JP5252342B2 - Vehicle inspection device - Google Patents

Description

  The present invention relates to an inspection apparatus for inspecting a vehicle, particularly a completed vehicle.

  The vehicle is completed through welding, painting, assembly, and the like. The completed vehicle is called a completed vehicle. This completed vehicle is subjected to a final check called a completed vehicle inspection before being put on the market. This completed vehicle inspection includes a sound / vibration inspection for checking whether sound or vibration transmitted to the vehicle during traveling is within a certain level.

  Conventionally, the sound / vibration inspection has mainly been a sensory inspection by an inspector. Since the sensory test depends on the subjectivity of the inspector, there is a drawback that the test results are likely to vary. Therefore, an inspection apparatus capable of automatically measuring and evaluating is required.

Until now, several proposals have been made for automatic measurement and evaluation of abnormal sounds (for example, see Patent Document 1).
JP 2000-214052 (FIGS. 2 and 3)

Patent document 1 is demonstrated based on the following figure.
FIG. 9 is a diagram for explaining the principle of a conventional sound inspection apparatus. As shown in FIG. 9A, an omnidirectional microphone 102 and a unidirectional microphone beside a noise generation source 101 in a production plant 100. 103 is arranged. Information on the microphones 102 and 103 is sent to the noise waveform analyzer 104.
That is, the omnidirectional microphone 102 is installed for measuring background noise, and the unidirectional microphone 103 is installed for measuring sound generated by the noise source 101.

  In the noise waveform analyzer 104, the sound information collected by the omnidirectional microphone 102 is subjected to frequency analysis by the FFT analyzer 105 and stored in the first memory 106, as shown in FIG. Note that FFT means fast Fourier analysis. The sound information collected by the unidirectional microphone 103 is subjected to frequency analysis by the wavelet analyzer 107 and stored in the second memory 108. The measurement controller 109 calculates the true noise (frequency) of the noise source 101 excluding background noise from the frequency stored in the first memory 106 and the frequency stored in the second memory 108.

  The noise (frequency) generated by the noise generation source 101 is given by a time-frequency graph in which the horizontal axis is time and the vertical axis is frequency. Since the noise generation source 101 in the production plant 100 is to be monitored, the time is long, such as hours, days, and months.

On the other hand, the time given to the completed vehicle inspection at the vehicle factory is several tens of seconds to several minutes.
Therefore, the noise waveform analyzer 104 cannot be applied to a completed vehicle inspection.
Therefore, an inspection apparatus capable of performing sound / vibration inspection within a short time given for completed vehicle inspection or the like is required.

  It is an object of the present invention to provide a vehicle inspection apparatus capable of performing sound / vibration inspection in a short time.

The invention according to claim 1 is a vehicle inspection device that is placed in a running vehicle and inspects for sound or vibration reaching the vehicle,
The vehicle inspection apparatus is detachably connected to the vehicle-mounted ECU, and includes a terminal that takes in information including vehicle information related to the vehicle, a high-speed arithmetic processing medium that is removably inserted into the terminal, and the high-speed arithmetic processing medium. It consists of a microphone that sends sound information or a vibration sensor that sends vibration information.
The high-speed arithmetic processing medium includes a sound input terminal that takes in the sound information or a vibration input terminal that takes in the vibration information, and an input terminal such as a vehicle speed that takes in vehicle speed or engine speed information. Stores the specified sound threshold or vibration threshold, and has the function of selecting the sound threshold or vibration threshold based on the vehicle information taken in via the terminal. A fast Fourier transform circuit that creates a waveform diagram with the vertical axis as the vertical axis, and a function of adding the threshold value to the waveform diagram created by this circuit and calculating the area of the waveform diagram in a region exceeding the threshold value And
The high-speed arithmetic processing medium is a card that can be inserted into and removed from the terminal, and includes a terminal portion on one side of the four sides of the card,
This terminal portion consists of the sound input terminal, the vibration input terminal and the vehicle speed input terminal,
The terminal has a function of determining pass / fail based on an area calculated by the high-speed arithmetic processing medium.

  The invention according to claim 2 is characterized in that the terminal is a line end tester used for vehicle inspection.

  The invention according to claim 3 is characterized in that the high-speed arithmetic processing medium is a card conforming to PCMCIA type II.

  The invention according to claim 4 is characterized in that a hard logic circuit called a field programmable gate array is implanted in advance in a high-speed arithmetic processing medium together with a fast Fourier transform circuit.

  In the invention according to claim 1, the vehicle inspection device is configured by the terminal, the high-speed arithmetic processing medium, and the microphone or the vibration sensor. Then, a fast Fourier transform circuit is built in the high-speed arithmetic processing medium, and a correlation waveform diagram between the vehicle speed and sound or vibration is generated by this fast Fourier transform circuit. Further, the area of a part of the waveform diagram is calculated using a high-speed arithmetic processing medium. The terminal performs pass / fail determination based on the area.

The high-speed calculation processing medium has a calculation capability and a calculation speed capable of generating a correlation waveform diagram and calculating the area of the waveform diagram following the driving of the vehicle. That is, it has a real-time tracking function. Therefore, it is possible to make a pass / fail determination for sound or vibration at the end of the test run for several minutes. In the terminal, only simple pass / fail judgment is performed, and complicated calculation is not performed.
Therefore, according to the first aspect, it is possible to provide a vehicle inspection apparatus capable of performing sound / vibration inspection in a short time such as inspection running.

  Since the pass / fail of the inspection is found at the end of the inspection travel, the defect information can be quickly fed back to the assembly line, and measures can be taken early.

In addition, since the inspection apparatus includes a terminal, a high-speed arithmetic processing medium, and a microphone or a vibration sensor, the inspection apparatus is small and lightweight, can be easily carried into and out of the vehicle, and can efficiently inspect the vehicle.
In addition, since the inspection determination does not depend on human sensuality, there is no human variation and the determination reliability is increased.

The invention according to claim 2 is characterized in that the terminal is a line end tester used for vehicle inspection.
In the terminal, only simple pass / fail judgment is performed, and complicated calculation is not performed. Therefore, the line end tester that is always available at the inspection site can be used for the terminal. If the tester can be diverted, the vehicle inspection device will be inexpensive.

The invention according to claim 3 is characterized in that the high-speed arithmetic processing medium is a card conforming to PCMCIA type II.
PCMCIA type II is versatile and can be attached to a personal computer. As a result, a personal computer can be used as the terminal.

  In the invention according to claim 4, a hard logic circuit called a field programmable gate array is implanted in advance in the high-speed arithmetic processing medium together with the fast Fourier transform circuit. Since the hard logic circuit including the fast Fourier transform circuit can be made into one chip and is housed in a high-speed arithmetic processing medium, the handling of these circuits becomes extremely easy.

The best mode for carrying out the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a configuration diagram of a vehicle inspection apparatus according to the present invention. A vehicle inspection apparatus 10 is an apparatus that is placed in a running or idling vehicle and inspects sound or vibration that reaches the inside of the vehicle. (Engine control unit) 11 is detachably connected to a terminal 13 for taking in information including vehicle information relating to the vehicle 12, a high-speed arithmetic processing medium 14 to be detachably inserted into the terminal 13, and the high speed It consists of a microphone 15 for sending sound information to the arithmetic processing medium 14 or a vibration sensor for sending vibration information.

  The high-speed arithmetic processing medium 14 is preferably a PC card or a USB standard medium, but it does not matter.

The terminal 13 is placed in the passenger seat 16. The terminal 13 is connected to the vehicle-mounted ECU 11 by the first cable 17. The microphone 15 is disposed in the vicinity of the ear of the driver 19 sitting in the driver's seat 18. For this purpose, the microphone 15 may be temporarily fixed to the headrest 22 or the seat back 23 with an appropriate stay 21.
The microphone 15 is connected to the high-speed arithmetic processing medium 14 by the second cable 24.

FIG. 2 is an external view of a high-speed arithmetic processing medium and a terminal. The high-speed arithmetic processing medium 14 is preferably an IC card whose main part can be inserted into a personal computer, particularly PCMCIA type II or PCMCIA type III.
PCMCIA type II or PCMCIA type III is a card of business card size (54 mm × 84 mm). Type II is standardized to a thickness of 5 mm, and type III is standardized to a thickness of 10.5 mm.

  The high-speed arithmetic processing medium 14 includes a terminal portion 25 at one end. The terminal portion 25 has a sound input terminal 26 that is an insertion port of the second cable 24, a vibration input terminal 27 that is an insertion port of a cable extending from the vibration sensor, and An input terminal 29 such as a vehicle speed that is an insertion port of the branch harness 28 branched from the first cable 17 is provided. In addition to the vehicle speed and the engine rotation speed, a transmission shaft rotation speed may be taken in from the vehicle speed input terminal 29. In this case, the vehicle speed, the engine rotation speed, and the transmission shaft rotation speed are inspection items.

  Furthermore, the high-speed arithmetic processing medium 14 (the internal block diagram will be described later) stores a sound threshold or a vibration threshold predetermined for each vehicle, and is based on vehicle information taken in via a terminal. And a function for selecting a sound threshold or a vibration threshold, and a fast Fourier transform circuit 31 for creating a waveform diagram with the vehicle speed or engine speed as the horizontal axis and the sound or vibration as the vertical axis. A function is provided for adding a threshold value to the waveform diagram and calculating the area of the waveform diagram in a region exceeding the threshold value.

On the other hand, the terminal 13 can be a line end tester (hereinafter referred to as LET) used for inspection of personal computers and vehicles.
The LET will be described as an example. The terminal 13 is a portable type including a housing 33, a grip 34, keys 35, a display 36, a high-speed arithmetic processing medium throttle 37, and an insertion port 38 of the first cable 17 at a lower part. It is a tester.

  FIG. 3 is a block diagram of the high-speed arithmetic processing medium according to the present invention. The high-speed arithmetic processing medium 14 stores either sound information acquired from the sound input terminal 26 or vibration information acquired from the vibration input terminal 27. The switching unit 41 to be selected, the amplifier 42 that amplifies the selected signal, the low-pass filter 43 that processes the signal, the AD converter 44 that converts the signal, and the vehicle speed taken in from the input terminal 29 such as the vehicle speed An input correction circuit 45 that corrects information, an input correction circuit 46 that corrects engine speed information taken from the vehicle speed input terminal 29B indicated by an imaginary line, a one-chip hard logic circuit 47, and the hard logic circuit 47 and an interface unit 48 that plays a role of exchanging information with the outside (terminal 13, FIG. 2).

  The hard logic circuit 47 is a field programmable gate array (FPGA), and includes a fast Fourier transform circuit 31. That is, the hard logic circuit 47 and the fast Fourier transform circuit 31 are transplanted to the high-speed arithmetic processing medium 14 in advance. The hard logic circuit 47 including the fast Fourier transform circuit 31 has a content that fits in one chip. For this reason, tracking calculation can be performed once every several ms.

Next, the operation of the vehicle inspection apparatus having the above configuration will be described.
First, how to determine the threshold will be described.
FIG. 4 is a waveform diagram obtained in a certain run, where the horizontal axis indicates the vehicle speed and the vertical axis indicates sound (sound pressure level). It is shown that the sound increases as the vehicle speed increases. Much of the sound is emitted from the engine during acceleration. From the peak Pmax to the end of the measurement, the curve is lowered because the accelerator depression is weakened and the vehicle shifts to constant speed.

  In the range from the start of measurement to the end of measurement, the sound Pa at the start of measurement is almost minimum. Therefore, this Pa is defined as a “threshold value”. However, in order to increase the reliability of the value, it is desirable to prepare a plurality of vehicles for one vehicle type, obtain Pa for each, and determine the threshold value Pb from these average values.

Next, the peak evaluation method and the area evaluation method will be described.
FIG. 5 is a waveform diagram in which a threshold value is added. The threshold value Pb is added to the waveform diagram in FIG. Then, the area of the portion within the measurement range and above the threshold value Pb is obtained. This area is defined as Sact. Further, the height (height difference) from the threshold value Pb to the peak Pmax is defined as the peak value Pact.

Next, a driver and a plurality of (m) inspectors ride on the vehicle to be measured, perform a test run, acquire a waveform diagram, and cause the inspector to perform sensory evaluation.
The sensory evaluation gives a high score if comfortable, and a low score if uncomfortable. For example, the full score is 10 points, and if it is 6 points or more, it is accepted, and if it is 5 points or less, it is rejected.

  In one run, one Sact, one Pact, and a plurality (m) of sensory evaluation points are obtained. When traveling n times by changing the vehicle type or changing the vehicle, n Sact, n Pact, and (n × m) sensory evaluation points are obtained. A correlation diagram can be created with the sensory evaluation value on the horizontal axis and the Sact or Pact on the vertical axis. An example of such a correlation diagram is shown below.

FIG. 6 is a diagram showing the correlation between the sensory evaluation point, the peak value, and the area. As shown in (a), when the peak value Pact was plotted, it was dispersed in a wide band shape. The width of this band was “0.65” on the horizontal scale.
Moreover, as shown in (b), when the area Sact was plotted, it was dispersed in a narrow band shape. The width of this band was “0.41” on the horizontal scale.

From (a) and (b), the following was found.
When evaluating with the area Sact of (b), the individual difference remains “0.41”, but when evaluating with the peak value Pact of (a), the individual difference becomes “0.65”. When the pass / fail judgment is made, it is required that the individual difference is small. Therefore, it can be said that the area evaluation is more reliable than the peak value evaluation.
Therefore, in the present invention, the pass / fail judgment is basically performed with the area Sact and supplementarily with the peak value Pact.

Next, how to determine the allowable sound area value Salw and the allowable sound peak value Palw will be described.
Description will be made by regarding (a) and (b) as models. If the desired sensory evaluation value is 6.5, a thin line is drawn from 6.5 on the horizontal axis of (a), folded back from the center of the band to the left, and the point intersected with the vertical axis is the allowable peak value Palw of the sound. And
Similarly, a thin line is drawn from 6.5 on the horizontal axis of (b), turned back to the left from the center of the band, and a point crossing the vertical axis is set as an allowable sound area value Salw.

  In the above manner, data is accumulated and the following table is created.

  The vehicle A has models of 1300 cc, 1500 cc, and 1800 cc, and threshold values Pb1 to Pb3, sound allowable area values Salw1 to Salw3, and sound allowable peak values Palw1 to Palw3 are set for each of them.

Similarly, the vehicle B has 1000 cc and 1300 cc mounted models, and threshold values Pb4 to Pb5, sound allowable area values Salw4 to Salw5, and sound allowable peak values Palw4 to Palw5 are set for each of them.
Thus, the sound allowable area value Salw and the sound allowable peak value Palw can be selected from Table 1 if the vehicle is determined.

  The threshold value is stored in the high-speed calculation processing medium, and the sound allowable area value and the sound allowable peak value are stored in the terminal. After completing the above procedures, the following flow is executed.

FIG. 7 is a flowchart showing the procedure of the vehicle inspection according to the present invention. Note that the high-speed arithmetic processing medium is represented as a PC card in the figure.
First, at step number (hereinafter abbreviated as ST) 01, a high-speed arithmetic processing medium is inserted into the LET (terminal). This LET is connected to the in-vehicle ECU and acquires vehicle information (ST02). That is, the vehicle-mounted ECU has information unique to the vehicle.

  The high-speed arithmetic processing medium stores a vehicle detailed report-threshold correlation shown in Table 1. When the vehicle information (for example, vehicle A + 1500 cc) is acquired from the LET (ST03), the high-speed arithmetic processing medium selects a threshold (for example, Pb2) for each model based on Table 1 (ST04). Similarly, the LET stores a vehicle detail report-allowable area value and allowable peak value correlation shown in Table 1. LET selects an allowable area value (for example, Salw2) and an allowable peak value (for example, Palaw2) based on the vehicle information (for example, vehicle A + 1500cc) and Table 1 (ST05). The above ST03 to ST05 are executed immediately after ST02 is executed, and there is no order of superiority or inferiority in ST03 to ST05.

  Next, the microphone line and the vehicle speed line (FIG. 2, reference numerals 24 and 28) are connected to the high-speed arithmetic processing medium (ST06). Now that the preparation for the inspection is completed, the vehicle starts to travel (ST07). When the vehicle speed reaches the inspection start speed, real-time tracking is started (ST08). Specifically, using a fast Fourier transform circuit built in the high-speed arithmetic processing medium, a waveform diagram with speed as the horizontal axis and sound as the vertical axis is created, and the area Sact above the threshold is accumulated. Calculate (ST09).

  When tracking is completed due to reaching the maximum measurement speed (ST10), first, it is checked whether or not the area act is equal to or less than the allowable area value Salwx (Salw2 in this example) (ST11). If the area act is equal to or smaller than the allowable area value Salwx, “pass” is displayed on the display (FIG. 2, reference numeral 36) (ST12).

  If not, the peak value Pact is specified by the high-speed arithmetic processing medium (ST13). Then, it is checked whether or not the peak value Pact is equal to or less than the allowable peak value Palwx (Palw2 in this example) (ST14). If not, “fail” is displayed (ST15). In other words, if both the area and the peak value exceed the allowable value, the test is rejected.

  Although the area exceeds the allowable value, when the peak value is less than the allowable value, there is a possibility that the area can be reduced to the allowable value or less by performing fine adjustment. Therefore, in this case, “hold” is displayed (ST16).

  When the process is simplified, ST13, ST14, and ST16 are omitted, and NO in ST11 is directly connected to ST15. If it does so, a pass / fail judgment will be made more easily and an inspection will become simple.

  As described above, it is possible to inspect the sound and vibration of the vehicle without depending on the sensory inspection. In addition, this inspection does not require a large analyzer, and only requires a high-speed arithmetic processing medium and a LET or personal computer that are easily available.

  FIG. 8 is a diagram showing another embodiment of FIG. 2. The terminal 13 is a personal computer, and the high-speed arithmetic processing medium 14 may be inserted into the high-speed arithmetic processing medium throttle 37 of this personal computer. The rest of the configuration is the same as that in FIG.

  The vehicle inspection apparatus of the present invention is preferably installed in an inspection site that inspects the sound and vibration of a completed vehicle, but can also be installed in a vehicle inspection site, a vehicle repair site, or a dealer. And uses are free.

  The vehicle inspection apparatus of the present invention is desirably provided at the end of the assembly line of the vehicle manufacturer.

It is a block diagram of the vehicle inspection apparatus which concerns on this invention. It is an external view of a high-speed arithmetic processing medium and a terminal. It is. It is a wave form diagram obtained by a certain run. It is a wave form diagram which added the threshold value. It is a figure which shows the correlation with a sensory evaluation point, a peak value, and an area. It is a flowchart which shows the procedure of the vehicle inspection which concerns on this invention. It is a figure which shows another Example of FIG. It is a figure explaining the principle of the conventional sound inspection apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Vehicle inspection apparatus, 11 ... In-vehicle ECU (engine control unit), 12 ... Vehicle, 13 ... Terminal, 14 ... High-speed arithmetic processing medium, 15 ... Microphone, 26 ... Sound input terminal, 27 ... Vibration input terminal, 29 ... Vehicle speed input terminal, 31 ... Fast Fourier transform circuit.

Claims (4)

A vehicle inspection device that is placed in a running or idling vehicle and inspects for sound or vibration reaching the vehicle,
The vehicle inspection apparatus is detachably connected to the vehicle-mounted ECU, and includes a terminal that takes in information including vehicle information related to the vehicle, a high-speed arithmetic processing medium that is removably inserted into the terminal, and the high-speed arithmetic processing medium. It consists of a microphone that sends sound information or a vibration sensor that sends vibration information.
The high-speed arithmetic processing medium includes a sound input terminal that takes in the sound information or a vibration input terminal that takes in the vibration information, and an input terminal such as a vehicle speed that takes in vehicle speed or engine speed information. Stores the specified sound threshold or vibration threshold, and has the function of selecting the sound threshold or vibration threshold based on the vehicle information taken in via the terminal. A fast Fourier transform circuit that creates a waveform diagram with the vertical axis as the vertical axis, and a function of adding the threshold value to the waveform diagram created by this circuit and calculating the area of the waveform diagram in a region exceeding the threshold value And
The high-speed arithmetic processing medium is a card that can be inserted into and removed from the terminal, and includes a terminal portion on one side of the four sides of the card,
This terminal portion consists of the sound input terminal, the vibration input terminal and the vehicle speed input terminal,
The vehicle inspection apparatus, wherein the terminal has a function of determining pass / fail based on an area calculated by the high-speed arithmetic processing medium.   2. The vehicle inspection apparatus according to claim 1, wherein the terminal is a line end tester used for vehicle inspection.   3. The vehicle inspection apparatus according to claim 1, wherein the high-speed arithmetic processing medium is a card conforming to PCMCIA type II.   4. A hard logic circuit called a field programmable gate array is preliminarily implanted in the high-speed arithmetic processing medium together with the fast Fourier transform circuit. Vehicle inspection equipment.

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