JP2913692B2 - Abnormal noise vehicle detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an abnormal noise vehicle sensing device that generates noise (abnormal noise) exceeding a prescribed level.

<Related Art> A runaway vehicle that runs on a road while producing abnormal noise by improving or removing a muffler has caused a great deal of trouble to residents along the road, and has become a social problem as noise pollution.

Conventionally, the appearance of abnormal noise vehicles has only been determined by reporting to the police from inhabitants and passers-by or by patrols by police stations.

However, it is not always the case that roadside residents and passers-by report, and even if they do, there may be a delay in hesitating until they decide to report, or it may take a long time to answer the phone, Even if a patrol car that receives radio communication rushes to the site, in most cases abnormal noise vehicles have already escaped, and effective enforcement has not been achieved at present. In addition, the probability that a patrol car during a patrol encounters an abnormal noise vehicle is not very high.

Therefore, a terminal device equipped with an acoustic sensor such as a microphone for detecting abnormal noise is installed at key points along the road, an acoustic signal is detected by the acoustic sensor of the terminal device, and the sound level data obtained by digitally converting the sound signal is obtained. By transmitting to the central device at the monitoring center together with the terminal device identification data, the appearance of the abnormal noise vehicle and its site are detected,
A police system was considered, in which a patrol car that received wireless communication from the monitoring center rushed to the site.

According to such a system, the appearance of the abnormal noise vehicle and the appearance place thereof can be detected constantly and in real time.

By the way, the traveling amount of the abnormal noise vehicle is not so large as compared with the ordinary vehicle. Therefore, installing a terminal device equipped with the above-described acoustic sensor (microphone) and its peripheral circuits at key elements along the road just for the purpose of controlling abnormal noise vehicles is costly for the efficiency of control. It is unavoidable to be expensive.

Therefore, in order to grasp the traffic volume and traffic congestion, etc., the ultrasonic vibrator provided in the ultrasonic vehicle sensor currently installed along the road should also be used as an acoustic sensor for detecting abnormal noise vehicles. Thus, it is conceivable to reduce the cost.

<Problems to be solved by the invention> However, when the ultrasonic vibrator is also used as an acoustic sensor for detecting abnormal noise vehicles, the sensitivity range of the ultrasonic vibrator is deviated from the human audible sound range. The following problems occur.

(B) Even if the sound level of the audible sound range that humans perceive exceeds the specified level that is noisy, if the sound level of the ultrasonic region detected by the ultrasonic transducer is lower than the specified level, it is detected as abnormal noise caused by a runaway vehicle Can not do.

(B) Even if the sound level in the ultrasonic range exceeds the specified level, if the cause is due to city noise, whether or not the sound level in the audible sound range exceeds the specified level, whether it is abnormal due to a runaway vehicle or not. It cannot be judged as noise.

(C) Ultrasonic waves emitted from the ultrasonic transducer and reflected from the vehicle and returned to detect the passage of the vehicle are picked up by the ultrasonic transducer, and when it exceeds a specified level, abnormal noise caused by a runaway vehicle It cannot be judged. This is because a general vehicle that does not generate abnormal noise is erroneously recognized as an abnormal noise vehicle.

As described above, when the ultrasonic transducer in the ultrasonic vehicle sensor is also used as an acoustic sensor for abnormal noise vehicle detection, if the acoustic signal received by the ultrasonic transducer is determined only at the sound level, There is a problem that it is not possible to distinguish between reflected ultrasonic waves or city noise from vehicles and abnormal noise from runaway vehicles.

The present invention has been made in view of such circumstances, and low cost has been achieved by also using an ultrasonic vibrator provided in an ultrasonic vehicle sensor as an acoustic sensor for detecting abnormal noise vehicles. It is another object of the present invention to make it possible to clearly distinguish abnormal noise caused by a runaway vehicle from reflected ultrasonic waves from a general vehicle and urban noise by using the same.

<Means for Solving the Problems> The present invention has the following configuration to achieve such an object.

That is, the abnormal noise vehicle sensing device according to the present invention includes an acoustic sensor that receives a sound emitted from the vehicle, a camera that photographs the vehicle, and outputs image data of the photographed image, and an acoustic signal received by the acoustic sensor. An abnormal noise vehicle determining means for converting to a frequency spectrum and comparing with a frequency spectrum stored in advance to determine whether or not the vehicle is an abnormal noise vehicle; and It is characterized by outputting the identification data of the sensing device itself and the image data obtained by the camera.

<Operation> The operation of the above configuration of the present invention is as follows.

Abnormal noise vehicles with modified or removed mufflers
Since the explosion impact noise generated by the engine is directly exhausted through the exhaust pipe, the exhaust noise in the ultrasonic range is a unique frequency spectrum completely different from reflected ultrasonic waves from ordinary vehicles and urban noise. Have.

The frequency spectrum specific to such an abnormal noise vehicle is stored in a memory in advance, and the frequency spectrum of the acoustic signal received by the ultrasonic vibrator is compared with the frequency spectrum specific to the abnormal noise. Can be distinguished from reflected ultrasonic waves from ordinary vehicles and urban noise.

<Example> Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

As shown in FIG. 5, an ultrasonic vehicle sensor A has an arm 2 extending above a vehicle running belt on a road fixed to an upper end of a pole 1 erected on a roadside. The transducer 3 is attached to the road surface.

As shown in FIG. 6, the ultrasonic transducer 3 comprises an umbrella-shaped reflector 4 having an apex angle of approximately 90 degrees and an ultrasonic transducer 5 attached to the center of the umbrella-shaped reflector 4. It is configured.
The ultrasonic vibrator 5 is composed of a piezoelectric body 5a formed in a cylindrical shape from PZT (lead zirconate titanate) or the like, and electrodes 5b and 5c joined to the inner and outer peripheral surfaces of the piezoelectric body 5a. ing.

The two electrodes 5b and 5c are connected to a transducer 7 built in a processing device 6 installed at the base of the pole 1 shown in FIG. The transmitter / receiver 7 includes a transmitter that outputs an excitation signal at fixed time intervals, and a receiver that inputs a reception signal during a period in which the excitation signal is not output.

When an AC excitation signal is applied to both electrodes 5b and 5c from the transmitter of the transmitter / receiver 6, the ultrasonic vibrator 5 vibrates and emits ultrasonic waves. The reflected ultrasonic waves are emitted along the axial direction.

When a running or stopped vehicle is present on the ultrasonic emission line, the ultrasonic waves reflected from the vehicle are collected by the umbrella-shaped reflector 4 and incident on the ultrasonic transducer 5. As a result, the piezoelectric body 5a of the ultrasonic vibrator 5 is vibrated, and an AC reception signal corresponding to the level and frequency of the reflected ultrasonic wave is generated between the electrodes 5b and 5c. 7 is input to the receiver.

The received signal received by the transmitter / receiver 7 is transmitted as a vehicle detection signal to the traffic control center B via a communication line 8 such as a radio wave line or an optical fiber as shown in FIG. I have.

The ultrasonic vehicle sensors A as described above are installed at important points along the road, and the transducers 7 of each ultrasonic vehicle sensor A are connected to the traffic control center B via the communication line 8 respectively. I have. In the traffic control center B, each ultrasonic vehicle detector A
Is displayed on the graphic panel 9 based on the vehicle detection signal sent from the vehicle.

The abnormal noise vehicle sensing device of the present embodiment also uses the ultrasonic transducer 5 in the existing abnormal noise vehicle sensing system configured as described above as an acoustic sensor for sensing abnormal noise caused by a runaway vehicle.

FIG. 1 is a block diagram showing the electrical configuration of such an abnormal noise vehicle sensing device.

As shown in the drawing, the abnormal noise vehicle sensing device C includes an ultrasonic vibrator 5 (electrodes 5b and 5) provided in the ultrasonic vehicle sensor A.
c), and removes the excitation signal from the transducer 7 so that the ultrasonic transducer 5 receives the ultrasonic wave (20 to 30 KH).
z) A band elimination filter (BE
F) 10, an amplifier 11 for amplifying the acoustic signal that has passed through the band elimination filter 10, a frequency spectrum converter 12 for converting the amplified acoustic signal into a frequency spectrum SP _IN ,
For example, an abnormal noise frequency spectrum memory 13 previously storing a unique frequency spectrum SP _REF in an ultrasonic region of abnormal noise due to a runaway vehicle as shown in FIG.
Abnormal noise vehicle determination means for comparing the two frequency spectra SP _IN and SP _REF to determine whether the difference is within a reference range, and outputting an abnormal noise vehicle detection signal S _ABN when the difference is within the reference range. (MPU: Motorola central processing unit) 14 and modem (modem)
It is composed of 15 and.

In FIG. 3, P ₁ and P ₂ are specific frequency components generated when the muffler is modified or removed. The frequency spectrum of only P ₁ and P ₂ is not adopted as the unique frequency spectrum SP _REF , because the frequency components of P ₁ and P ₂ also appear in the frequency spectrum of the acoustic signal other than the abnormal noise caused by the runaway vehicle. , P ₁ and P ₂ may show a spectrum completely different from that of FIG.
This is because comparison with only P ₁ and P ₂ may make it impossible to distinguish abnormal noise caused by a runaway vehicle from other sounds.

The frequency spectrum converter 12 is configured as shown in FIG. 2 (a) or FIG. 2 (b).

The frequency spectrum converter 12 shown in FIG. 2A is connected to the next stage of the amplifier 11 so that the sensitivity range (20
-30 KHz) into multiple frequency bands, a plurality of band-pass filters (BPF) 16, a plurality of rectifiers 17 for rectifying the frequency signals split by the respective band-pass filters 16 into DC signals, and an output of each rectifier 17. a multiplexer (MPX) 18 for sequentially outputting the divided scan time signals, an a / D converter 19 for output to the microprocessor 14 creates a frequency spectrum SP _iN converts the individual output signals into a digital signal It is a thing.

Further, the frequency spectrum converter 12 shown in FIG.
Is an A / D converter 20 that is connected to the next stage of the amplifier 11 and converts the amplified received acoustic signal into a digital signal, and that the A / D converter 20 performs high-speed sampling and fast Fourier transform (FFT). By frequency spectrum SP
_And a digital signal processor (DSP) 21 for generating _IN and outputting the _IN to the microprocessor 14.

The abnormal noise vehicle sensing device C configured as described above,
Processing device 6 in ultrasonic vehicle sensor A (see FIG. 5)
It is built in.

A pole 1 for supporting the ultrasonic transducer 3 shown in FIG.
An industrial TV camera 22 for photographing an abnormal noise vehicle is attached to the upper end of the TV camera 22.
As shown in FIG. 1, the microprocessor 14 is configured to start photographing when the microprocessor 14 outputs the abnormal noise vehicle detection signal S _ABN . The image data is data-compressed by an image compression circuit 23, output from the modem 15 together with the abnormal noise vehicle detection signal S _ABN from the microprocessor 14, and transmitted through the communication line 8a of the existing communication line 8. It is transmitted to the center B.

As shown in FIG. 4, the traffic control center B communicates with the modem 15 of the abnormal noise vehicle sensing device C through the modem 25 connected via the communication line 8a and all the received data. A memory 26 for storing, a display control unit 27,
The graphic panel 9 described above, an image expansion circuit 28 for expanding compressed image data, and a monitor display 29
, A console 30, and a memory 31 for evidence material.

In the traffic control center B, a graphic panel 9 and a plurality of monitor displays 29 are provided as shown in FIG. Graphic panel 9 is a road network map
A plurality of monitor displays 2 are arranged beside the graphic panel 9 in combination with a lamp 33 indicating the location of the abnormal noise vehicle sensing device C installed in the area indicated by the road network map 32. ing.

Next, the operation of the abnormal noise vehicle sensing device C of the present embodiment will be described.

The excitation signal output from the transmitter / receiver 7 in the ultrasonic vehicle sensor A and the signal in which the ultrasonic waves reflected from the vehicle are received by the ultrasonic vibrator 5 are transmitted to the band elimination filter 10.
And is not input to the amplifier 11.

When abnormal noise or city noise caused by a runaway vehicle is collected by the umbrella-shaped reflector 4 and is incident on the ultrasonic vibrator 5, the ultrasonic vibrator 5 receives sound in the ultrasonic region of the input sound, An AC signal corresponding to the frequency and level is output as a received acoustic signal. The received acoustic signal passes through a band elimination filter 10, is amplified by an amplifier 11, and is input to a frequency spectrum converter 12.

The frequency spectrum converter 12 converts the received received acoustic signal into a frequency spectrum SP _IN . The microprocessor 14 inputs the frequency spectrum SP _IN and, from the abnormal noise frequency spectrum memory 13, stores the frequency spectrum SP _REF specific to the abnormal noise caused by the runaway vehicle.
Is read. Then, both frequency spectra SP _IN and SP _REF
Are compared, and when it is determined that the difference between the two frequency spectra SP _IN and SP _REF is within the reference range, an abnormal noise vehicle detection signal S _ABN is output to the modem 15. When the difference is out of the reference range, the abnormal noise vehicle detection signal S _ABN is not output.

This makes it possible to clearly distinguish abnormal noise caused by a runaway vehicle from reflected ultrasonic waves from a general vehicle and urban noise. The microprocessor 14 generates an abnormal noise vehicle detection signal.
At the same time as outputting S _ABN , an activation signal is output to the television camera 22.

The TV camera 22 captures an image of the abnormal noise vehicle that generated the abnormal noise, compresses the image data by the image compression circuit 23, and converts the compressed image data into the abnormal noise vehicle detection signal S _ABN and the abnormal noise vehicle detection. The communication line 8a through the modem 15 together with the type number (ID) data of the device C
To send to. The traffic control center B is sequentially sent data from the plurality of abnormal noise vehicle sensing devices C.

In the traffic control center B, the data sent via the communication line 8a is stored in the memory 26 via the modem 25. The display control unit 27 reads the identification number data and the abnormal noise vehicle detection signal S _ABN from the memory 26, and blinks the lamp 33 on the graphic panel 9 corresponding to the identification number data.

Light flashing by controller on graphic panel 9
When the number of 33 and the number of the monitor display 29 are designated on the console 30, the display control unit 27 reads the corresponding compressed image data from the memory 26, and after this is decompressed by the image decompression circuit 28, Abnormal noise vehicle detection signal S _{ABN on} display 29
The image of the abnormal noise vehicle captured by the television camera 22 in the abnormal noise vehicle sensing device C that has output is displayed in real time.

The controller will also radio call the patrol car. As a result, the appearance location of the abnormal noise vehicle, the image of the abnormal noise vehicle, and the like are displayed on the display 34 mounted on the patrol car, and the patrol car can rush to the site.

At the same time, the controller operates the console 30,
The image data and the identification number data relating to the abnormal noise vehicle are read from the memory 26, and the abnormal noise occurrence time and other necessary data are added to the read data and registered in the evidence material memory 31.

Even if an abnormally noised vehicle flees when a patrol car rushes to the site, even if the vehicle has escaped, still image data and other evidence data showing the vehicle number, vehicle type, driver, passenger, etc. are stored in the evidence memory 31. Since it remains, it can be used effectively for later arrest.

As described above, according to the present embodiment, the unique frequency spectrum SP _REF in the ultrasonic range having abnormal noise caused by a runaway vehicle is stored in advance in the abnormal noise frequency spectrum memory 1.
3, the received acoustic signal from the ultrasonic transducer 5 is converted into a frequency spectrum SP _IN by the frequency spectrum converter 12, and the microprocessor 14
Compare both frequency spectra SP _IN and SP _REF and output the abnormal noise vehicle detection signal S _ABN when the difference is within the reference range. Can be clearly distinguished. Therefore, the ultrasonic vibrator 5 included in the ultrasonic vehicle sensor A can be used also as an acoustic sensor for detecting an abnormal noise vehicle, and the equipment cost can be reduced.

The present invention includes the following configuration as an embodiment.

(I) As a means for photographing an abnormal noise vehicle, a still television camera for photographing a still image may be used instead of the television camera 22 for photographing a moving image.

(Ii) Instead of displaying the location of the abnormal noise on the graphic panel 9, the location of the abnormal noise may be displayed on the monitor display 29 together with the image of the abnormal noise vehicle.

(Iii) Not only an existing ultrasonic vehicle sensor but also a new ultrasonic vehicle sensor may be used.

<Effects of the Invention> As described above, according to the present invention, the following effects are exhibited.

In other words, the explosion impact sound of the engine is directly emitted due to the modification or removal of the muffler. Abnormal noise The unique frequency spectrum in the ultrasonic range that has the exhaust sound of the vehicle is stored in advance in the abnormal noise frequency spectrum memory. The acoustic signal received by the ultrasonic transducer of the ultrasonic vehicle sensor is converted into a frequency spectrum by a frequency spectrum converter, and the frequency spectrum of the received acoustic signal and the abnormal noise frequency spectrum memory are determined by the determination means. Is compared with the frequency spectrum specific to the abnormal noise read out from the controller, and when the difference is within the reference range, the abnormal noise vehicle detection signal is output. It can be clearly distinguished from ultrasonic waves and urban noise to reliably detect only abnormal noise vehicles. Kill.

Therefore, as an acoustic sensor for detecting an abnormal noise vehicle, an ultrasonic vibrator included in an existing ultrasonic vehicle sensor can also be used, thereby making it possible to reduce equipment costs.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 to FIG. 7 relate to an embodiment of the present invention, FIG. 1 is a block diagram showing an electrical configuration of an abnormal noise vehicle sensing device and an ultrasonic vehicle sensor, FIG. (A) and (b) are block diagrams showing two examples of a specific configuration of the frequency spectrum converter, FIG. 3 is a characteristic diagram of a frequency spectrum of abnormal noise caused by a runaway vehicle, and FIG. 4 is a traffic control center. FIG. 5 is a block diagram showing an electrical configuration, FIG. 5 is an explanatory view of an installation state of an abnormal noise vehicle detecting device and an ultrasonic vehicle sensor, FIG. 6 is a schematic sectional view of an ultrasonic transducer, and FIG. FIG. 3 is a layout diagram of a graphic panel and a monitor display provided in a center. A: Ultrasonic vehicle detector 5: Ultrasonic transducer 12: Frequency spectrum converter 13: Abnormal noise frequency spectrum memory 14: Microprocessor (judgment means) SP _IN: Frequency spectrum SP _REF: Unique Frequency spectrum of S _ABN …… abnormal noise vehicle detection signal

Claims (1)

(57) [Claims] 1. An acoustic sensor for receiving a sound emitted from a vehicle, a camera for photographing the vehicle and outputting image data of the photographed vehicle, and a sound signal received by the acoustic sensor converted into a frequency spectrum and stored in advance. Abnormal noise vehicle determining means for comparing whether the vehicle is an abnormal noise vehicle by comparing the frequency spectrum with the noise spectrum, and identification data and a camera for the abnormal noise vehicle sensing device itself when the vehicle is determined to be an abnormal noise vehicle. And outputting the image data obtained in (1).