Surface sound pressure measurement system and surface sound pressure measurement method

Abstract

To efficiently measure sound pressure levels on the surface of building materials. [Solution] The surface sound pressure measurement system comprises a sound receiving unit formed by integrating a microphone and a distance meter, a microphone moving device that supports the sound receiving unit so as to be movable in opposition to a building material installed as a target for evaluation of sound insulation performance, and a measurement control device that controls the sound receiving unit and the microphone moving device. The measurement control device comprises an acquisition unit that acquires a measurement value of the distance from the sound receiving unit to the building material measured by the distance meter, a calculation unit that calculates the amount of movement of the sound receiving unit from its current position to a predetermined measurement position based on the measurement value acquired by the acquisition unit, a movement control unit that instructs the microphone moving device to move the sound receiving unit by the amount of movement calculated by the calculation unit, and a sound pressure level calculation unit that calculates the surface sound pressure level of the building material from the sound waveform received by the sound receiving unit after the movement.

Description

Technical Field

[0001] The present invention relates to a surface sound pressure measurement system and a surface sound pressure measurement method.

Background Art

[0002] Conventionally, when evaluating the sound insulation performance of building materials such as window glass and wall materials, for example, the building material is placed at an opening connecting a reverberation chamber and an anechoic chamber to partition the reverberation chamber and the anechoic chamber, and the power of the sound emitted from a speaker installed in the anechoic chamber is measured in the reverberation chamber. The sound insulation performance of the building material can be expressed, for example, by the following formula (1) as the acoustic transmission loss R depending on the incident angle θ of the sound on the building material. R(θ)=SWL inc (θ)-SWL trans (θ) ···(1) However, in formula (1), SWL inc represents the power level of the sound incident on the building material, and SWL trans represents the power level of the sound transmitted through the building material.

[0003] The power level SWL of the sound incident on the building material inc can be measured using a microphone for the sound pressure level on the surface of the building material (hereinafter referred to as "surface sound pressure level"), and can be calculated from the measured surface sound pressure level. Specifically, for example, assuming that the sound wave incident on the building material is a plane wave and the building material is rigid, the following formula (2) holds between the surface sound pressure level L s,1 of the building material and the power level SWL inc of the sound incident on the building material. SWL inc =L s,1 +10log 10 (Scosθ)-6 ···(2) However, in formula (2), S represents the area of the building material.

[0004] By the way, when the surface of the test body on which the sound wave is incident is flat and the area is infinitely large, theoretically, when a plane wave is incident on this test body, the surface sound pressure level L s,1L is constant regardless of position. However, in reality, the sound waves radiated from a speaker are not plane waves, and due to factors such as the finite surface area of ​​the building material, the surface sound pressure level L of the building material is constant. s,1 This varies depending on the location. Therefore, the surface sound pressure level L of the building material. s,1 When measuring, do not measure at only one point, but measure the surface sound pressure level L at multiple locations. s,1 By measuring the sound at each location and taking the average of the measurements, the power level of the sound incident on the building material can sometimes be determined.

[0005] Also, surface sound pressure level L s,1 Since this also varies depending on the angle of incidence θ of the sound incident on the building material, the surface sound pressure level L is determined by changing the angle of incidence θ at each position. s,1 Sometimes, the surface sound pressure level L is measured. s,1 The measurement process requires repeated steps while moving the microphone and speaker, and there is a need to improve the efficiency of the measurement.

[0006] Furthermore, the surface sound pressure level L s,1 When taking measurements, the microphone is placed a few millimeters away from the surface of the building material. However, manually placing the microphone at each of the numerous measurement points is difficult, so it is conceivable to use a mobile device that automatically moves the microphone to a specified coordinate position. However, since the surface of the building material is not always flat, and the orientation of the building material is not always vertical or horizontal, it is not easy to specify coordinates so that the microphone is moved to a constant distance from the surface of the building material. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Publication No. 62-165531 [Patent Document 2] Japanese Patent Publication No. 2006-113037 [Patent Document 3] Japanese Patent Publication No. 2006-266959 [Overview of the project] [Problems that the invention aims to solve]

[0008] The object of the present invention is to provide a surface sound pressure measurement system and a surface sound pressure measurement method that can efficiently measure the sound pressure level on the surface of building materials. [Means for solving the problem]

[0009] According to one aspect of the present invention, a surface sound pressure measurement system includes a sound receiving unit formed by integrating a microphone and a distance meter, a microphone moving device that movably supports the sound receiving unit facing a building material installed as a target for evaluation of sound insulation performance, and a measurement control device that controls the sound receiving unit and the microphone moving device, wherein the measurement control device includes an acquisition unit that acquires a measurement value of the distance from the sound receiving unit to the building material measured by the distance meter, a calculation unit that calculates the amount of movement of the sound receiving unit from its current position to a predetermined measurement position based on the measurement value acquired by the acquisition unit, a movement control unit that instructs the microphone moving device to move the sound receiving unit by the amount of movement calculated by the calculation unit, and a sound pressure level calculation unit that calculates the surface sound pressure level of the building material from the sound waveform received by the sound receiving unit after the movement.

[0010] This configuration allows the microphone to be easily moved to a constant distance from the surface of the building material, enabling efficient measurement of surface sound pressure levels at multiple measurement locations. In other words, it allows for efficient measurement of sound pressure levels on the surface of the building material.

[0011] Furthermore, according to another aspect of the present invention, in the above configuration, the sound receiving unit is formed by integrating an ultrasonic distance meter for measuring the distance to the building material by ultrasonic waves with the microphone.

[0012] This configuration allows for the measurement of the distance to building materials, even transparent window glass, and enables efficient measurement of the surface sound pressure level of transparent building materials.

[0013] Also, according to another aspect of the present invention, in the above configuration, after the acquisition unit moves the sound receiving unit parallel to the surface of the building material to a position corresponding to the predetermined measurement position, the acquisition unit acquires the measurement value obtained by the distance meter.

[0014] According to this configuration, since the distance between the microphone and the building material is accurately set at the actual measurement position, the microphone can be arranged at an accurate measurement position regardless of the unevenness of the surface of the building material or the posture in which the building material is installed.

[0015] Also, according to another aspect of the present invention, in the above configuration, the measurement control device further includes a correction value storage unit that stores a correction value obtained from the measurement value obtained by the distance meter and the moving distance of the sound receiving unit by the microphone moving device, and that cancels out the measurement error included in the measurement value obtained by the distance meter, and a correction control unit that corrects the measurement value acquired by the acquisition unit using the correction value stored by the correction value storage unit. The calculation unit calculates the amount of movement from the current position of the sound receiving unit to a predetermined measurement position based on the measurement value after correction by the correction control unit.

[0016] According to this configuration, even when using an ultrasonic distance meter with relatively low accuracy, the microphone can be accurately moved to a certain distance from the surface of the building material, and the surface sound pressure level at a plurality of measurement positions can be efficiently measured.

[0017] Also, according to another aspect of the present invention, in the above configuration, the surface sound pressure measurement system further includes a speaker moving device that movably supports a speaker that radiates sound toward the building material, and the sound receiving unit receives the sound radiated from the speaker by the microphone.

[0018] According to this configuration, the surface sound pressure level of the building material can be measured while changing the incident angle of the sound to the building material by moving the speaker.

[0019] Furthermore, according to another aspect of the present invention, a surface sound pressure measurement method is performed by a surface sound pressure measurement system having a sound receiving unit formed by integrating a microphone and a distance meter, a microphone moving device that movably supports the sound receiving unit facing a building material installed as a target for evaluation of sound insulation performance, and a measurement control device that controls the sound receiving unit and the microphone moving device, wherein the measurement control device acquires a measurement value of the distance from the sound receiving unit to the building material by the distance meter, calculates the amount of movement of the sound receiving unit from its current position to a predetermined measurement position based on the acquired measurement value, instructs the microphone moving device to move the sound receiving unit by the calculated amount of movement, and calculates the surface sound pressure level of the building material from the sound waveform received by the sound receiving unit after the movement.

[0020] This method allows the microphone to be easily moved to a constant distance from the surface of the building material, enabling efficient measurement of surface sound pressure levels at multiple measurement locations. In other words, it allows for efficient measurement of sound pressure levels on the surface of the building material. [Effects of the Invention]

[0021] According to the present invention, the sound pressure level on the surface of building materials can be measured efficiently. [Brief explanation of the drawing]

[0022] [Figure 1] Figure 1 is a diagram showing the schematic configuration of the surface sound pressure measurement system according to Embodiment 1. [Figure 2] Figure 2 shows the configuration of the sound receiving section. [Figure 3] Figure 3 is a block diagram showing the configuration of the measurement control device according to Embodiment 1. [Figure 4] Figure 4 is a sequence diagram showing the surface sound pressure measurement method according to Embodiment 1. [Figure 5] Figure 5 is a block diagram showing the configuration of the measurement control device according to Embodiment 2. [Figure 6] Figure 6 is a flowchart illustrating the calibration process. [Figure 7] Figure 7 is a sequence diagram showing the surface sound pressure measurement method according to Embodiment 2. [Modes for carrying out the invention]

[0023] Embodiments of the present invention will be described below with reference to the attached drawings. The embodiments described below are illustrative and should not be interpreted as limiting.

[0024] (Embodiment 1) Figure 1 is a diagram showing the schematic configuration of a surface sound pressure measurement system according to Embodiment 1. The surface sound pressure measurement system shown in the figure measures the sound pressure level on the surface of a building material 30 installed at the boundary between the anechoic chamber 10 and the reverberation chamber 20 in order to evaluate the sound insulation performance of the building material 30. In this surface sound pressure measurement system, the anechoic chamber 10 and the reverberation chamber 20 are defined by placing the building material 30 in the opening that connects the anechoic chamber 10 and the reverberation chamber 20.

[0025] The anechoic chamber 10 is a room in which the walls, ceiling, and floor are covered with sound-absorbing material, and there is no sound reflection. A speaker relocation device 11, a speaker 12, a microphone relocation device 13, and a sound receiving unit 200 are arranged inside the anechoic chamber 10.

[0026] The reverberation chamber 20 is a room in which sound is reflected, as its walls, ceiling, and floor are made of reflective materials. Multiple microphones 21 are placed inside the reverberation chamber 20.

[0027] The building material 30 is a component whose sound insulation performance is evaluated, such as window glass or wall material. The building material 30 generally has a flat plate shape and is installed in the opening connecting the anechoic chamber 10 and the reverberation chamber 20, thereby shielding this opening. In other words, by installing the building material 30 in the opening, the anechoic chamber 10 and the reverberation chamber 20 are defined with the building material 30 as the boundary.

[0028] The speaker repositioning device 11 has a semicircular shape in side view and supports the speaker 12 so that it can move along the inside of the arc. The speaker repositioning device 11 is also mounted on the wall of the anechoic chamber 10 so that it can rotate around a string connecting the two ends of the arc as the axis of rotation. In other words, the speaker repositioning device 11 moves the position of the speaker 12 relative to the building material 30 so that the angle of incidence at which sound radiated from the speaker 12 enters the building material 30 can be changed.

[0029] The speaker 12 radiates sound of a predetermined sound source waveform toward the building material 30. The sound radiated from the speaker 12 is partially blocked by the building material 30 and then transmitted to the reverberation chamber 20.

[0030] The microphone moving device 13 supports a sound-receiving unit 200, which is equipped with a microphone facing the building material 30, so that it can move relative to the surface of the building material 30. Specifically, the microphone moving device 13 has a base that is slidably attached to a rail provided on the lower part of the wall surface of the anechoic chamber 10, a support column extending upward from the base, and a support arm that is provided so as to be movable vertically along the support column and supports the sound-receiving unit 200 so as to be able to adjust the distance between it and the building material 30. The microphone moving device 13 moves the sound-receiving unit 200 horizontally (depth direction with respect to the paper) by sliding the base on the rail. The microphone moving device 13 also moves the sound-receiving unit 200 vertically by moving the support arm vertically along the support column. Furthermore, the microphone moving device 13 moves the sound-receiving unit 200 in a direction (left-right direction with respect to the paper) toward or toward the building material 30 by the distance adjustment mechanism of the support arm. In the following, the horizontal direction (depth direction with respect to the paper) will also be referred to as the "X direction," the vertical direction as the "Y direction," and the direction of approaching or moving away from the building material 30 (left and right direction with respect to the paper) as the "Z direction."

[0031] Microphones 21 are placed at multiple different locations within the reverberation chamber 20 to receive sound entering the reverberation chamber 20 from the anechoic chamber 10 through the building materials 30. The power level of the sound passing through the building materials 30 is calculated from the sound pressure level of the sound received by microphones 21.

[0032] The measurement control device 100 is connected to the speaker relocation device 11, speaker 12, microphone relocation device 13, and sound receiving unit 200 of the anechoic chamber 10, and controls each of these devices to measure the sound pressure level (surface sound pressure level) on the surface of the building material 30. The specific configuration and operation of the measurement control device 100 will be described in detail later.

[0033] The sound receiving unit 200 is formed by integrating a microphone and an ultrasonic rangefinder, and receives sound emitted from the speaker 12 using the microphone. The sound receiving unit 200 also measures the distance between the building material 30 and the microphone using the ultrasonic rangefinder in order to adjust the distance between the building material 30 and the microphone. Specifically, the sound receiving unit 200 has a configuration as shown in Figure 2, for example.

[0034] As shown in Figure 2, the sound receiving unit 200 is formed by fixing a microphone 210 and an ultrasonic distance meter 220 to each other and is supported by a support arm 13b provided on the support column 13a of the microphone moving device 13. The tip of the microphone 210 facing the surface of the building material 30 and the tip of the transducer 220a of the ultrasonic distance meter 220 are aligned in the Z direction, and the distance measurement by the ultrasonic distance meter 220 is equal to the distance between the tip of the microphone 210 and the building material 30. However, the tip of the microphone 210 and the tip of the transducer 220a of the ultrasonic distance meter 220 do not necessarily have to be in the same position in the Z direction, and a predetermined offset may be provided between the positions of their respective tips. That is, for example, the tip of the transducer 220a may protrude by a predetermined length beyond the tip of the microphone 210, or the tip of the microphone 210 may protrude by a predetermined length beyond the tip of the transducer 220a.

[0035] The microphone 210 receives sound radiated from the speaker 12 in the anechoic chamber 10 from its tip and outputs the received sound waveform to the measurement control device 100. In other words, the microphone 210 receives sound from the speaker 12 near the surface of the building material 30 in order to acquire the surface sound pressure level of the building material 30.

[0036] The ultrasonic distance meter 220 receives ultrasonic waves emitted from the transmitter / receiver 220a and reflected from the building material 30, and measures the distance between the tip of the transmitter / receiver 220a and the building material 30 based on the time taken from emission to reception. The ultrasonic distance meter 220 then outputs the measured distance to the measurement control device 100.

[0037] The sound-receiving unit 200, which includes a microphone 210 and an ultrasonic rangefinder 220, is supported by a support arm 13b, and the distance between the tip of the microphone 210 and the building material 30 is adjusted by a distance adjustment mechanism in the Z direction of the support arm 13b. Furthermore, the support arm 13b that supports the sound-receiving unit 200 is movable in the Y direction along a support column 13a, and the support column 13a is movable in the X direction as its base slides along a rail. Therefore, the sound-receiving unit 200 can be moved arbitrarily in the X, Y, and Z directions by the microphone moving device 13.

[0038] Figure 3 is a block diagram showing the configuration of the measurement control device 100 according to Embodiment 1. The measurement control device 100 shown in Figure 3 includes a measurement instruction unit 102, a microphone movement control unit 104, a measurement value acquisition unit 106, a Z movement amount calculation unit 108, a microphone control unit 110, a speaker movement control unit 112, a speaker control unit 114, a sound pressure level calculation unit 116, an incident power calculation unit 118, and an incident power storage unit 120.

[0039] When measuring the surface sound pressure level of the building material 30, the measurement instruction unit 102 notifies the microphone movement control unit 104 and the speaker movement control unit 112 of the destination positions of the microphone 210 and speaker 12, respectively. That is, since the surface sound pressure level of the building material 30 is measured at various measurement positions near the surface of the building material 30 while changing the angle of incidence of sound to the building material 30, the measurement instruction unit 102 instructs the speaker movement control unit 112 to move the speaker 12 to a position corresponding to the angle of incidence of sound, and instructs the microphone movement control unit 104 to move the microphone 210 to each measurement position. For the measurement position of the microphone 210, the measurement instruction unit 102 specifies the XY coordinates of the measurement position and the distance from the building material 30.

[0040] When the measurement position of the microphone 210 is instructed, the microphone movement control unit 104 calculates the amount of movement in the X and Y directions from the current position of the microphone 210 to the instructed measurement position, and outputs the calculated amount of movement to the microphone movement device 13. Then, after the microphone 210 has moved parallel to the surface of the building material 30 to the XY coordinates of the measurement position, when the amount of movement in the Z direction is notified by the Z movement amount calculation unit 108, the microphone movement control unit 104 outputs the notified amount of movement in the Z direction to the microphone movement device 13.

[0041] When the microphone 210 is moved to the XY coordinates of the measurement position by the microphone moving device 13, the measurement value acquisition unit 106 acquires the measurement value of the distance to the building material 30 measured by the ultrasonic distance meter 220. In other words, the measurement value acquisition unit 106 acquires the measurement value of the distance in the Z direction from the tip of the microphone 210 to the building material 30.

[0042] The Z-movement calculation unit 108 calculates the amount of Z-movement of the microphone 210 to the specified measurement position based on the measured distance in the Z-direction from the tip of the microphone 210 to the building material 30, and notifies the microphone movement control unit 104 of the calculated amount of Z-movement. In other words, the Z-movement calculation unit 108 calculates the amount of Z-movement of the microphone 210 so that the distance from the tip of the microphone 210 to the building material 30 becomes the specified distance.

[0043] When the microphone movement control unit 104 outputs a movement amount and the microphone 210 moves to the measurement position, the microphone control unit 110 acquires the sound waveform received by the microphone 210. The microphone control unit 110 then outputs the acquired sound waveform to the sound pressure level calculation unit 116.

[0044] When the speaker movement control unit 112 receives an instruction from the measurement instruction unit 102 for the destination position of the speaker 12, it calculates the amount of movement from the speaker 12's current position to the instructed destination position and outputs the calculated amount of movement to the speaker movement device 11.

[0045] When the speaker movement control unit 112 outputs a movement amount and the speaker 12 moves to the destination, the speaker control unit 114 outputs a pre-stored sound source waveform to the speaker 12, causing the speaker 12 to emit sound.

[0046] The sound pressure level calculation unit 116 calculates the surface sound pressure level of the building material 30 based on the received sound waveform acquired by the microphone control unit 110. The sound pressure level calculation unit 116 calculates the surface sound pressure level at multiple measurement positions of the microphone 210 for each of multiple angles of sound incidence to the building material 30.

[0047] The incident power calculation unit 118 calculates the power level of the sound incident on the building material 30 (hereinafter referred to as "incident power level") for each incident angle, based on the surface sound pressure levels calculated for multiple measurement positions of the microphone 210.

[0048] The incident power storage unit 120 stores the incident power level calculated by the incident power calculation unit 118, associating it with the angle of incidence of sound to the building material 30. From the incident power level stored in the incident power storage unit 120 and the power level of sound transmitted through the reverberation chamber 20, the sound transmission loss can be determined as the sound insulation performance of the building material 30.

[0049] Next, the surface sound pressure measurement method using the surface sound pressure measurement system configured as described above will be explained with reference to the sequence diagram shown in Figure 4.

[0050] Once the angle of incidence of sound onto the building material 30 and the measurement position of the microphone 210 for measuring the surface sound pressure level are determined from predetermined measurement conditions, the measurement control device 100 instructs the speaker moving device 11 to move the speaker 12 to the destination corresponding to the angle of incidence (step S101). Specifically, the amount of movement from the speaker 12's current position to the destination position corresponding to the angle of incidence is output to the speaker moving device 11. The speaker moving device 11 then moves the speaker 12 according to this amount of movement, and the speaker 12 is positioned so that it can radiate sound onto the building material 30 at the angle of incidence specified in the measurement conditions.

[0051] Furthermore, the measurement control device 100 instructs the microphone moving device 13 to move the microphone 210 to the XY coordinates of the determined measurement position (step S102). Specifically, the amount of movement in the X and Y directions from the current position of the microphone 210 to the measurement position is output to the microphone moving device 13. Then, according to this amount of movement, the microphone moving device 13 moves the microphone 210 parallel to the surface of the building material 30, and the microphone 210 is positioned at the XY coordinates of the measurement position. At this time, since the microphone 210 moves parallel to the surface of the building material 30 and does not move in the Z direction, the distance between the tip of the microphone 210 and the building material 30 is not the distance corresponding to the measurement position.

[0052] When the microphone 210 moves to the XY coordinates of the measurement position, the measurement control device 100 instructs the ultrasonic distance meter 220 to measure the distance to the building material 30 (step S103). Upon receiving this instruction, the ultrasonic distance meter 220 measures the distance to the building material 30 (step S104), and the measured value is output to the measurement control device 100 (step S105). Here, since the distance is measured by the ultrasonic distance meter 220, even if the building material 30 is, for example, a transparent window glass that does not reflect the laser of a laser distance meter, the distance to the building material 30 can be measured by the reflection of ultrasonic waves. Also, since the microphone 210 and the ultrasonic distance meter 220 form a sound receiving unit 200 as a whole, the distance measurement output from the ultrasonic distance meter 220 corresponds to the distance between the tip of the microphone 210 and the building material 30.

[0053] Then, when the measurement control device 100 acquires a distance measurement, the amount of movement in the Z direction required to move the microphone 210 to the measurement position is calculated based on the distance measurement (step S106), and the calculated amount of movement is output to the microphone moving device 13 (step S107). The microphone 210 is then moved by the microphone moving device 13 according to this amount of movement, and the distance between the tip of the microphone 210 and the building material 30 becomes the distance corresponding to the measurement position.

[0054] In this way, the microphone 210 and the ultrasonic rangefinder 220 form a single sound receiving unit 200, and the position of the microphone 210 in the Z direction is adjusted based on the distance measurement to the building material 30 by the ultrasonic rangefinder 220, so that the distance between the tip of the microphone 210 and the building material 30 can be set accurately and easily. That is, even if, for example, the surface of the building material 30 is not flat but uneven, or if the building material 30 is installed in an inclined position, the tip of the microphone 210 can be moved to a constant distance from the surface of the building material 30.

[0055] Then, in order to confirm that the microphone 210 is in the correct measurement position, the measurement control device 100 instructs the ultrasonic distance meter 220 to measure the distance to the building material 30 again (step S108). Upon receiving this instruction, the ultrasonic distance meter 220 measures the distance to the building material 30 (step S109), and the measured value is output to the measurement control device 100 (step S110). Once the distance measurement is acquired by the measurement control device 100, it is confirmed whether the distance between the tip of the microphone 210 and the building material 30 is in accordance with the measurement position.

[0056] Note that the verification of whether the microphone 210 is correctly positioned for measurement may be omitted, and if this verification is omitted, the operations in steps S108 to S110 described above will not be performed.

[0057] As a result of the operations performed so far, the speaker 12 and microphone 210 are positioned for measuring the surface sound pressure level. The measurement control device 100 controls the speaker 12 and microphone 210 so that the speaker 12 emits sound and the microphone 210 receives this sound (step S111). Once the received waveform is acquired by the microphone 210, the measurement control device 100 calculates the surface sound pressure level from the received waveform (step S112). This provides the surface sound pressure level at one measurement position. However, it is preferable to measure the surface sound pressure level at multiple measurement positions. Therefore, if the microphone 210 is moved to another measurement position to obtain the surface sound pressure level, the operations in steps S102 to S112 described above are repeated.

[0058] Then, once the surface sound pressure levels at all pre-stored measurement positions are obtained, the measurement control device 100 calculates the incident power level from the surface sound pressure levels (step S113). That is, for example, the average value of the surface sound pressure levels at multiple measurement positions is obtained, and the power level of the sound incident on the building material 30 is calculated from this average value. This provides the incident power level for one incident angle, but it is preferable to obtain the incident power level for multiple different incident angles. Therefore, when calculating the incident power level by changing the incident angle, the operations of steps S101 to S113 described above are repeated.

[0059] The calculated incident power levels for each incident angle are stored in association with the respective incident angles and used to determine the sound transmission loss, which is the sound insulation performance of the building material 30.

[0060] As described above, according to this embodiment, when moving the microphone to the measurement position using the microphone moving device, the microphone is moved to the XY coordinates of the measurement position, the distance to the building material is measured using an ultrasonic rangefinder integrated with the microphone, and the position of the microphone in the Z direction is adjusted based on the measured distance. Therefore, the microphone can be easily moved to a constant distance from the surface of the building material, and the surface sound pressure level at multiple measurement positions can be efficiently measured. In other words, the sound pressure level on the surface of the building material can be efficiently measured.

[0061] In the above embodiment 1, an ultrasonic distance meter 220 was used to measure the distance between the tip of the microphone 210 and the building material 30, but other distance meters may be used to measure the distance. For example, if the building material 30 is not transparent, a laser distance meter may be used to measure the distance between the tip of the microphone 210 and the building material 30 by the reflection of the laser. Alternatively, a distance meter with a mechanism in which a rod-shaped probe protrudes from its tip may be used, and the probe may be extended until it contacts the building material 30, and the amount of protrusion when the probe contacts the building material 30 may be measured as the distance to the building material 30.

[0062] (Embodiment 2) In general, ultrasonic distance meters can have relatively large measurement errors. Therefore, in Embodiment 2, we will describe a case in which the ultrasonic distance meter is calibrated before measuring the surface sound pressure level.

[0063] The schematic configuration of the surface sound pressure measurement system according to Embodiment 2 is the same as that of Embodiment 1 (Figure 1), so its explanation will be omitted.

[0064] Figure 5 is a block diagram showing the configuration of the measurement control device 100 according to Embodiment 2. In Figure 5, the same reference numerals are used for the same parts as in Figure 3, and their descriptions are omitted. The measurement control device 100 shown in Figure 5 has a microphone movement control unit 156, a measurement value acquisition unit 158, and a Z-movement amount calculation unit 160 in place of the microphone movement control unit 104, measurement value acquisition unit 106, and Z-movement amount calculation unit 108 of the measurement control device shown in Figure 3, and a calibration control unit 152 and a calibration value storage unit 154 have been added.

[0065] Prior to measuring the surface sound pressure level, the calibration control unit 152 performs a calibration process to correct the measurement error of the ultrasonic distance meter 220. Specifically, the calibration control unit 152 instructs the microphone movement control unit 156 to move the tip of the microphone 210 away from the building material 30 by a predetermined distance (e.g., 1 mm) at a time, starting from a state where the tip of the microphone 210 is in contact with the surface of the building material 30. The calibration control unit 152 then acquires and stores the distance measurement value from the ultrasonic distance meter 220 each time the tip of the microphone 210 moves by the predetermined distance.

[0066] The calibration control unit 152 calculates the measurement error of the ultrasonic distance meter 220 from the distance traveled by the microphone 210 as instructed to the microphone movement control unit 156 and the distance measurement obtained from the ultrasonic distance meter 220, and determines a calibration value to correct the measurement error. That is, the calibration control unit 152 uses the distance traveled by the microphone 210 by the microphone movement device 13 as the true value, determines the error of the measurement by the ultrasonic distance meter 220, and determines a calibration value that cancels out this error. The calibration control unit 152 also performs interpolation processing on the calibration value corresponding to each measurement by the ultrasonic distance meter 220 to obtain a calibration value corresponding to all consecutive measurements. Then, the calibration control unit 152 stores the calibration value that corrects the measurement by the ultrasonic distance meter 220 in the calibration value storage unit 154.

[0067] Furthermore, when measuring the surface sound pressure level, the calibration control unit 152 reads a calibration value from the calibration value storage unit 154 that corresponds to the distance measurement obtained by the measurement value acquisition unit 158, and notifies the Z displacement calculation unit 160 of this k calibration value. In other words, the calibration control unit 152 reads a calibration value from the calibration value storage unit 154 to correct the measurement value from the ultrasonic distance meter 220 and notifies the Z displacement calculation unit 160 of this calibration value.

[0068] The calibration value storage unit 154 stores the calibration values ​​obtained by the calibration process performed by the calibration control unit 152. In other words, the calibration value storage unit 154 stores calibration values ​​for correcting measurement errors included in the measurement values ​​of the ultrasonic distance meter 220, in association with the measurement values.

[0069] Prior to measuring the surface sound pressure level, the microphone movement control unit 156 outputs a predetermined amount of movement to the microphone movement device 13, in accordance with instructions from the calibration control unit 152, to move the microphone 210 in the Z direction by a predetermined distance. That is, the microphone movement control unit 156 controls the microphone movement device 13 to move the tip of the microphone 210 away from the building material 30 by a predetermined distance (e.g., 1 mm) at a time, starting from a state where the tip of the microphone 210 is in contact with the surface of the building material 30.

[0070] Furthermore, when the measurement position of the microphone 210 is instructed during surface sound pressure level measurement, the microphone movement control unit 156 calculates the amount of movement in the X and Y directions from the current position of the microphone 210 to the instructed measurement position, and outputs the calculated amount of movement to the microphone movement device 13. Then, after the microphone 210 has moved to the XY coordinates of the measurement position by the microphone movement device 13, when the amount of movement in the Z direction is notified by the Z movement amount calculation unit 160, the microphone movement control unit 156 outputs the notified amount of movement in the Z direction to the microphone movement device 13.

[0071] Prior to measuring the surface sound pressure level, the measurement unit 158 ​​acquires a measurement of the distance to the building material 30, measured by the ultrasonic distance meter 220, each time the microphone 210 moves a predetermined distance in the Z direction. That is, for example, the measurement unit 158 ​​acquires a measurement of the distance from the ultrasonic distance meter 220 each time the tip of the microphone 210 moves a predetermined distance (e.g., 1 mm) away from the building material 30, starting from a state where the tip of the microphone 210 is in contact with the surface of the building material 30.

[0072] Furthermore, when the microphone 210 moves to the XY coordinates of the measurement position during surface sound pressure level measurement, the measurement value unit 158 ​​acquires the measurement value of the distance to the building material 30 measured by the ultrasonic distance meter 220.

[0073] When the measurement value from the ultrasonic distance meter 220 is acquired by the measurement value acquisition unit 158, the Z-movement amount calculation unit 160 corrects the measurement value using the calibration value notified by the calibration control unit 152, calculates the amount of movement in the Z direction to the measurement position based on the corrected measurement value, and notifies the microphone movement control unit 156 of the calculated amount of movement in the Z direction. In this way, the Z-movement amount calculation unit 160 can reduce the measurement error of the ultrasonic distance meter 220 and notify the amount of movement so that the distance from the tip of the microphone 210 to the building material 30 is accurately indicated.

[0074] Here, the calibration process according to Embodiment 2 will be explained with reference to the flowchart shown in Figure 6. The calibration process shown in Figure 6 is performed prior to the measurement of the surface sound pressure level, and only needs to be performed once before the surface sound pressure level is measured by the surface sound pressure measurement system.

[0075] When starting the calibration process, the sound receiving unit 200 is moved manually, and the tip of the microphone 210 is brought into contact with the surface of the building material 30. At this time, the distance between the tip of the microphone 210 and the building material 30 is 0, so distance measurement is performed by the ultrasonic distance meter 220 as needed, and the calibration control unit 152 may determine the calibration value from the measured value and the true distance of 0.

[0076] Then, the calibration control unit 152 instructs the microphone movement control unit 156 to move the tip of the microphone 210 away from the building material 30 by a predetermined distance (for example, 1 mm), and the microphone movement device 13 moves the microphone 210 away from the building material 30 by the predetermined distance (step S201). When the microphone 210 is separated from the building material 30, the ultrasonic distance meter 220 measures the distance to the building material 30, and the measurement value acquisition unit 158 ​​acquires the measurement value (step S202). The calibration control unit 152 then temporarily stores the measurement value along with the actual distance the microphone 210 has moved (step S203).

[0077] The Z-direction distance adjustment mechanism of the support arm 13b of the microphone moving device 13 has a range of motion, and the Z-direction origin of the position of the microphone 210 is set in advance. The calibration control unit 152 then determines whether the current position of the microphone 210 has reached the Z-direction origin (step S204), and if it has not yet reached the Z-direction origin (step S204No), the microphone 210 moves again a predetermined distance away from the building material 30 (step S201). Then, the measurement of distance by the ultrasonic distance meter 220 and the storage of the measured value are repeated.

[0078] On the other hand, when the current position of microphone 210 reaches the origin in the Z direction (step S204 Yes), calibration values ​​corresponding to each measurement are determined from the stored measurement values ​​and the actual distance traveled. That is, calibration values ​​that cancel out the error between the measurement value and the actual distance traveled are determined for each measurement value. Furthermore, calibration values ​​corresponding to each measurement value are interpolated (step S205), and calibration values ​​corresponding to all consecutive measurement values ​​are obtained. The obtained calibration values ​​are associated with the measurement values ​​and stored in the calibration value storage unit 154 (step S206).

[0079] In this way, by storing calibration values ​​to correct the measured values ​​of the ultrasonic distance meter 220 prior to measuring the surface sound pressure level, the measured values ​​of the ultrasonic distance meter 220 can be corrected using the calibration values ​​when measuring the surface sound pressure level, thereby obtaining an accurate distance between the tip of the microphone 210 and the building material 30.

[0080] Next, the surface sound pressure measurement method using the surface sound pressure measurement system configured as described above will be explained with reference to the sequence diagram shown in Figure 7. In Figure 7, the same reference numerals are used for the same parts as in Figure 4, and their detailed explanations are omitted.

[0081] First, once the angle of sound incidence onto the building material 30 and the measurement position of the microphone 210 are determined from the measurement conditions, the measurement control device 100 instructs the speaker moving device 11 to move the speaker 12 to the destination corresponding to the angle of incidence (step S101). The measurement control device 100 also instructs the microphone moving device 13 to move the microphone 210 to the XY coordinates of the determined measurement position (step S102).

[0082] When the microphone 210 moves to the XY coordinates of the measurement position, the measurement control device 100 instructs the ultrasonic distance meter 220 to measure the distance to the building material 30 (step S103). Upon receiving this instruction, the ultrasonic distance meter 220 measures the distance to the building material 30 (step S104), and the measured value is output to the measurement control device 100 (step S105).

[0083] When the measurement control device 100 acquires a distance measurement, the measurement is corrected using a calibration value corresponding to the measurement (step S301). Based on the corrected distance, the amount of movement in the Z direction required to move the microphone 210 to the measurement position is calculated (step S302), and the calculated amount of movement is output to the microphone moving device 13 (step S107). Then, the microphone 210 is moved by the microphone moving device 13 according to this amount of movement, and the distance between the tip of the microphone 210 and the building material 30 becomes the distance corresponding to the measurement position.

[0084] In this way, since the measurement value from the ultrasonic distance meter 220 is corrected using a calibration value before moving the microphone 210 to the measurement position, the microphone 210 can be accurately positioned at the measurement location, making it possible to accurately measure the surface sound pressure level of the building material 30. Furthermore, since the microphone 210 is accurately positioned at the measurement location, in this embodiment, it is possible to omit the confirmation of whether the microphone 210 is correctly positioned at the measurement location.

[0085] As a result of the operations performed so far, the speaker 12 and microphone 210 are positioned to measure the surface sound pressure level. The measurement control device 100 controls the speaker 12 and microphone 210 so that the speaker 12 emits sound and the microphone 210 receives this sound (step S111). Once the received waveform at the microphone 210 is acquired, the measurement control device 100 calculates the surface sound pressure level from the received waveform (step S112). Then, once the surface sound pressure levels at all pre-stored measurement positions have been obtained, the measurement control device 100 calculates the incident power level from the surface sound pressure level (step S113). The calculated incident power levels for each incident angle are stored in association with the respective incident angles and are used to determine the sound transmission loss, which is the sound insulation performance of the building material 30.

[0086] As described above, according to this embodiment, before measuring the surface sound pressure level, a calibration value is obtained to correct the measurement error of the ultrasonic distance meter. When measuring the surface sound pressure level, the distance to the building material is measured using an ultrasonic distance meter integrated with the microphone, the measured distance is corrected using the calibration value, and the position of the microphone in the Z direction is adjusted based on the corrected measured value. Therefore, even when using an ultrasonic distance meter with relatively low accuracy, the microphone can be accurately moved to a constant distance from the surface of the building material, and the surface sound pressure level can be efficiently measured at multiple measurement positions. In other words, the sound pressure level on the surface of the building material can be efficiently measured. [Explanation of symbols]

[0087] 10 Anechoic chamber 11. Speaker relocation device 12 speakers 13 Microphone relocation device 20 Reverberation Room 30 Building materials 100 Measurement and control device 102 Measurement instruction section 104, 156 Microphone movement control unit 106, 158 Measurement acquisition unit 108, 160 Z movement amount calculation section 110 Microphone control unit 112 Speaker movement control unit 114 Speaker Control Unit 116 Sound pressure level calculation unit 118 Incidence Power Calculation Unit 120 Injection power storage unit 152 Calibration Control Unit 154 Calibration Value Storage Unit 200 Sound receiver 210 microphones 220 Ultrasonic Distance Meter

Claims

1. A sound receiving unit formed by integrating a microphone and a rangefinder, A microphone relocation device that movably supports the sound receiving unit opposite a building material installed as the subject of sound insulation performance evaluation, It comprises a measurement control device that controls the sound receiving unit and the microphone moving device, The measurement control device is An acquisition unit that acquires a measurement of the distance from the sound receiving unit to the building material using the distance meter, A calculation unit calculates the amount of movement from the current position of the sound receiving unit to a predetermined measurement position based on the measurement values ​​obtained by the acquisition unit, A movement control unit instructs the microphone movement device to move the sound receiving unit by the amount of movement calculated by the calculation unit, A sound pressure level calculation unit calculates the surface sound pressure level of the building material from the sound waveform received by the sound receiving unit after it has been moved, A surface sound pressure measurement system having the following features.

2. The aforementioned sound receiving unit is An ultrasonic distance meter that measures the distance to the building material using ultrasound and a microphone are formed as an integrated unit. The surface sound pressure measurement system according to claim 1.

3. The acquisition unit is, After the sound receiving unit moves parallel to the surface of the building material to a position corresponding to the predetermined measurement position, the measurement value is acquired by the distance meter. The surface sound pressure measurement system according to claim 1.

4. The measurement control device is A calibration value storage unit stores a calibration value obtained from the measurement value by the distance meter and the distance the sound receiving unit moves using the microphone moving device, which compensates for the measurement error included in the measurement value by the distance meter. The system further includes a calibration control unit that corrects the measured values ​​acquired by the acquisition unit using the calibration values ​​stored in the calibration value storage unit, The calculation unit described above, Based on the measured value corrected by the calibration control unit, the amount of movement from the current position of the sound receiving unit to a predetermined measurement position is calculated. The surface sound pressure measurement system according to claim 1.

5. The system further includes a speaker moving device that movably supports a speaker that radiates sound toward the aforementioned building material, The aforementioned sound receiving unit is The sound emitted from the speaker is received by the microphone. The surface sound pressure measurement system according to claim 1.

6. A surface sound pressure measurement method performed by a surface sound pressure measurement system having a sound receiving unit formed by integrating a microphone and a rangefinder, a microphone moving device that movably supports the sound receiving unit facing a building material installed as a target for sound insulation performance evaluation, and a measurement control device that controls the sound receiving unit and the microphone moving device, The measurement control device, The distance from the sound receiving unit to the building material is measured using the distance meter, Based on the acquired measurement values, the amount of movement from the current position of the sound receiving unit to a predetermined measurement position is calculated. The microphone moving device is instructed to move the sound receiving unit by the calculated amount of movement. The surface sound pressure level of the building material is calculated from the sound waveform received by the sound receiving unit after it has been moved. A surface sound pressure measurement method that includes a processing step.

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