JP5943298B2 - Noise source search system - Google Patents

Description

  The present invention relates to a noise source search system mainly used for noise source search at a construction site.

  At construction sites, various construction machines such as bulldozers, tractor excavators, and backhoes are operating on the premises, and various generated sounds including their operating noise propagate to the surroundings. If this measure is not taken, there is a concern that the above-mentioned generated sound will propagate to the surroundings and become noise, causing unexpected health damage or living damage to neighboring residents.

  For this reason, noise related to construction work is regulated based on the Noise Regulation Law, and noises due to construction work on the site must not exceed the regulation standards at the site boundary by setting target values as appropriate. I must.

  Under such circumstances, various technological developments have been conducted in the past to monitor noise associated with construction work.To take measures such as stopping construction machines when the target value is exceeded, It is necessary to specify the position of the sound source, and in order to do so, it is important to grasp the direction of arrival of the sound propagating from the sound source.

  Here, the sound propagating through the medium has its sound pressure and particle velocity as physical quantities, and their product corresponds to energy flowing in a unit area per unit time along the propagation direction. That is, if the sound intensity can be measured, since it is a vector quantity, it is possible to grasp the sound field including the sound arrival angle.

  Sound intensity measurement has been tried for a long time, but since it is difficult to measure the particle velocity accurately, it is separated along a predetermined direction using the fact that the inertial force and elastic force are equal in the equation of motion of sound waves. The so-called two-microphone method in which the particle velocity is obtained from the difference between the sound pressures at two points, and the sound intensity is approximately obtained by multiplying the particle velocity by the sound pressure (average value at two points) and taking the time average. (Pp method) is a typical calculation method for obtaining sound intensity (Patent Documents 1 to 3, Non-Patent Document 1).

  In addition, in the pp method, since the distance between the microphones is required for the calculation, it is required to accurately install the microphones, and the distance between the microphones becomes large in the low frequency range, and the apparatus is Due to the increase in size, application to construction sites was naturally limited, but a sound intensity calculation method called the cc method using directional microphones has been researched and developed. For example, since it is not necessary to adjust the separation distance of the microphone in accordance with the target frequency, it is possible to expand the application by downsizing, and the spread thereof is expected greatly including construction work sites (Patent Documents 4 to 6, non-patent documents). Patent Documents 2 and 3).

JP 2003-111183 A JP 2011-13030 A JP 2011-27687 A International Publication No. 2009-153999 Pamphlet International Publication No. 2006-054599 Pamphlet JP 2008-249702 A

"Measurement of environmental noise and architectural acoustics" (Edited by the Acoustical Society of Japan, published by Corona, published on March 30, 2004, first edition) "Sound source search using sensitivity differences among multiple directional microphones" (Proceedings of the Acoustical Society of Japan, March 2006, pages 781 to 782) "Intensity measurement method based on Fourier series expansion of direction information of sound field" (acoustics of the Acoustical Society of Japan, September 2006, pages 721-722)

  Here, in order to monitor noise caused by construction work, it is necessary to distinguish whether the noise is caused by sound generated within the construction site or whether it is caused by sound generated outside the site that is not related to the construction work. There is.

  However, while distinguishing from the sound generated from outside the site, it is appropriate and prompt to determine which of the many construction machines scattered within the site or traveling vertically and horizontally within the site is the source of noise. No identifiable technology has been developed yet.

  In addition, noise monitoring based on the Noise Regulation Law requires the use of a legal measuring instrument defined by the Measurement Law, that is, a sound level meter that has passed the verification, so in the cc method using a microphone with directivity, There was also a problem that it was difficult to monitor noise based on the regulation law.

  On the other hand, the noise level measured by the sound level meter reflects various generated sounds inside and outside the site, so if the measured noise level exceeds the target value, the cause is on the site. There was a problem that it was impossible to distinguish whether it was outside, and as a result, a long-term on-site monitoring system was required by workers.

  The present invention has been made in consideration of the above-mentioned circumstances, and any of a large number of construction machines that are scattered in the site of the construction site or run vertically and horizontally in the site becomes a noise source. It is an object of the present invention to provide a noise source search system that can quickly identify whether or not a user is present.

  In addition, the present invention enables noise monitoring based on the noise regulation law while enabling miniaturization, and appropriately determines whether or not the cause of noise is in the premises when the noise level exceeds the target value. An object of the present invention is to provide a noise source search system that can perform such operations.

  In order to achieve the above object, a noise source search system according to the present invention, as described in claim 1, is a sound for measuring the sound pressure of a generated sound at a measurement point set near the boundary of a site that is a noise monitoring area. A pressure measurement unit, an arrival angle calculation unit that calculates an arrival angle of the generated sound using the sound pressure value measured by the sound pressure measurement unit, and an arrival angle obtained from the arrival angle calculation unit A direction display image corresponding to the synthesis target arrival angle is a plane layout image in which the sound source layout status in the site is shown as a plane layout diagram, and is superimposed on the corresponding position of the measurement point on the plane layout image A composite image creating unit for creating a composite image, and display means for displaying the composite image.

  In the noise source search system according to the present invention, the sound pressure measuring means is configured so that the sound pressure values of the generated sound are respectively measured at the two measurement points with the measurement points being two different measurement points. In addition, the arrival angle calculation unit is configured such that the arrival angles at the two measurement points are calculated as two synthesis target arrival angles from the sound pressure values measured at the two measurement points, and the composite image creation The direction display image corresponding to each of the two synthesis target arrival angles is the planar layout image and is superimposed on the corresponding position of the two measurement points on the planar layout image. is there.

  Further, in the noise source search system according to the present invention, the sound pressure measuring means is arranged such that two microphones having directivity are arranged so that the maximum sensitivity directions are opposite to each other, and the microphone pairs are parallel to each other. Are arranged so as to be along a plurality of non-axial axes and sandwich their origins.

  In addition, the noise source search system according to the present invention includes a noise measuring unit that is arranged near the measurement point and measures the sound pressure of the generated sound as a noise level, and outputs the noise level to the display unit. It is a thing.

Further, the noise source search system according to the present invention is a noise measuring means arranged near the measurement point for measuring the sound pressure of the generated sound as a noise level,
An auditory correction circuit is provided for filtering the sound pressure value measured by each microphone with a frequency weighting characteristic substantially the same as the frequency weighting characteristic incorporated in the noise measuring means, and the processing result is output to the arrival angle calculation unit. A filter section to perform,
An arrival frequency counting unit that counts the number of arrivals of the generated sound in a predetermined time width for each arrival angle using the arrival angle obtained by the arrival angle calculation unit;
Dividing the number of arrivals for each arrival angle obtained by the arrival frequency counting unit by the sum of all directions to calculate the influence rate for each arrival angle, and overlooking the site using the influence rate and the noise level A noise index creating unit configured to calculate a noise index caused by a generated sound within an angular range as a site noise level and to output the site noise level together with the noise level to the display means It is.

  The noise source search system according to the present invention includes a noise waveform processing unit that creates a time history waveform of the noise level or the noise level in the site in addition to the noise level and outputs the time history waveform to the display means. Is.

  Further, the noise source search system according to the present invention is a sound pressure related system that stores the sound pressure value measured by the sound pressure measuring means or the arrival angle calculated by the arrival angle calculation unit using the sound pressure value. A data accumulating unit and a time designating unit for designating a reproduction time, and reading out from the sound pressure related data accumulating unit a sound pressure value at a sound pressure measurement time that coincides with the designated time input via the time designating unit; The arrival angle calculated by the arrival angle calculation unit using the sound pressure value is set as the synthesis target arrival angle, or the arrival angle at the sound pressure measurement time that coincides with the specified time is the sound pressure related data storage unit. And is used as the synthesis target arrival angle, and the synthesis target arrival angle is output to the composite image creation unit.

  In addition, the noise source search system according to the present invention creates a time history waveform of the noise level or the noise level in the site in addition to the noise level, and the time history corresponding to the specified time input via the time specifying means. There is provided a noise waveform processing section for displaying a reproduction position marker as an image at a position on the waveform to produce a time history waveform image and outputting the time history waveform image to the display means.

  Further, in the noise source search system according to the present invention, the arrival angle calculation unit is configured such that the magnitude of energy of the generated sound is calculated as an energy value for each generated sound, and the arrival frequency counting unit Is configured such that the number of arrivals of the generated sound is weighted by the energy value of the generated sound.

  Further, the noise source search system according to the present invention is provided with a heavy equipment selection circuit for filtering the measurement value by each microphone with a frequency characteristic according to the type of construction machine in the site, and the site. The internal noise level is the noise level in the heavy equipment separate site.

  Further, the noise source search system according to the present invention compares the noise level in the site or the noise level in the site according to heavy machinery with a predetermined target value, and compares the noise level in the site or the noise level in the site according to heavy machinery. Is provided with an alarm generation unit that generates alarm data when the value exceeds the target value, and an alarm output unit that outputs the alarm data generated by the alarm generation unit.

  In the noise source search system according to the present invention, the alarm output unit is provided in a construction machine that operates in the site.

  In the noise source search system according to the present invention, the arrival angle calculation unit calculates the arrival angle of the generated sound using the measured sound pressure value of the generated sound, and synthesizes the arrival angle obtained from the arrival angle calculation unit. The target arrival angle and the direction display image corresponding to the synthesis target arrival angle is a planar layout image in which the sound source layout status in the site is shown as a planar layout diagram, and the correspondence of the measurement points on the planar layout image A composite image is created by being superimposed on the position, and this is displayed on a display means such as a monitor.

  In this way, it is possible to confirm where the generated sound is coming from on the plane layout diagram showing the sound source arrangement status in the site, and thus the position of the noise source can be specified appropriately and quickly. be able to.

  In order to superimpose the direction display image corresponding to the synthesis target arrival angle on the planar arrangement image, it is necessary to match the reference direction of the arrival angle with the reference direction of the planar arrangement diagram. Since it can be uniquely determined as a fixed value from the installation direction or installation posture of the means, for example, it may be appropriately set as an initial condition. The reference orientation of the plan layout drawing is determined at the time of drawing creation, and therefore the same processing may be performed.

  The direction display image can be composed of an arbitrary figure as long as the generated sound can be grasped from any angle on the plane layout diagram or the plane layout image obtained by imaging it. For example, a line figure superimposed on the planar arrangement image so as to pass through a corresponding position of the measurement point on the planar arrangement image, or an arrow figure superimposed on the planar arrangement image so that the corresponding position of the measurement point is the starting point. In the latter case, the sound pressure of the generated sound can be expressed by the length of the arrow. In addition, when displaying a direction display image, it is possible to apply an arbitrary effect. For example, in a real time mode or a playback mode, which will be described later, by fading out, a temporal change in arrival angle can be visually observed. It becomes possible to capture.

  Various construction machines such as bulldozers, tractor excavators, backhoes, cranes, and dump trucks can transmit noise to their surroundings due to their various operating sounds, including their own operating and operating sounds. The plane layout of the invention shows the location where the generated sound is generated, that is, the position of the sound source and the range of the sound source, and the position, shape, operating range, boom turning range, etc. of various construction machines are shown. included.

  The search for the noise source can be performed by specifying a construction machine on the plane layout image that exists along or on the extension of the direction display image. It is not always easy to identify each other when there are a plurality of construction machines along or on the display image.

  In such a case, the sound pressure measuring means is configured so that the sound pressure value of the generated sound is measured at the two measurement points, and the two measurement points are used as the two measurement points. The arrival angle calculation unit is configured so that the arrival angles at the two measurement points are respectively calculated as two synthesis target arrival angles from the measured sound pressure values, and the composite image creation unit is configured as the two synthesis targets. If the direction display image corresponding to each arrival angle is the above-described plane arrangement image and is superimposed on the corresponding positions of the two measurement points on the plane arrangement image, the construction that is a noise source A construction machine can be identified as a construction machine on a plane layout image that exists at the intersection of two directional display images or at the intersection of their extension lines. Because, it is possible to search the noise source more reliably.

  The sound pressure measuring means and the arrival angle calculation unit can have any configuration as long as the sound pressure value can be measured and the arrival angle of the generated sound can be calculated using the sound pressure value. For example, in the case of the pp method, the arrival angle can be calculated using a microphone pair including two omnidirectional microphones (Patent Documents 1 to 3, Non-Patent Document 1).

  On the other hand, in the case of the cc method, the difference value of the sound pressure measured by the microphone pair composed of two microphones having directivity is collated with the microphone sensitivity difference for each angle of arrival stored in the storage means in advance. The angle of arrival is estimated (Patent Documents 4 and 5, Non-Patent Document 2), or the sum value and difference value of the sound pressures measured by the microphone pair are multiplied or the difference value of the square sound pressure is calculated. By dividing by the acoustic impedance ρc (ρ; air density, c; sound velocity), the sound intensity component along the arrangement axis of the microphone pair is calculated, and another microphone pair is used along different axial directions. It is possible to calculate the sound intensity component in the same manner and to estimate the angle of arrival from the vector component of the sound intensity (Patent Documents 4 and 6). Permissible literature 3).

  According to these cc methods, since the separation distance of the microphone can be kept constant regardless of the target frequency, the sound pressure measuring means can be made smaller than the pp method, and Easy to apply.

  When calculating the angle of arrival based on the cc method, the sound pressure measuring means arranges two microphones having directivity so that the maximum sensitivity directions are opposite to each other, and forms a microphone pair. It is mainly assumed that each of the components is arranged along three axes orthogonal to each other. However, if it is sufficient to approximately grasp the arrival angle of the generated sound on a two-dimensional plane, for example, a horizontal plane, two directions in the horizontal plane are sufficient. A pair of microphones may be installed along two axes extending in the direction. On the other hand, in estimating the angle of arrival from the vector component of the sound intensity, the plurality of axes do not necessarily have to be orthogonal, for example, along the four axes extending from the center of the regular tetrahedron toward the four vertices, respectively. By installing each microphone pair, it is possible to grasp the angle of arrival in a three-dimensional space.

  In other words, the sound pressure measuring means for calculating the angle of arrival based on the cc method may be a configuration in which microphone pairs are respectively arranged along a plurality of axes that are not parallel to each other and sandwich their origins. .

  In the cc method, the microphone has directivity such as a cardioid, a super cardioid, and a hyper cardioid.

  The search for the noise source may be performed regardless of the noise level, but includes noise measurement means arranged near the measurement point and measuring the sound pressure of the generated sound as the noise level, and the noise level is determined. If configured to output to the display means, while monitoring the noise level in accordance with the regulations on noise regulations such as the Noise Regulation Law, when the noise level exceeds a regulation value or a target value based thereon, The above-described noise source search can be performed, and the noise source search can be performed more efficiently.

  In the present invention, it is sufficient to perform sound pressure measurement within an angular range overlooking the site, and it is not always necessary to perform the sound pressure measurement in all directions, but there is a separate noise measuring means for measuring the sound pressure of the generated sound as a noise level. In addition, using the calculated arrival angle, count the number of arrivals of the generated sound in a predetermined time width for each arrival angle, and divide the arrival number for each arrival angle by the sum of all directions to influence the arrival angle. And calculating the noise index due to the sound generated within the angular range over which the site is overlooked as the site noise level using the influence rate and the noise level, and outputting them to the display means. For example, it is possible to rationally search for a noise source while performing noise monitoring based on a law concerning noise regulation.

  That is, in such a configuration, separately from the sound pressure measurement by each microphone, the sound pressure of the generated sound is measured as the noise level by the noise measuring means. The noise measuring means shall be composed of a certified sound level meter.

  Next, the measured value by each microphone is filtered by the A characteristic if the frequency weight characteristic substantially the same as the frequency weight characteristic built in the noise measuring means, for example, the frequency weight characteristic built in the noise measuring means is an A characteristic. After that, the result is output to the arrival angle calculation unit, and then the arrival angle of the generated sound is calculated according to the procedure of the cc method described above.

  In the prior art, the noise level means a sound pressure level filtered by the A characteristic among the frequency weighting characteristics. However, in the present invention, not only the A characteristic but also other frequency weights for auditory correction. The characteristics are included and the noise level in the premises is the same.

  In calculating the arrival angle of the generated sound by the arrival angle calculation unit, for example, 0.1 second is set as the time width Δt, and the generated sound is sampled at intervals of 0.001 seconds in each time width Δt, and each arrival angle is calculated. May be calculated by the estimation method described above.

  Next, the arrival frequency counting unit counts the number of arrivals of the generated sound in the time width Δt for each arrival angle using the arrival angle data obtained by the arrival angle calculation unit.

  When counting for each angle of arrival, if it is a two-dimensional plane, 360 ° of the entire circumference is divided into 10 °, for example, 0 ° to 10 °, 10 ° to 20 °, and so on. If the number of generated sound arrivals is counted for each width and grasped in a three-dimensional space, for example, the number of generated sound arrivals may be similarly counted for another two-dimensional plane orthogonal to the above-described two-dimensional plane.

Next, when the number of arrivals for each arrival angle θ obtained by the arrival frequency counting unit is N (θ) and the sum related to θ, that is, the sum of all directions is ΣN (θ),
C (θ) = N (θ) / ΣN (θ) (2)
Thus, C (θ) is calculated by the noise index creation unit. Where C (θ) is
0 ≦ C (θ) ≦ 1
It is.

  C (θ) is obtained by dividing the number of arrivals N (θ) of the generated sound for each arrival angle θ by the sum ΣN (θ), and for each arrival angle θ with respect to the arrival frequency of the generated sound from all directions. In the following, C (θ) is referred to as an influence rate. Note that θ is assumed to be handled as a value having a certain width such as 0 ° to 10 °, 10 ° to 20 °, etc. as described above for convenience of calculation processing. In the case where the angle of arrival is constant and the arrival angle is constant, it may be handled as a value having substantially no width.

  The influence rate C (θ) is defined as the ratio of the arrival frequency for each angle of arrival θ with respect to the arrival frequency of the sound generated from all directions as described above. Therefore, the noise level is calculated using C (θ). By allocating, it is possible to evaluate a noise index caused by sound generated from a predetermined angle range.

For example, if C _T is the sum of C (θ) in the angle range θ _{1 to} θ ₂ , C (θ) (θ = θ _{1 to} θ ₂ ), the energy of the generated sound coming from all directions is expressed as E for convenience. When this is determined and multiplied by C _T , the multiplication result can be considered as the energy E _{T of the} generated sound coming from the predetermined angle range θ _{1 to} θ ₂ . That is,
E _T = E · C _T (3)
Here, when the reference value of the energy of the generated sound is E ₀ ,
E _T / E ₀ = E / E ₀ · C _T
So, taking the common logarithm of both sides and multiplying by 10,
10 · log (E _T / E ₀ ) = 10 · log (E / E ₀ ) + 10 · log C _T (4)
It becomes.

On the other hand, the noise level is the square of the sound pressure or the sound energy expressed in decibels. The first term on the right side of the equation (4) corresponds to this noise level. if you put the L _T,
L _T = L + 10 · logC _T (1)
It becomes.

Here, since the second term on the right side of the equation (1) takes zero or a negative value, L _T is a value smaller than the noise level L, and is noise caused by sound generated from a predetermined angle range. It can be considered an indicator.

The noise level in the prior art is a noise index based on the premise that the generated sound is measured in all directions using an omnidirectional microphone, and the noise cannot be grasped according to the difference in the arrival angle. On the other hand, in the above-described configuration, the ratio of the arrival frequency for each angle of arrival θ with respect to the arrival frequency of the sound generated from all directions is calculated, and this is defined as the influence rate C (θ), and then the influence rate or the predetermined frequency is determined. allocating the at angular range theta ₁ through? ₂ by performing the calculation of example (1) using the sum C _T of C (theta), the noise level L is omnidirectional in noise indices L _T for each angular range be able to.

Since the noise indices due to sound generated from the predetermined angle range is not present in the prior art, hereinafter, grounds predetermined angular range, the noise indices L _T in a case where an angle range that can overlook the grounds It is called the internal noise level and is distinguished from the noise level L that is omnidirectional.

  The angle range over which the site can be seen is 90 ° if the site is rectangular and the vicinity of the corner is the measurement point, and 180 ° if the vicinity of the long side or short side edge is the measurement point. And can be set respectively.

The on-site noise level L _T For example, in a case where the site is noise monitoring area is overlooked at 0 ° to 90 ° angle range as viewed from the measurement point, the entire periphery 360゜Wo 0 ° to 90 ° the other When the number of arrivals of the generated sound arriving during Δt in the angle range of 0 ° to 90 ° is 50 and the number of arrivals in the other angle ranges is 50, the number of arrivals for each angle of arrival is divided. total, that is, the incoming number is 100 from all directions, site noise level at 0 ° to 90 ° angle range L _T is
L _T = L + 10 · log (50/100) ≈L−3
Next, on-site noise level L _T, smaller by about 3dB than the noise level L. That is, in the above example, rather than performing noise monitored using the noise level L, it can be seen that it is sufficient to noise monitored using 3dB lower-site noise level L _T than該騒sound level.

  In this way, if the noise level is calculated by the noise index creation unit using the influence rate and the noise level and these numerical values are output to the display means, the noise level measured by the sound level meter will arrive. Since the noise level for each angle is assigned according to the influence rate for each angle, the noise level for each angle corresponding to the angle range, that is, the site is set by appropriately setting the angle range corresponding to the noise monitoring area. It is sufficient to search for the noise source only when the internal noise level exceeds the target value, and the noise level is set to the target value by the sound generated from other than the noise monitoring area, for example, the sound generated from a car traveling on the surrounding road. It is not necessary to search for a noise source even when the search for the noise source is not necessary.

  Even when a search for a noise source is required, it is possible to immediately confirm where the generated sound is coming from on the plane layout image as described above, so that the position of the noise source can be appropriately and quickly determined. It becomes possible to specify.

  The above configuration in which the noise index creation unit calculates the in-site noise level using the influence rate and the noise level is measured as a noise level in a state where the generated sound to be monitored is synthesized with the generated sound not to be monitored. Therefore, it can be applied to all situations where it is not possible to take appropriate noise countermeasures for monitored objects. For example, metal processing machines, compressors, looms, and printing machines that are subject to regulation by the Noise Regulation Law. It can be applied to production facilities where machines are installed and various construction sites.

  The sound pressure value measured by the sound pressure measuring means or the arrival angle calculated from the sound pressure value can be monitored in real time without storing the data, but is measured by the sound pressure measuring means. The sound pressure value or the angle of arrival calculated from the sound pressure value is stored in the sound pressure related data storage means, and the sound that coincides with the specified desired playback start time during or after the sound pressure measurement The sound pressure value at the time of pressure measurement is read from the sound pressure related data storage means, the arrival angle is calculated from the sound pressure value by the arrival angle calculation unit, and this is used as the synthesis target arrival angle, and the synthesis target arrival angle is created. If it is output to the section, it is possible to check and examine noise countermeasures using past synthesized images while monitoring noise in real time or at another opportunity, for example, saving data throughout the day Is While looking at the composite image, or to grasp the situation of the sound generated in the previous day, it is possible to or examined the effect confirmation or new measures of noise control.

  The time designation means may be configured to directly input the reproduction time as a numerical value, but a graphic interface is known that arbitrarily changes or designates the reproduction time by sliding a button indicating the reproduction position with a pointing device, This can be configured to be displayed on the display means.

  The data to be accumulated in the sound pressure related data accumulating means may be the arrival angle calculated by the arrival angle calculation unit from the sound pressure value instead of the above sound pressure value, and in that case The arrival angle is read from the sound pressure related data storage means, and this can be used as the synthesis target arrival angle as it is.

  Even if the noise level and site noise level are displayed as numerical values on the display means, it is possible to perform reasonable noise monitoring as described above. If a noise waveform processing unit that generates a level time history waveform and outputs the time history waveform to the display means is provided, the current value is confirmed while comparing the noise level and the noise level in the site with the past value. Therefore, more appropriate noise monitoring becomes possible.

  Here, in the case where the sound pressure value or the arrival angle calculated from the sound pressure value is stored in the sound pressure related data storage means, the time history waveform that matches the designated time input via the time designation means The noise waveform processing unit is configured such that the reproduction position marker is displayed as an image at the upper position to form a time history waveform image, and the time history waveform image is output to the display means.

  In this way, the noise level at the same time as the composite image and the size of the noise level in the premises are indicated by the reproduction position marker as the position of the time history waveform, so noise countermeasures using past composite images can be performed. It becomes possible to conduct a closer examination.

  As long as the arrival frequency of the generated sound is counted for each arrival angle, the configuration of the arrival frequency counting unit is arbitrary. For example, each time the generated sound arrives, the frequency may be simply counted. Is configured so that the magnitude of the energy of the generated sound is calculated as an energy value for each of the generated sounds, and the arrival frequency counting unit is configured so that the number of arrivals of the generated sounds is If it is configured to be weighted by the energy value of the generated sound, the influence rate and noise level in the site are also calculated in a form weighted by the energy value of the generated sound, so the impact on noise is more dominant. It becomes possible to perform noise monitoring mainly on the generated sound.

  Here, if the filter unit is provided with a heavy equipment selection circuit that filters the measurement values by the microphones with frequency characteristics according to the type of construction machine on the site, the calculated noise level in the site is calculated. It is possible to easily identify which construction machine is caused by. Hereinafter, the site noise level corresponding to a specific construction machine is referred to as the heavy machinery specific site noise level.

  The noise level in each heavy equipment site is a new noise index filtered by the frequency weighting characteristic for selecting heavy equipment in addition to the frequency weighting characteristic for auditory correction, and is conventionally corrected by the A characteristic. The noise level is different.

  The heavy equipment sorting circuit is configured to correspond to a plurality of construction machines, and is configured to be switchable to which construction machine is to be filtered, and further adapted to construction machines. It is desirable that the frequency filtering should be switchable.

  It is arbitrary how the noise level in the site calculated by the above-mentioned procedure or the noise level in the site classified by heavy machinery is used for noise monitoring. After considering appropriate noise countermeasures based on this, the noise countermeasures may be reflected in the construction work on the next day. An alarm creation unit that creates alarm data when the noise level in the site or the noise level in each heavy machinery exceeds the target value, and the alarm data created by the alarm creation unit is output. If an alarm output unit is provided, noise countermeasures can be taken in real time.

  Here, the configuration and location of the alarm output unit is arbitrary. For example, the screen is displayed on a computer installed in the construction office. Although it is possible to contact the construction machine operator, it is possible to further improve the immediateness of noise countermeasures if the alarm output unit is installed on the construction machine that operates on the premises. It becomes. In this case, the alarm output unit can be configured using, for example, a portable information terminal installed in the driver's seat.

It is a figure of the noise source search system 1 which concerns on this embodiment, (a) is a whole block diagram, (b) is site layout drawing. The block diagram of cc microphone 12. FIG. The detailed block diagram of the noise source search system 1 which concerns on this embodiment. It is explanatory drawing of the noise source search system 1 which concerns on this embodiment, (a) is a figure which showed a mode that the generated sound each arrived from the site 2 and the general road 4, (b) is an acoustic intensity and its component. The figure shown, (c) And (d) is the figure which showed the relationship between an acoustic intensity and an arrival angle. The graph which showed a mode that the number of arrivals of generated sound was counted for every angle of arrival. Diagram showing a display status of the monitor 26 at time t _1. Diagram showing a display status of the monitor 26 at time t _2. The block diagram of the noise source search system which concerns on a modification. The block diagram of the noise source search system which concerns on a modification. The block diagram of the noise source search system which concerns on a modification. It is a figure of the noise source search system 1 'which concerns on 2nd Embodiment, (a) is a whole block diagram, (b) is site layout drawing. The detailed block diagram of the noise source search system 1 'which concerns on this embodiment. Diagram showing a display status of the monitor 26 at time t _1. Diagram showing a display status of the monitor 26 at time t _2.

  Embodiments of a noise source search system according to the present invention will be described below with reference to the accompanying drawings.

[First Embodiment]
FIG. 1 is an overall block diagram and a site layout diagram showing a noise source search system according to the first embodiment. As can be seen from the figure, the noise source search system 1 according to the present embodiment is applied to noise monitoring of a construction machine 3 operating in a site 2 that is a noise monitoring area, and the boundary of the site 2 A cc microphone 12 as a sound pressure measuring means and a noise as a noise measuring means provided in a handset 11 located in the vicinity and between the site and the general road 4 as a measuring point. The total 13 and the arithmetic processing part 22 provided in the main | base station 21 arrange | positioned in the construction office 6 erected in the site 2 are provided.

  As shown in FIG. 2, the cc microphone 12 includes six microphones 12a to 12f having directivity, and among them, the microphones 12a and 12b, the microphones 12c and 12d, and the microphones 12e and 12f are respectively provided. The microphones are arranged so that the maximum sensitivity directions are opposite to each other, i.e., 0 ° and 180 °, to form three microphone pairs, and each microphone pair is divided into three axes orthogonal to each other, that is, x, y, z. Each of the microphones 12a to 12f measures the sound pressure of the generated sound propagated to the slave unit 11 along the axis and sandwiching the origins thereof. The microphones 12a to 12f can be configured by microphones each having cardioid directional characteristics.

  The sound level meter 13 measures the sound pressure of the generated sound as a noise level, and may be appropriately selected from commercially available sound level meters that have passed the test. It is assumed that the sound level meter 13 has a built-in filter circuit having a frequency weighting characteristic that is widely used for measuring environmental noise.

  The cc microphone 12 has an amplifier 14 that amplifies the measured sound pressure value and an A / D converter 15 that converts it into digital data. The sound level meter 13 converts the measured noise level into digital data. A / D converters 16 are connected to each other, and a transmitter 17 is connected to the output side thereof. The A / D converters 16 are installed inside a casing (not shown) together with the cc microphone 12 and the sound level meter 13. It is. It is desirable that such a housing has a configuration that is portable and takes weather resistance into consideration.

  On the other hand, the base unit 21 includes a reception unit 23 that receives transmission data wirelessly transmitted from the transmission unit 17 of the slave unit 11 and a personal computer 24, and the arithmetic processing unit 22 described above is a motherboard of the personal computer 24. , CPU, memory, built-in hard disk, and software operating on the hardware.

  The personal computer 24 has external hard disks 27 and 29 for reading out data necessary for the arithmetic processing unit 22 or storing the results of arithmetic processing, and a monitor 26 as a display means for displaying the arithmetic processing results. And a mouse 28 which is a pointing device.

  As shown in FIG. 3, the arithmetic processing unit 22 filters the sound pressure measurement value received by the cc microphone 12 received via the receiving unit 23 with the same A characteristic as the frequency weighting characteristic built in the sound level meter 13. The hard disk 27 includes an arrival angle calculation unit 44 that includes a filter unit 41 provided with an auditory sensation correction circuit and an arrival angle calculation unit 44 that calculates an arrival angle of generated sound using output data from the filter unit. It functions as a sound pressure related data accumulating means for storing the angle of arrival calculated in (1).

  The arithmetic processing unit 22 further reads out from the hard disk 27 the arrival angle of the sound pressure measurement time that coincides with the designated time input via the time designation unit 52 as the time designation means, as the synthesis target arrival angle, and the synthesis target arrival angle. Is provided with a composite image creation unit 54 for creating a composite image using the.

  The composite image creation unit 54 creates a composite image by superimposing a direction display image corresponding to the composition target arrival angle on the planar arrangement image, and outputs the composite image to the monitor 26.

  The plane layout image is an image of the plane layout showing the state of the sound source in the site 2, and the position, shape, and operating range of various construction machines such as bulldozers, tractor excavators, backhoes, cranes, and dump trucks. In addition, the turning range of the boom is shown. Such a planar arrangement image is created separately and stored in a hard disk (not shown) so that it can be read from the composite image creation unit 54 as needed.

  The direction display image is configured by an arrow graphic superimposed on the planar arrangement image so that the position on the planar arrangement image corresponding to the installation location of the slave unit 11, that is, the measurement point, is the starting point.

  The time designation unit 52 includes a graphic interface displayed on the monitor 26 and a mouse 28 that is a pointing device that slides a button indicating the reproduction position displayed on the graphic interface. Can be changed or specified.

  On the other hand, the arithmetic processing unit 22 uses the arrival angle data obtained by the arrival angle calculation unit 44 to count the arrival frequency of the generated sound in the time width Δt for each arrival angle, and the arrival frequency count. A noise index creating unit 46 that creates a noise index using the number of arrivals N (θ) for each angle of arrival obtained by the unit and the noise level L transmitted by the sound level meter 13 transmitted through the receiving unit 23. .

Here, the noise index creation unit 46 calculates the influence rate C (θ) for each arrival angle by dividing the number of arrivals N (θ) for each arrival angle by the sum over all directions, and the influence for each arrival angle. The noise level L is assigned to the noise level by angle using the rate C (θ). In FIG. 1 (b), if the coordinate system has the right direction as 0 ° and the counterclockwise direction as the positive direction, The noise level for each angle is calculated with each angle range of 0 ° to 180 ° and 180 ° to 360 °. Here, each angle noise level was 0 ° to 180゜Wo angular range, there is corresponding to the angular range overlooking the site 2, a particular site noise level L _T.

The arithmetic processing unit 22 further serves to create a time history waveform of the noise level L and grounds the noise level L _T, playback position on the time history waveform that matches the specified time inputted through the time specifying section 52 A noise waveform processing unit 55 is provided for displaying a position history image as a time history waveform image and outputting the time history waveform image to the monitor 26.

  In order to monitor the noise caused by the construction machine 3 operating in the site 2 using the noise source search system 1 according to the present embodiment, the sound level of the generated sound is measured as the noise level by the sound level meter 13. The sound pressure of the generated sound is measured by the cc microphone 12 and data is transferred to the parent device 21. In addition, the subunit | mobile_unit 11 shall be installed so that the x-axis of the cc microphone 12 may face the right direction of the figure, as shown to Fig.4 (a).

  As shown in FIG. 4 (a), the generated sound is broadly divided into those caused by the construction machine 3 in the site 2 and those caused by the vehicle 5 traveling on the general road 4. , They are measured as noise levels in all directions in the synthesized state.

  Next, the sound pressure value measured by each of the microphones 12a to 12f is converted into a frequency domain by an FFT (not shown), and then filtered by an auditory correction circuit of the filter unit 41, and time is taken by an inverse FFT (not shown). After returning to the region, the arrival angle of the generated sound is calculated by the arrival angle calculation unit 44.

As shown in FIG. 4 (b), the arrival angle calculation unit 44 calculates the added value and the difference value from the sound pressures p ₁ and p ₂ measured by the microphone pair including the microphones 12a and 12b. formula,
(p ₁ + p ₂ ) ・ (p ₁ −p ₂ ) (3)
Or multiply them by the squared sound pressure difference value,
(p ₁ ² -p ₂ ² ) (4)
And then:
(p ₁ + p ₂ ) · (p ₁ −p ₂ ) / ρc (5)
Or
(p ₁ ² −p ₂ ² ) / ρc (6)
As shown by, by dividing by acoustic impedance ρc (ρ; air density, c; sound velocity), an acoustic intensity component I _x along the arrangement axis of the microphone pair, that is, the x axis is calculated.

Similarly, the sound intensity component I _y along the y-axis is calculated using the sound pressure measured by the microphone pair composed of the microphones 12c and 12d, and the sound pressure measured by the microphone pair composed of the microphones 12e and 12f. Is used to calculate the acoustic intensity component I _z along the z-axis.

Next, using the components I _x , I _y , and I _z of the sound intensity, the arrival angle θ is converted into the angle components θ _xy and x− on the _xy plane as shown in FIGS. Calculated as the angle component θ _xz in the z plane. Note that the angle component θ _{yz in the yz} plane may be used.

  In calculating the arrival angle θ of the generated sound, for example, 0.1 seconds is set as the time width Δt, and the generated sound is sampled at intervals of 0.001 seconds in each time width Δt, and the respective arrival angles θ are described above. Calculate by procedure.

  The arrival angle calculated in this way by the angle-of-arrival calculation unit 44 is stored in the hard disk 27, which is a sound pressure-related data storage unit, together with the sound pressure measurement time of the sound pressure value that is the calculation basis.

  Next, the arrival frequency counting unit 45 counts the number of sound arrivals in the time width Δt described above for each arrival angle using the arrival angle data obtained by the arrival angle calculation unit 44.

  When counting for each angle of arrival, as shown in FIG. 5, the entire circumference is 360 ° (in the figure, for convenience, the left angle range is −180 ° to 0 °), for example, 0 ° to 10 °, It is divided into 10 ° increments of 10 ° to 20 ° (horizontal axis), and the number of generated sounds N (θ) is counted for each angular range (vertical axis).

  Note that the counting for each angle of arrival will be described assuming that the sound field is grasped on a two-dimensional plane for convenience of explanation, but when counting for each angle of arrival in a three-dimensional space, the angle of arrival is considered as a solid angle. Can be processed in the same way.

Next, the number of arrivals for each arrival angle obtained by the arrival frequency counting unit 45 is divided by the sum of all directions, and an influence rate for each arrival angle is calculated by the noise index creation unit 46. That is, if the number of arrivals for each arrival angle is N (θ), the influence rate C (θ) for each arrival angle is
C (θ) = N (θ) / ΣN (θ) (2)
ΣN (θ): Sum of N (θ) with respect to angle of arrival θ
It can be expressed as.

Next, the calculated influence rate C (θ) is summed in an angle range of 0 ° to 180 ° to obtain C _I. Here, C _I corresponds to the ratio of the area on the right side to the entire area in FIG.

Next, C _I is expressed by the following equation:
L _T = L + 10 · logC _T (1)
Substituted into the C _T, 0 ° to 180゜Wo angle range and angular-specific noise level, namely to calculate the on-site noise level L _T.

As a specific example, the C _I is assumed to be 0.7, the on-site noise level L _T from equation (1),
L _T = L + 10 · log (0.7)
= L-1.6
Becomes 1.6 dB lower than the noise level L.

Incidentally, if necessary, and C _O by summing the fraction affected C (theta) at 180 ° to 360 ° angular range, and assigns the C _T of C _O a (1) in the same manner as described above , A noise level for each angle with an angle range of 180 ° to 360 °, that is, an off-site noise level L _O can be calculated.

Next, the time history waveform of the noise level L and grounds the noise level L _T created by the noise waveform processing section 55, which is data stored in the hard disk 29.

  After the sound pressure measurement by the cc microphone 12 and the noise measurement by the sound level meter 13 are appropriately performed, a desired time at which reproduction is to be started is input as a specified time via the time specifying unit 52, and then a composite image is created. The unit 54 reads out from the hard disk 27 the arrival angle of the sound pressure measurement time that matches the input specified time as the synthesis target arrival angle.

  Next, the composite image creation unit 54 creates a composite image by superimposing the direction display image corresponding to the composition target arrival angle on the planar arrangement image, and outputs this to the monitor 26.

On the other hand, the noise waveform processing section 55 reads out the time history waveform of the noise level L and grounds the noise level L _T from the hard disk 29, an image displaying a playback position marker at a position on the time history waveform that matches the specified time described above Then, a time history waveform image is obtained, and the time history waveform image is output to the monitor 26.

FIG. 6 shows the display state of the monitor 26 when the playback time is designated as time t ₁ by sliding the graphic interface (not shown) on the monitor 26 constituting the time designation unit 52 with the mouse 28. The monitor is directed to a plane arrangement image showing two crawler cranes 65a and 65b and a tower crane 66 operating in the site 2 and a boom turning range of the tower crane 66. a composite image 61 arrow graphic 63 as a display image is superimposed starting from the measurement point, a time history waveform comprising the overlaid playback position marker 64 at each time history waveform of the noise level L and grounds the noise level L _T image 62 and have been displayed, the playback position marker 64 is a reproducing timing of the combined image 61, on-site noise level L _T It is shown that is greater than the target value.

Here, on the extension of the arrow graphic 63, since the crawler crane 65a is present, the noise source site noise level L _T causes that exceeds the target value at time t ₁ is that it is a crawler crane 65a It can be estimated, and it can be determined that noise countermeasures for stopping the crawler crane 65a should be taken at this point.

On the other hand, FIG. 7 similarly shows the display status of the monitor 26 when the reproduction time is designated at time t _{2. In} FIG. 7, the arrow figure 63 faces the outside of the site 2, playback position marker 64 is a reproducing timing of the combined image 61, but the noise level L is higher than the target value, on-site noise level L _T indicates that below the target value.

Thus, the noise level L exceeds the target value at time t _2, the off-site source, for example, an automobile is a major cause that becomes the noise source, the on-site noise level L _T is less than the target value Therefore, it can be determined that there is no need to take special noise countermeasures within the site 2.

  As described above, according to the noise source search system 1 according to this embodiment, the sound pressure of the generated sound is measured by the cc microphone 12 and the arrival angle calculation unit 44 using the measured sound pressure value. To calculate the arrival angle of the generated sound, and set the arrival angle as the synthesis target arrival angle, and the arrow figure 63 directed in the direction on the planar arrangement image corresponding to the synthesis target arrival angle as the starting point Since the composite image 61 is created by superimposing it on the planar arrangement image and displayed on the monitor 26, it is possible to confirm where the generated sound is coming from on the planar arrangement diagram, thus noise. The location of the source can be identified appropriately and quickly.

In addition, according to the noise source search system 1 according to the present embodiment, the noise level meter 13 that measures the sound pressure of the generated sound as the noise level is additionally provided, and the influence rate C (θ) and the noise level L are used. allocation noise level site noise level L _T, since to output to the monitor 26 of them as time history waveform, the target of the noise monitoring, without the noise level L are reflected all the generated sound, site 2 Is a noise level for each angle reflecting only the sound generated from the angle range over which the

Therefore, it is sufficient to search for a noise source only when the noise level _T in the site exceeds the target value, and the noise level is generated by sound generated from other than the site 2, for example, sound generated from a car traveling on a surrounding road. There is no need to search for a noise source until the search for the noise source is essentially unnecessary, which exceeds the target value.

  In addition, even when a search for a noise source is necessary, it is possible to immediately confirm where the generated sound is coming from on the plane layout as described above, so that the position of the noise source can be appropriately and quickly determined. It becomes possible to specify.

  Further, according to the noise source search system 1 according to the present embodiment, the time at which reproduction is to be started is designated via the time designation unit 52, and the synthesis target arrival angle whose sound pressure measurement time coincides with the designated time is set to the hard disk 27. Since the composite image creation unit 54 superimposes it on the planar layout image, it is possible to check and examine noise countermeasures using the past composite image. For example, the composite data stored all day is stored. While viewing the image, it is possible to grasp the state of the sound generated on the previous day, confirm the effect of noise countermeasures, or examine new countermeasures.

Further, according to the noise source search system 1 according to this embodiment, the time history waveform of the noise level L and grounds the noise level L _T as well as created in the noise waveform processing section 55, playback position on the time history waveform Since the position marker 64 is displayed as an image of the time history waveform, and the time history waveform image is output to the monitor 26, the noise level at the same time as the synthesized image and the noise level in the site are Since the position of the time history waveform is indicated by the reproduction position marker 64, it becomes possible to more carefully study noise countermeasures using past synthesized images.

  In the present embodiment, the arrival angle data calculated from the measured sound pressure value is stored in the hard disk 27, and among these, the one whose sound pressure measurement time matches the specified time is read out. In other words, instead of the recording / playback mode, it is possible to perform processing by time-shifted playback (chasing playback), and as shown in FIG. 8, the hard disk 27 and the time designation unit 52 are omitted and processing is performed in real time mode. Is also possible.

  In this case, the arrival angle calculated by the arrival angle calculation unit 44 becomes the synthesis target arrival angle, and the arrow graphic 63 directed in the direction corresponding to the synthesis target arrival angle is converted into a planar arrangement image by the composite image creation unit 54. Although the images are superimposed, the current situation is displayed as a composite image on the monitor 26. In the case shown in FIG. 6, the crawler crane 65a can be quickly stopped, and FIG. In such a case, it is possible to take measures such as continuing the noise monitoring while maintaining the current state.

In the case of this modification, the noise level L and grounds the noise level L _T, is possible to display images on the monitor 26 as the value of the time history waveform to date in the same manner as FIGS. 6 and 7, or at the moment Although possible, the playback position marker 64 is omitted.

Further, in the present embodiment, to display the time history waveform image 62 to create a noise indices such noise level L and grounds the noise level L _T as a time history waveform comprising over playback position marker 64 is superimposed on its monitor 26 However, instead of each time history waveform, the numerical value of each noise index at the time of reproduction may be displayed, and the reproduction time may be displayed instead of the reproduction position marker 64.

  In such a configuration, it is difficult to grasp the fluctuation state of the generated sound within a certain time, but noise monitoring in which a noise index and a composite image are associated with each other is possible as in the above-described embodiment.

  Further, in the present embodiment and the above-described modification, the sound level meter 13 is provided. However, in some cases, the noise level processing unit 55 that performs processing using the sound level meter 13 and the measurement result thereof may be omitted. It doesn't matter.

  FIG. 9A shows an application of this modification to the real-time mode. In the configuration shown in the figure, noise monitoring based on the conventional noise regulation cannot be performed, but a composite image is created by superimposing the arrival angle as an arrow figure on the plane layout diagram, and this is displayed on the monitor 26. By displaying, the sound source of the generated sound can be confirmed on the planar layout, and the search for the noise source can be efficiently performed thereby, which is no different from the above-described embodiment. In the modified example shown in FIG. 10, since the noise meter 13 is omitted, it is not necessary to perform matching related to auditory correction, so that the filter unit 41 is also unnecessary.

  Further, as shown in FIG. 9B, a microphone 91 having a configuration according to the pp method, for example, can be used in place of the sound pressure measuring means instead of the cc microphone 12.

  On the other hand, as shown in FIG. 9 (c), a noise level meter 13 may be added to the configuration of FIG. 9 (b) and the noise level measured by the noise level meter may be displayed on the monitor 26. In such a configuration, the noise level for each angle, in particular, the noise level in the site is not calculated, and only the noise level is displayed. Therefore, the construction machine operating in the site 2 becomes the noise level with respect to the measured noise level. Although it is not possible to grasp how much influence is exerted, there is no difference that the arrival angle of the generated sound is displayed as an arrow graphic 63 superimposed on the planar arrangement image as in FIG. 6 and FIG. It is generally possible to determine which construction machine may be the source of noise.

  Further, in the present embodiment, when the number of arrivals of the generated sound is counted by the arrival frequency counting unit 45 for each arrival angle using the arrival angle data obtained by the arrival angle calculating unit 44, each time the generated sound arrives, However, instead of this, the arrival angle calculation unit is configured so that the magnitude of the energy of the generated sound is calculated as the energy value of the generated sound, and the number of generated sound arrivals May be configured to be weighted with the energy value of the generated sound.

That is, in the arrival angle calculation unit, the following equation is obtained from the sound pressures p ₁ and p ₂ measured by the microphone pair including the microphones 12a and 12b:
E _P = (p ₁ + p ₂ ) ²
Is calculated to calculate the energy E _P of the generated sound.

The energy E _P calculated by the arrival angle calculation unit may be appropriately stored in a storage device such as a hard disk as necessary. Instead of the microphone pair consisting of the microphones 12a and 12b, the energy E _{P of the} generated sound is calculated using the sound pressure measured by the microphone pair consisting of the microphones 12c and 12d or the microphone pair consisting of the microphones 12e and 12f. It doesn't matter if you do.

  Next, as in the above-described embodiment, the arrival frequency counting unit counts the number of arrivals of the generated sound for each arrival angle using the arrival angle data obtained by the arrival angle calculation unit, but simply increments “1”. Instead of accumulating, the number of times weighted by the energy value is accumulated.

That is, if the energy value of the generated sound arriving at the kth (1 ≦ k ≦ M) among the generated sounds arriving at the arrival angle θ is E _P (k), the number _N ′ of generated sounds arriving at the arrival angle. (θ) is expressed by the following equation:
_{N ′} (θ) = Σ (1 · E _P (k)) (k = 1, 2,... M)
Calculate with

  According to such a modification, when the number of arrivals of the generated sound is counted, the number of arrivals is weighted by the magnitude of the generated sound energy. Therefore, the influence rate and the noise level in the site are also determined by the magnitude of the generated sound energy. Using the generated sound that is weighted, that is, the influence on the noise becomes more dominant, the influence rate and the noise level in the site are calculated, and thus rational noise monitoring becomes possible.

  In addition, the weighting described above makes it possible to appropriately grasp the arrival angles of the generated sounds even when the generated sounds arrive from various angles.

Although not particularly mentioned in the present embodiment, as shown in FIG. 10, in place of the arithmetic processing unit 22, a predetermined target value the size of the on-site noise level L _T to the arithmetic processing unit In comparison, the construction of the alarm creation unit 47 for creating alarm data when the noise level in the site exceeds the target value is provided, and the grandchild machine 31 is installed in the construction machine 3 operating in the site 2 Then, the grandchild machine may be provided with the alarm output unit 32, and the alarm output unit may be configured to output the alarm data generated by the alarm generation unit 47.

  The alarm output unit 32 can be configured using a portable information terminal attached to the driver's seat of the construction machine 3, and in such a case, an alarm button blinks on the screen of the portable information terminal. Or an alarm color from the speaker of the portable information terminal, and the alarm data to be generated by the alarm generation unit 47 is the alarm data to be generated. What is necessary is just to produce suitably according to the structure of the output part 32. FIG.

According to this modification, as well as create a warning data in the alarm generating unit 47 when the on-site noise level L _T is above the target value, the said alarm data, the transmitting unit and grandchild provided the parent device 21 Since it is received via a receiving unit (not shown) provided at 31 and output to the alarm output unit 32, it is possible to take real-time noise countermeasures for the construction machine 3 in the site 2 It becomes.

  Although not specifically mentioned in the present embodiment, in addition to the auditory sensation correction circuit, the filter unit 41 is provided with a heavy machinery selection circuit that performs filtering with the frequency characteristics of the generated sound according to the type of the construction machine 3. May be.

  The heavy equipment sorting circuit investigates the frequency characteristics of the sound generated by each heavy machine by analyzing the frequency of the sound generated by the operation of various construction machines such as bulldozers, tractor excavators, and backhoes. The generated sound can be selectively passed and can be switched to each other. It is desirable that the frequency characteristic unique to each heavy machine is also distinguished from the frequency characteristic of running sound in a general passenger car or train.

  According to such a configuration, it is possible to extract only the measurement value caused by a specific construction machine from the measurement value obtained by the cc microphone 12, and noise monitoring for a specific construction machine can be performed. It becomes possible.

  In the modified example in which the grandchild machine 31 is installed in the construction machine 3 and the grandchild machine is provided with the alarm output unit 32, the heavy machine is separated while filtering is performed on a specific construction machine. It is desirable that the alarm data be received by the grandchild machine 31 installed in the construction machine when the noise level in the site exceeds the target value.

  As a specific configuration, for example, heavy machine information to be filtered is stored in the noise index creating unit 46 in conjunction with the switching operation of filtering, and if the noise level in the heavy machine site exceeds the target value, the noise index is created. When determined by the unit 46, the alarm creation unit 47 is configured to read the stored heavy machine information and include the heavy machine information in the alarm data, and the alarm data is stored in the portable information of the target construction machine. It is conceivable that the alarm output unit 32 is configured to be output to the terminal.

[Second Embodiment]
Next, a second embodiment will be described. In addition, about the substantially same components etc., the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  FIG. 11 is an overall block diagram and site layout diagram showing a noise source search system according to the second embodiment. As can be seen from the figure, the noise source search system 1 'according to the present embodiment is applied to the noise monitoring of the construction machine 3 operating in the site 2 which is the noise monitoring area, as in the first embodiment. In the vicinity of the boundary of the site 2, the side of the general road 4 and the left side orthogonal to the general road 4 are set as measurement points, respectively, and are provided in the slave units 11A and 11B arranged at the two measurement points. Cc microphones 12A and 12B as sound pressure measuring means, sound level meters 13A and 13B as noise measuring means, and a main unit 21 'disposed in a construction office 6 standing on the site 2 And an arithmetic processing unit 22 ′.

  Here, the cc microphones 12A and 12B have the same configuration as that of the cc microphone 12, and the sound level meters 13A and 13B have the same configuration as that of the sound level meter 13, respectively, and therefore description thereof is omitted here.

  On the other hand, the base unit 21 ′ is composed of a receiving unit 23 that receives transmission data wirelessly transmitted from the transmitting units 17A and 17B of the slave units 11A and 11B and a personal computer 24, and the arithmetic processing unit 22 ′ described above. Is composed of hardware such as a motherboard, a CPU, a memory, and a built-in hard disk of the personal computer 24 and software that operates on the hardware.

  As shown in FIG. 12, the arithmetic processing unit 22 ′ uses the sound pressure measurement values received by the cc microphones 12 </ b> A and 12 </ b> B via the reception unit 23 as the frequency weighting characteristics built in the sound level meters 13 </ b> A and 13 </ b> B. A filter unit 41 ′ provided with an auditory correction circuit for filtering by the A characteristic, an arrival angle calculation unit 44 ′ for calculating the arrival angles of generated sounds at two measurement points using output data from the filter unit, and The arrival angles at the two measurement points at the sound pressure measurement time that coincides with the designated time input via the time designation unit 52 are read out from the hard disk 27 as the synthesis target arrival angles, and the direction display corresponding to each synthesis target arrival angle. A composite image is generated by superimposing the images on the planar layout image, and the composite image is generated and output to the monitor 26. The direction display image is an arrow graphic that is superimposed on the planar arrangement image so that the positions on the plane arrangement image corresponding to the two measurement points are set as starting points. It is configured.

On the other hand, the arithmetic processing unit 22 ′ uses the arrival angle data at the two measurement points obtained by the arrival angle calculation unit 44 ′ to count the number of arrivals of the generated sound in the time width Δt for each arrival angle. Unit 45 ′, the number of arrivals N (θ) for each angle of arrival obtained by the arrival frequency counting unit, and the noise level L by the sound level meters 13A and 13B transmitted via the receiving unit 23 time specification section 52 with the noise indices in the measurement point to create a noise index creation unit 46 'to create respectively as the noise level L and grounds the noise level L _T, a time history waveform of the noise level L and grounds the noise level L _T The reproduction position marker is displayed as an image at a position on the time history waveform that coincides with the specified time input via the signal, and the time history waveform image is output to the monitor 26 as a noise history processing. It provided with a part 55 '.

  Here, the filter unit 41 ′, the arrival angle calculation unit 44 ′, the composite image creation unit 54 ′, the arrival frequency counting unit 45 ′, the noise index creation unit 46 ′, and the noise waveform processing unit 55 ′ correspond to two measurement points. The filter unit 41, the arrival angle calculation unit 44, the composite image creation unit 54, the arrival frequency counting unit 45, the noise index creation unit 46, and the noise waveform processing unit 55 described in the first embodiment are the same as those described in the first embodiment. Although they are different, they can be configured by providing them in parallel, for example, and therefore the description thereof is omitted here.

  In order to monitor the noise caused by the construction machine 3 operating in the site 2 by using the noise source search system 1 ′ according to the present embodiment, the noise pressure is set to the sound pressure of the generated sound at the two measurement points. While measuring with a total of 13A and 13B, the sound pressure of the sound generated at two measurement points is also measured with the cc microphones 12A and 12B, and these are transferred to the master unit 21 '. It is assumed that the slave units 11A and 11B are installed so that the x-axis of the cc microphones 12A and 12B is directed to the right in FIG.

  As in FIG. 4A, the generated sound is caused by the construction machine 3 in the site 2 and the vehicle 5 traveling on the general road 4 at the measurement point on the general road 4 side. The sound level meter 13A measures the noise level in all directions in the synthesized state, and at the measurement point on the side orthogonal to the general road 4, the construction machine in the site 2 is roughly classified. However, the sound level meter 13B measures the noise level in all directions in the synthesized state.

Next, according to the same procedure as in the first embodiment, the arrival angle of the generated sound is calculated by the arrival angle calculation unit 44 ′ using the sound pressure values measured by the microphones 12a to 12f, which is the basis for the calculation. While the data is stored in the hard disk 27 together with the sound pressure measurement time of the sound pressure value, the number of arrivals of the generated sound for each arrival angle is counted by the arrival frequency data using the arrival angle data, and the arrival number for each arrival angle. Is divided by the sum of all directions, and the influence rate for each angle of arrival is calculated by the noise index creation unit 46 ′. The noise level creation unit continuously calculates the noise level L _T in the site, and the noise level L and the site level are calculated. This data stored in the hard disk 29 the time history waveform of the noise level L _T created by the noise waveform processing unit 55 '.

  These procedures are performed every two measurement points.

  Next, the composite image creation unit 54 ′ creates a composite image by superimposing the direction display image corresponding to the composition target arrival angle on the planar layout image at every two measurement points, and outputs this to the monitor 26.

On the other hand, the noise waveform processing unit 55 ', a time history waveform of the noise level L and grounds the noise level L _T in the two measuring points read from the hard disk 29, the position on the time history waveform that matches the specified time described above The reproduction position marker is displayed as an image to obtain a time history waveform image, and the time history waveform image is output to the monitor 26.

FIG. 13 shows the display state of the monitor 26 when the playback time is designated as time t ₁ by sliding the graphic interface (not shown) on the monitor 26 constituting the time designation unit 52 with the mouse 28. The monitor is directed to a plane arrangement image showing two crawler cranes 65a and 65b and a tower crane 66 operating in the site 2 and a boom turning range of the tower crane 66. A composite image 61 ′ in which the arrow graphics 63 </ b> A and 63 </ b> B as display images are overlapped starting from the two measurement points A and B, the noise level L and the site noise level L _T for each of the two measurement points A and B A time history waveform image 62 ′ in which a reproduction position marker 64 is superimposed on each time history waveform is displayed. In reproduction timing of the combined image 61 ', one of the measurement point A, site noise level L _T even B indicates that exceeds the target value.

Here, on the extension of the arrow graphic 63B, crawler cranes 65a, although 65b is present, on the extension of the arrow graphic 63A, since there is only a crawler crane 65b, on-site noise level L _T at time t ₁ The noise source that causes the target value to be exceeded can be estimated to be the crawler crane 65b, and it can be determined that noise countermeasures for stopping the crawler crane 65b should be taken at this point.

On the other hand, FIG. 14 similarly shows the display state of the monitor 26 when the reproduction time is designated at time t ₂ , and in FIG. 14, the arrow graphic 63B faces the inside of the site 2. The arrow figure 63A faces the outside of the site 2, and the reproduction position marker 64 has a noise level L that exceeds the target value at the measurement point A at the reproduction timing of the composite image 61 ′. _T indicates that is below the target value, which at the measurement point B, none of the noise level L and grounds the noise level L _T is below the target value.

From these facts, the reason why the noise level L exceeded the target value at the measurement point A at time t ₂ is largely due to the fact that a sound source outside the site, for example, a car, became the noise source. since L _T are both smaller than the target value, it can be determined that there is no need to take special noise countermeasures in the premises 2.

  As described above, according to the noise source search system 1 ′ according to the present embodiment, the sound pressure of the generated sound at the two measurement points is measured by the cc microphones 12 </ b> A and 12 </ b> B, respectively, and the measured sound pressure is measured. The arrival angle of the generated sound is calculated by the arrival angle calculation unit 44 ′ using the value, and the arrival angle is set as the synthesis target arrival angle and is directed in the direction on the planar arrangement image corresponding to the synthesis target arrival angle. Since the arrow graphic 63A, 63B is superimposed on the planar arrangement image with the measurement points A, B as starting points, a composite image 61 ′ is created and displayed on the monitor 26, so that it is generated as in the first embodiment. It is possible to confirm where the sound comes from on the plan layout, and thus the position of the noise source can be identified appropriately and quickly.

  In particular, according to the noise source search system 1 ′ according to the present embodiment, the sound pressure of the generated sound is measured at the two measurement points A and B, thereby calculating the arrival angles of the generated sound at the measurement points. Since the result is superimposed on the planar arrangement image as two arrow figures 63A and 63B, the noise source can be searched more reliably.

  In addition, although the effect similar to the other effect described in 1st Embodiment is exhibited also in this embodiment, the description is abbreviate | omitted here. Further, each modification described in the first embodiment can also be applied to this embodiment, but the description thereof is also omitted here.

DESCRIPTION OF SYMBOLS 1, 1 'Noise source search system 2 Site 3 Construction work machine 11, 11A, 11B Child machine 12, 12A, 12B cc microphone (sound pressure measuring means)
12a to 12f Microphones 13, 13A, 13B Sound level meter (noise measuring means)
21, 21 ′ Base unit 22, 22 ′ Operation processing unit 26 Monitor (display means)
27 Hard disk (sound pressure related data storage means)
31 grandchild machine 32 alarm output unit 41, 41 'filter unit 44, 44' arrival angle calculation unit 45, 45 'arrival frequency counting unit 46, 46' noise index creation unit 47 alarm creation unit 52 time designation unit 54, 54 'synthesis Image creation unit 55, 55 'Noise waveform processing unit 61, 61' Composite image 62, 62 'Time history waveform image 63, 63A, 63B Arrow figure (direction display image)
64 Playback position marker

Claims (12)

Sound pressure measuring means for measuring the sound pressure of the generated sound at a measurement point set near the boundary of the site, which is a noise monitoring area, and the arrival of the generated sound using the sound pressure value measured by the sound pressure measuring means An arrival angle calculation unit for calculating an angle, and an arrival angle obtained from the arrival angle calculation unit as a synthesis target arrival angle, a direction display image corresponding to the synthesis target arrival angle is a plane layout diagram of the sound source arrangement status in the site And a composite image creation unit that creates a composite image by superimposing the image on the planar placement image at a corresponding position of the measurement point, and a display unit that displays the composite image. A noise source search system. The sound pressure measuring means is configured so that the sound pressure values of the generated sound are respectively measured at the two measurement points by using the two measurement points as different measurement points, and the sound measured at the two measurement points. The arrival angle calculation unit is configured such that the arrival angles at the two measurement points are respectively calculated as two synthesis target arrival angles from the pressure value, and the composite image creation unit is set to each of the two synthesis target arrival angles. The noise source search system according to claim 1, wherein the corresponding direction display image is the planar arrangement image and is superimposed on the corresponding positions of the two measurement points on the planar arrangement image. The sound pressure measuring means is arranged such that two microphones having directivity are arranged so that the maximum sensitivity directions are opposite to each other, and the microphone pairs are set along a plurality of axes that are not parallel to each other and their origins are set. The noise source search system according to claim 1 or 2, wherein the noise source search system is arranged so as to be sandwiched therebetween. 4. The apparatus according to claim 1, further comprising a noise measuring unit that is disposed in the vicinity of the measurement point and measures a sound pressure of a generated sound as a noise level, and that outputs the noise level to the display unit. The described noise source search system. A noise measuring means arranged near the measurement point for measuring the sound pressure of the generated sound as a noise level;
An auditory correction circuit is provided for filtering the sound pressure value measured by each microphone with a frequency weighting characteristic substantially the same as the frequency weighting characteristic incorporated in the noise measuring means, and the processing result is output to the arrival angle calculation unit. A filter section to perform,
An arrival frequency counting unit that counts the number of arrivals of the generated sound in a predetermined time width for each arrival angle using the arrival angle obtained by the arrival angle calculation unit;
Dividing the number of arrivals for each arrival angle obtained by the arrival frequency counting unit by the sum of all directions to calculate the influence rate for each arrival angle, and overlooking the site using the influence rate and the noise level A noise index creating unit configured to calculate a noise index due to a generated sound within an angular range as a site noise level and output the site noise level together with the noise level to the display means. Item 4. The noise source search system according to Item 3. The noise source search system according to claim 5, further comprising a noise waveform processing unit that creates a time history waveform of the noise level or the noise level in the site in addition to the noise level and outputs the time history waveform to the display means. Sound pressure-related data storage means for storing the sound pressure value measured by the sound pressure measurement means or the arrival angle calculated by the arrival angle calculation unit using the sound pressure value, and time designation for specifying the reproduction time Means for reading the sound pressure value at the sound pressure measurement time coinciding with the designated time inputted via the time designation means from the sound pressure related data storage means, and using the sound pressure value, the angle-of-arrival calculation unit The arrival angle calculated in step S3 is used as the synthesis target arrival angle, or the arrival angle at the sound pressure measurement time that coincides with the specified time is read from the sound pressure related data storage unit and is used as the synthesis target arrival angle. The noise source search system according to claim 5, wherein the synthesis target arrival angle is output to the synthesized image creation unit. A time history waveform of the noise level or in addition to the noise level in the site is created, and a reproduction position marker is displayed as an image at a position on the time history waveform that coincides with the designated time input via the time designation means. The noise source search system according to claim 7, further comprising a noise waveform processing unit that generates a time history waveform image and outputs the time history waveform image to the display means. The arrival angle calculation unit is configured such that the magnitude of the energy of the generated sound is calculated as an energy value for each generated sound, and the arrival frequency counting unit is configured so that the number of arrivals of the generated sound is the generated sound. The noise source search system according to any one of claims 5 to 8, wherein the noise source search system is configured to be weighted by energy values. A heavy machine selection circuit that filters the measurement values of each microphone with a frequency characteristic according to the type of construction machine in the site is provided in the filter unit, and the noise level in the site is set as a noise level in the site for each heavy machine. The noise source search system according to any one of claims 5 to 9. The noise level in the site or the noise level in the site by heavy machinery is compared with a predetermined target value, and alarm data is output when the noise level in the site or site noise level by heavy machinery exceeds the target value. The noise source search system according to any one of claims 5 to 10, further comprising: an alarm generation unit that generates an alarm output unit that outputs alarm data generated by the alarm generation unit. The noise source search system according to claim 11, wherein the alarm output unit is provided in a construction machine operating in the site.

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