JPS63234117A - Movement type acoustic wattmeter - Google Patents

Abstract

PURPOSE:To detect a sound source and collect sound automatically in a short time with high accuracy while approaching the direction or position of the sound source by providing a moving mechanism which is controlled by using the arithmetic outputs of the direction and level of a sound flow. CONSTITUTION:A sensor part 1 is fitted to a support 2 consisting of hollow rods in a cross shape and this support 2 is fitted to a box-shaped main body part 3. An intensity arithmetic part 4 to which the sensor part 1 is connected and a control part 5 are stored in the main body part 3, a display part 6 is provided on the top surface of the main body part 3, and wheels 8a and 8b equipped with motors 7a and 7b for movement are provided on the main body part 3. Then the output signals of plural sensors are supplied to the arithmetic part 4 for intensity arithmetic and the direction and level of the sound flow are calculated in the plane which contains the plural sensors. Further, the control part 5, motor 7a and 7b for movement, and wheels 8a and 8b operate so as to move or rotate to the upstream side of the sound flow, and consequently the main body part moves so as to approach the sound source. Consequently, the position and level of the sound are detected automatically in a short time with high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an acoustic intensity wattmeter equipped with a plurality of sensor sections for sensing sound waves.

This invention relates to an acoustic intensity wattmeter with high efficiency and high precision acoustic exploration and sound collection functions.

[Conventional technology]

High-accuracy detection technology for noise sources is essential in order to implement noise countermeasures for equipment quickly and economically, and acoustic intensity wattmeters have recently attracted attention as a measuring device for this purpose.

Conventionally, this type of wattmeter has one
A device is known that includes a pair of sound wave sensor sections, a support section thereof, an intensity calculation section, and a display section that shows the magnitude and direction of the resulting intensity. That is, it is discussed in the document entitled "Simple Acoustic Intensity Meter" in IIS Leaflet-124 of the Institute of Industrial Science, the University of Tokyo.

[Problem that the invention seeks to solve]

The meter described in the above-mentioned prior art measures and displays the loudness and direction of the sound in the direction of an extended axis connecting a pair of sensors.When detecting the position and loudness of the sound source,
First, the sensor is rotated around the center of the pair of sensors to find the direction of the sound source, and then the wattmeter is moved in the direction of the sound source to detect the loudness of the sound. As described above, sound source detection is performed by performing the above two operations simultaneously or alternately while detecting the position and size of the sound source.

However, the above-mentioned conventional technology does not discuss the method of moving the wattmeter per rotation and the control method thereof, and there is a problem in that it requires a lot of time and effort to locate the sound source.

An object of the present invention is to provide a sound intensity wattmeter that can automatically and accurately detect the position and size of a sound source in a short time.

[Means for solving problems]

The above purpose is to incorporate a sensor section in which three or more sound wave detection sensors are arranged on the XY axis, an acoustic intensity calculation section 9 display section and control section, and a moving mechanism inside the main body, and to transmit the detection signals of the above sensors. By providing a moving mechanism that inputs the signal to the calculation unit, calculates the direction of the sound, or the direction and magnitude of the sound, and visually observes the signal, inputs this calculation signal to the control unit, and moves it in the upstream direction of the sound flow. achieved.

[Effect]

The intensity analysis section operates to calculate the intensity of the output signals of the plurality of sensors using the calculation section, and calculate the flow direction and magnitude of sound within a plane including the plurality of sensors.

Further, the moving section and the control section operate to move or rotate in the upstream direction of the sound flow. Since there is a sound source in the upstream direction of the sound flow, the moving unit moves sequentially to approach the sound source. As a result, the location and size of the sound source can be detected automatically with high precision and IM latency.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

FIG. 1 shows an external view of a mobile intensity wattmeter. In the wattmeter, a sensor section 1 is attached to a support 2 having a cross-shaped hollow bar, and the support 2 is attached to a box-shaped main body section 3. ing.

The main body section 3 includes an intensity calculation section 4 to which the sensor section 1 is connected. A control unit 5 is housed, and a display unit 6 is provided on the top surface of the main body.
However, wheels 8a and 8b equipped with moving motors 7a and 7b are also formed on the main body 3.

FIG. 2 shows the configuration of the sensor section. The sensor section includes an intensity measurement sensor 11 in the axial direction X portion of the support 2;
12 and sensors 13 and 14 for measuring the y-component in the direction perpendicular to the axis of the support 2.

Sensors 11 and 12 and sensors 13 and 14 face each other.

and are arranged so as to be perpendicular to each other. The sensors 11 and 12 are
These are small electret microphones (hereinafter referred to as microphones 11, 12, 13, and 14), and spacers 15 are provided to keep the distance between these microphones constant. Signals from each microphone are sent to the calculation unit 4 via thin wires 16.
to transmit the detection signal.

FIG. 3 shows an in-in-city calculation block, a display block, a control block, and a pulse motor block diagram. Outputs A and τ of microphones 11 and 12 and outputs B of the other pair of microphones 13 and 14.

(2) Buffer section 21 for amplification and impedance matching; a circuit 22 that calculates intensity components X and Y in the X and y directions from the A, τ and B and B signals; The circuit 23 includes a multiplication section 251 and a division section 26 for calculating the magnitude thereof, and circuits 27 and 28 for displaying the result on an LED. Further, from the output signal of the divider 26, a circuit 31 that calculates the angular difference between the support axis direction and the sound direction, a circuit 32 that calculates the rotation direction,
A gate circuit 34 for transmitting the output signal of the pulse oscillation return 33 to the drive circuit 34 of the step motor only for a time corresponding to the angular difference, and a wattmeter are equipped with an obstacle detection sensor 36 provided at its tip and a sound source. A control unit 30 consisting of a gate circuit 38 for transmitting the output signal of a pulse oscillator 37 to a step motor drive circuit 39 until the distance between certain structures approaches to within the set position and the sensor 36 is activated. With the output signals of these drive circuits 35 and 39,
It is composed of a pulse motor block 40 consisting of motors 41 and 42 for single rotation movement or running movement either or simultaneously.

In the intensity calculation section, the intensities Ix and Iy in the X and y directions can be expressed as the product of the sound pressure P (t) of the opposing microphone signal and the particle velocity V (t), respectively. Here, since the particle velocity V (t) is proportional to the spatial gradient of the sound pressure of the two microphone signals, the calculation shown in the following equation is realized by an electric circuit.

I v = P (t) V (t) where ρ is the density of space, Δrl and Δr2 are the distances between each pair of microphones, and P11 and P12 are the output sound pressures of the microphones 11 and 12.

The present invention has the above configuration, and the opposing microphone 1
1.12 and the microphone 13.1 perpendicular to this.
4, and synthesizes the magnitude and direction of the intensity in each pair of directions obtained using the microphone output signal of this thread path, and provides a display section that shows the propagation direction and magnitude of the sound wave. It has a configuration that includes a movement mechanism that is controlled using a calculation output in the direction of flow. As a result, the wattmeter provided with the moving mechanism approaches the sound source one after another, so that the position or position and size of the sound source can be automatically detected in a short time with high precision, and efficient sound source detection can be performed.

If an analog circuit, especially an analog filter such as a switched capacity filter is used in the calculation section, sound source detection for each frequency band becomes possible in real time.

The microphone shown in the above embodiment is an electret-type condenser microphone, which does not require a constant supply of DC voltage or a preamplifier for impedance conversion, making it more compact. Other types of microphones that can be configured as shown in FIG.

Furthermore, in this embodiment, an internal power supply section for driving an electric circuit is used in the arithmetic section box, and this power supply section is a dry battery or a rechargeable dry battery, but a power supply that can be driven from the outside is also included in the present invention.

Further, in the embodiment included in FIG. 2, a pair of microphones 11
and 12. 13 and 14 are provided to face each other, but depending on the shape and size of the space required for exploration, for example, two microphones may be placed in parallel with a pair of microphones placed orthogonally to this. It may be composed of a pair of microphones, and the arrangement of the microphones is set as appropriate. If directional accuracy of the sound flow is not required, two of the three microphones should be arranged in pairs, facing each other or in parallel, and the other one should be placed orthogonally to the two microphones mentioned above. The sensor for intensity measurement is formed by a total of two pairs of microphones arranged so as to form a pair with one other microphone and one of the two microphones forming the pair. Embodiments are also possible, and each modification of the arrangement of the microphones is also included in the present invention. Furthermore, in the above embodiment, the motor is a step motor, which can be driven with high precision by oven control, but
Any drive mechanism that can move the wattmeter, such as a town servo motor, will have the same effect. In addition, in this embodiment, the sensor section and the main body section are configured as one unit, but the same effect can be obtained even when the mobile wattmeter is divided and information is transmitted wirelessly. The wattmeter of this embodiment has the effect of making the moving part smaller and lighter.The wattmeter of this embodiment is used for both traveling and rotational driving, and an embodiment is shown in which the intensity calculation circuit is further provided. It is sufficient for the part to be a circuit that detects the direction of the flow of sound, and it is sufficient to use a circuit that detects the direction of sound flow, and for example, a circuit that only includes a rotation mechanism can be used to make the sound source on the extension of the axis of the support 2. A wattmeter may also be considered. Demonstrates highly efficient performance in sound collection work in halls and broadcast studios.
In addition, various modifications are possible by appropriately designing the movement mechanism depending on the shape and size of the movement space, such as designing a wattmeter with a mechanism that can move along the travel guide rail. also includes these modified structures.

Since each of the above-mentioned embodiments is equipped with a movement control section, the circuit of the wattmeter is complicated, but LSI integration technology makes it possible to reduce the size and power consumption, reducing the size of the conventional wattmeter to 1. ! There is almost no difference in quantity.

〔Effect of the invention〕

As explained above, according to the present invention, since the moving mechanism is provided which is controlled using the calculation output of the direction or direction and magnitude of the sound flow, it can sequentially approach the direction or position of the sound source and , has the effect of automatically detecting and collecting sound sources with high accuracy.

[Brief explanation of the drawing]

FIG. 1 is an external perspective view of a mobile acoustic wattmeter showing an embodiment of the present invention, FIG. 2 is a configuration diagram of the sensor section, and FIG. 3 is a display section of the calculation section 9 in the direction of sound flow. It is a block diagram showing the composition of a movement control part and a movement motor part. DESCRIPTION OF SYMBOLS 1... Sensor part, 2... Support, 4... Intensity calculation part, 5... Control part, 6... Display part, 7
a, 7b...movement motor, 8a, 8b...movement wheel, 11゜mo l 圀目Z 3 n

Claims (1)

[Claims] A sensor section in which one or more sound wave detection sensors are arranged on the XY axes, a sound intensity calculation section, a display section, a control section, and a moving mechanism are installed in the main body, A detection signal is input to a calculation unit, the direction of the sound or the direction and magnitude of the sound are calculated, and the sound is visually observed, and this calculation signal is input to the control unit, which is equipped with a moving mechanism that moves in the upstream direction of the sound flow. A mobile acoustic wattmeter characterized by: 2. The mobile sound intensity wattmeter according to claim 1, wherein the sound intensity calculation section includes a time domain calculation processing circuit. 3. The movement according to claim 1, wherein the sound wave detection sensor section and the movement mechanism are integrally provided via a sunport, and the intensity calculation section is inputted to the control device by wire or wirelessly. Acoustic wattmeter. 4. The mobile acoustic wattmeter according to claim 1, wherein the moving mechanism is provided with a mechanism capable of moving along a traveling guide.