focus by moving the microphone array 2 toward or away from the object, and moving the microphone array 2 in this way changes the angle of view of the sound image. 6
The angle of view also changes depending on the distance between the sound source object and the TV camera 6, and since the focal plane of the TV camera 6 and the microphone array 6 are located close to each other, There is almost no difference in the angle of view, and therefore the sound image and the object image can be accurately superimposed regardless of the distance between the sound source object to be searched and the sound collection device. become.

[Effects of the Invention] As explained in detail above, the sound source detection device according to the present invention places the microphone array that forms a sound image and the object image pickup device on the mirror axis of the sound collector, and aligns the focal planes of each other. Since the sound image and the object image are arranged in close proximity to each other, it is possible to display the sound image and the object image in a superimposed manner with great accuracy, and the accuracy of sound source detection is significantly improved.

[Brief explanation of drawings]

1 to 4 show an embodiment of the present invention, in which FIG. 1 is an external view showing the overall configuration of a sound source detection device, FIG. 2 is a front view of FIG. 1, and FIG. 3 is a microphone A front view of the array, FIG. 4 is an external view of the image receiving unit,
FIG. 5 is an explanatory diagram of the principle of the sound collection type sound source detection method. 1: Sound collector, 1a: Reflective surface, 2: Microphone array, 2a: Microphone, 6: TV camera, 1
4: screw shaft, 17: data processing device, 18: display device.

Claims (1)

[Scope of Claims] 1. A microphone in which a sound collector having a concave curved surface such as a paraboloid of revolution or a concave sphere is arranged to face a sound source object, and a number of microphones are arranged in a matrix on the sound collector. arranging arrays facing each other, forming a sound image by receiving the reflected sound from the sound collector on the microphone array, and capturing an object image of the sound source object by an object image imaging device; In the sound source detection device that displays the object image and the sound image in a superimposed manner, the microphone array and the object image pickup device are placed on the mirror axis of the sound collector, and the microphone array is directed toward the sound collector, 1. A sound source detection device, characterized in that an object image pickup device is disposed facing toward a sound source object, and a focal plane of the object image pickup device is provided at a position close to the microphone array. 2. The microphone array and the object image pickup device are mounted on an image receiving unit, and the sound image on the microphone array is focused by reciprocating the image receiving unit along the mirror axis. A sound source searching device according to claim 1, characterized in that: