Vehicle inspection and display method and device

Abstract

To specify a component type and vehicle type being a sounding source and display them together with the sound normality / abnormality determination result in a step of performing a plurality of inspections based on the sound.SOLUTION: An inspection display method collects the sound from a vehicle which is going on a trial run on a free roller to acquire the sound as sound data (S1), calculates the sound pressure characteristics and frequency characteristics of the acquired sound (S2), specifies a component type being a sounding source on the basis of the sound pressure characteristics and frequency characteristics (S3), specifies a vehicle type by using the characteristics of the different sounds for each vehicle type predicated on the specified component type (S4), determines whether or not the component sound is the normal sound or abnormal sound predicated on the specified component type and specified vehicle type (S5), generates images of the sound data and frequency data (S6), and displays the images, the specified component and vehicle type and the determination result on the normal sound or abnormal sound on a display (S7).SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a method and apparatus for displaying the results of an inspection of a vehicle such as an automobile, to determine whether or not the sound emitted from a part being inspected is abnormal. [Background technology]

[0002] For example, in the final stage of an automobile production line, in the finished vehicle inspection process, inspectors test drive the finished vehicle on free rollers and inspect numerous items, including the engine, meters, brakes, horn, and lights. Generally, during this inspection process, the presence or absence of abnormalities is determined by the inspector's sensory evaluation of various sounds emitted from various parts of the vehicle. For example, in the case of a horn, the inspector sounds the horn and listens to it to confirm that it is normal. Sounds emitted from the transmission during acceleration and from the brakes during braking are also subject to sensory inspection.

[0003] Instead of such sensory testing, attempts have been made to detect abnormalities by capturing sounds emitted by a test object with a microphone and analyzing the signals. For example, Patent Document 1 discloses a technology in which abnormal sounds from a sliding part such as a film shutter at the air outlet of a car air conditioner are tested, and abnormal sounds are judged based on the product of the sound pressure and duration of the abnormal sound (time integral value of the sound pressure value) while removing disturbance noise. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 4134943 Summary of the Invention [Problem to be solved by the invention]

[0005] For example, in the above-mentioned finished vehicle inspection process, inspections are sequentially performed on multiple parts that emit some kind of sound, and sometimes one part is operating while another part is operating for inspection. In Patent Document 1, when multiple inspection targets are mixed together like this, no attempt is made to identify which part the acquired sound belongs to. Furthermore, no consideration is given to using the acquired sound to identify the vehicle model. [Means for solving the problem]

[0006] The vehicle inspection and display method according to the present invention comprises: During the finished vehicle inspection process on the automobile production line, Acquire the sound emitted from the vehicle to be inspected, The acquired sound is analyzed to identify the type of component that is the source of the acquired sound, Identifying the vehicle model to be inspected based on the characteristics of the part sounds that differ for each vehicle model among the identified part types; Obtain vehicle information corresponding to the vehicle identification number of the vehicle being inspected, The vehicle model identified from the part sound is compared with the vehicle model based on the vehicle information to determine whether they are the same vehicle model; If it's the same model, Determine whether the analyzed part sounds contain abnormal sounds, Displays part type, vehicle model, and whether or not there is an abnormal sound death, If the vehicle model does not match, it will not determine whether an abnormal sound is present, but will display the part type, the vehicle model identified from the part sound, and the fact that the vehicle model is different. do. [Effects of the Invention]

[0007] According to this invention, since the part type is identified first, the vehicle model is identified and abnormal sound judgment is made within the specific part type, and even if multiple part sounds are mixed or occur in an unspecified order, the vehicle model can be identified and abnormal sound judgment can be made with high accuracy.Furthermore, by displaying the part type, vehicle model, and whether or not abnormal sound is present, the efficiency of the inspection is improved. In addition, the vehicle model identified from the part sound is compared with the vehicle model in the vehicle information, and if the vehicle models do not match, a message to that effect is displayed, so that it is possible to correctly determine whether the sound is abnormal, assuming that there is no mistake in the specifications of the horn, etc. [Brief explanation of the drawings]

[0008] [Figure 1]FIG. 1 is a functional block diagram of a first embodiment in which the present invention is applied to an abnormal noise inspection in a finished automobile vehicle inspection process. [Figure 2] 4 is a flowchart showing the flow of processing in the first embodiment. [Figure 3] FIG. 3 is an explanatory diagram showing a display example on the display unit of the first embodiment. [Figure 4] FIG. 10 is a functional block diagram of a second embodiment. [Figure 5] 10 is a flowchart showing the flow of processing in a second embodiment. [Figure 6] FIG. 10 is an explanatory diagram showing a display example on a display unit according to a second embodiment. [Figure 7] FIG. 10 is an explanatory diagram showing a display example when the vehicle types do not match. [Figure 8] FIG. 10 is a functional block diagram of a third embodiment. [Figure 9] 10 is a flowchart showing the flow of processing according to a third embodiment. [Figure 10] FIG. 11 is an explanatory diagram showing an example of display of statistical processing data on a display unit according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] An embodiment of the present invention applied to an abnormal noise inspection in a finished vehicle inspection process for automobiles will be described below. Generally, in the finished vehicle inspection process, which is the final stage of an automobile production line, an inspector test-drives the finished vehicle to be inspected on free rollers, inspecting numerous items including the engine, transmission, meters, horn, brakes, etc., in a predetermined inspection sequence. The inspection display device of this embodiment acquires sounds from the vehicle without relying on timing signals from the vehicle, and uses the acquired sounds to identify the part type, the vehicle model, and determine whether or not an abnormal sound (also called an abnormal noise) is present, and displays the results.

[0010] In one embodiment, the component types that are sound sources (i.e., component types that are the subject of inspection) include, for example, a horn, an engine, a transmission, and a brake. For the horn, an inspector sounds the horn by pressing a horn switch on the steering wheel, and based on the sound, it is determined whether the horn is normal. Furthermore, while the inspector accelerates by depressing the accelerator pedal until the vehicle reaches a predetermined speed, it is determined whether the engine and transmission sounds contain any abnormal sounds. For the brakes, it is inspected whether any abnormal sounds are generated when the inspector depresses the brake pedal to activate the brakes.

[0011] 1 shows a functional block diagram of the inspection display device of Example 1. The inspection display device of Example 1 is configured to include a sound acquisition unit 10, a frequency characteristic analysis unit 20, a part identification unit 30, a vehicle model identification unit 40, an abnormal sound determination data storage unit 50, a normal sound / abnormal sound determination unit 60, a display image / video generation unit 70, and a display unit 80.

[0012] The sound acquisition unit 10 includes a microphone that acquires sounds generated from the vehicle under inspection and converts them into electrical signals, i.e., sound data, and a recording unit that temporarily stores this sound data. The microphone is placed outside the vehicle so that it can collect sounds from the vehicle, including sounds from the horn, brakes, etc. The directivity and frequency characteristics of the microphone are selected according to the measurement target. Typically, a microphone with directivity toward the vehicle is used. It is also possible to obtain sound data from which noise sounds have been removed by localizing the sound source using a microphone array or the like. Note that if the sound source can be localized using a microphone array, the sound source position can also be used as one element for identifying the part type.

[0013] The frequency characteristic analysis unit 20 performs a frequency analysis of the acquired sound data, for example, by using a frequency analysis method such as FFT (Fast Fourier Transform) or wavelet analysis to convert the data according to frequency, thereby generating frequency data.

[0014] When frequency data is expressed in two dimensions, for example, it is expressed as a frequency spectrum with frequency on the horizontal axis and power (or sound pressure) on the vertical axis. Note that the vertical axis of the frequency spectrum is not limited to power and sound pressure, and other parameters may be used, such as a value obtained by multiplying the A-characteristic function of hearing or loudness, which is a sensory quantity of hearing defined by ISO. Furthermore, by superimposing the conversion results for each time in a time series, the frequency data may be handled as a so-called spectrogram, which is three-dimensional data including time.

[0015] The component identification unit 30 identifies the component type that is the source of the sound based on the time band characteristics of the acquired sound data and the characteristics of the frequency data (such as a frequency spectrum or spectrogram) obtained by the frequency characteristic analysis unit 20. That is, the component identification unit 30 identifies the component type that is the source of the sound by comparing at least one of the sound pressure, time characteristics, and frequency characteristics of the acquired sound with the characteristics of multiple component types (for example, horn, engine, transmission, brake) that are prepared in advance as inspection items.

[0016] For example, the sound pressure, frequency characteristics, and time characteristics (such as the rise of sound pressure and the duration of sound) of sounds emitted by each type of part differ, and these can be used as clues to determine which type of part the sound comes from. As a specific example, the sound pressure range of the sound emitted by an automobile horn is regulated by law, and the shape of the time-sound pressure waveform is also characteristic. Furthermore, engine sounds can be identified by the fact that the frequency band of the sound is mainly composed of a fundamental frequency and harmonic frequencies corresponding to the engine rotation speed (rpm), and by the sound pressure and frequency range for that engine rotation speed. Brake sounds and transmission sounds can also be identified in a similar manner by comparing spectrograms, for example.

[0017] The vehicle model identification unit 40 identifies the vehicle model of the vehicle being inspected based on the characteristics of the part sounds that differ for each vehicle model among the identified part types. That is, assuming that the sound is from a specific part type, the vehicle model is identified using, for example, the time band characteristics of the sound data acquired by the part identification unit 30, the frequency characteristics obtained by frequency analysis, and even more detailed spectrograms, mel-cepstrum, etc.

[0018] For example, taking horns as an example, it is common for different models of horns to be used for each vehicle model (e.g., vehicle model A, vehicle model B, vehicle model C, etc.), and even for horns of the same model, the sound changes depending on the parts layout, etc., so the horn sound will differ slightly for each vehicle model. Therefore, for example, by taking advantage of the fact that the frequency of maximum sound pressure differs depending on the vehicle model, it is possible to identify the vehicle model by identifying vehicle model A for maximum sound pressure frequencies (Hz) in the range of f1 to f2, vehicle model B for maximum sound pressure frequencies in the range of f3 to f4, etc.

[0019] In the case of engine sounds, transmission sounds, and brake sounds, spectrogram images are learned, image features (such as the spacing, length, and slope of light and dark lines) are extracted, and from these features it is possible to identify vehicle model A, vehicle model B, etc. For example, even if the engine is the same model, the sound can differ depending on the vehicle model it is installed in.

[0020] Alternatively, a Mel-cepstrum method that takes into account the transfer characteristics of the vocal tract and is widely used for speaker identification may be used to define features for each vehicle type and identify the vehicle type.

[0021] When identifying this vehicle model, the type of part that is the source of the sound has already been identified, so it is possible to analyze and compare in detail the characteristics of sounds within the same part type, making vehicle model identification relatively easy and highly accurate.

[0022] The abnormal sound determination data storage unit 50 is made up of a database that stores the basic characteristics of sounds determined to be normal for each of the above-mentioned component types and for each individual component. For example, the database stores sound data or frequency data (such as frequency spectra and spectrograms) of normal sounds, or data on characteristic portions of the sound data or frequency data for distinguishing between normal and abnormal sounds.

[0023] The normal sound / abnormal sound determination unit 60 compares the characteristics of the component sound acquired this time with the data in the abnormal sound determination data storage unit 50 to determine whether an abnormal sound is included.

[0024] For example, in the case of a horn, if the vehicle model is identified as vehicle model A, the sound pressure range of the acquired sound is compared with the sound pressure range of a normal horn for vehicle model A stored in abnormal sound determination data storage unit 50, and whether the sound is normal or abnormal is determined based on the difference, similarity, etc. between the two. For example, a statistical method using the average value, variance, etc., or a method of vectorizing the sound and setting a threshold value using the cosine similarity, which is the angle between the vectors, and quantitatively determining whether the sound is normal or abnormal based on whether it is larger or smaller than the threshold value can be used.

[0025] In the case of frequency characteristics, multiple combinations of frequency and sound pressure at which peak frequencies, which are characteristic of the sound, appear are extracted, and by comparing these with the data stored in the abnormal sound detection data storage unit 50, it is possible to distinguish between normal and abnormal sounds.

[0026] In the case of engine sounds, for example, a spectrogram of the currently acquired part sound identified as vehicle type A is generated, and the drawn image is compared with drawn images of spectrograms of normal vehicle type A stored in abnormal sound determination data storage unit 50, and normal and abnormal sounds are distinguished from each other based on differences or similarities in the feature amounts of the images (for example, the spacing, length, and inclination of light and dark lines). In other words, normal and abnormal sounds are distinguished by learning a large number of drawn images of spectrograms of normal part sounds for each vehicle type.

[0027] The normal sound / abnormal sound determining unit 60 is not limited to the above example, and any known appropriate method for distinguishing between normal and abnormal sounds can be used.

[0028] When determining whether a sound is normal or abnormal, the type of part that is the source of the sound and the vehicle model are already identified, so it is possible to analyze and compare in detail the sound characteristics of specific parts, making it easy to make a highly accurate determination.

[0029] The display image / video generation unit 70 generates images or videos to be displayed on the display unit 80, including the results obtained as described above (identified part type, identified vehicle model, normal / abnormal sound), as well as the processing steps leading up to the results. The display unit 80 is a display means for displaying the generated images or videos to relevant parties, such as the inspector driving the vehicle, the production manager, and the data scientist who utilizes the data. For example, the display unit 80 may be configured with an LCD display, an organic light-emitting diode (OLED) display, a head-mounted display (HMD), a smartwatch, or the like. In addition, if audio is involved, the display unit 80 may also include a sound source, amplifier, speaker, and the like for generating and emitting sound. The display image / video generation unit 70 generates various displays, such as still images, videos, and animations, and performs splitting, compositing, and switching between them to provide appropriate displays. Display timing control also enables different displays to be displayed on multiple display units 80 at appropriate times.

[0030] FIG. 3 is an explanatory diagram showing an example of a display on the display unit 80 of the first embodiment. In this example, four items are displayed on the display screen, from top to bottom: "(1) Sound pressure / frequency characteristics," "(2) Name of component of target sound," "(3) Name of vehicle model of target sound," and "(4) Normal / abnormal judgment result of target sound." To the right of the "(1) Sound pressure / frequency characteristics" item, a two-dimensional graph of sound data (see reference numeral 80a) with sound pressure on the vertical axis and time on the horizontal axis as the "sound pressure characteristics" and a frequency spectrum (see reference numeral 80b) with power on the vertical axis and frequency on the horizontal axis as the "frequency characteristics" are shown. The box to the right of "(2) Name of component of target sound" (see reference numeral 80c) displays the identified component type, in this example, "horn sound," and the box to the right of "(3) Name of vehicle model of target sound" (see reference numeral 80d) displays the identified vehicle model name (assuming vehicle model B in this example). Furthermore, the box to the right of "(4) Normal / Abnormal Judgment Result of Target Sound" (see symbol 80e) displays the normal / abnormal judgment result, in this example, the word "normal sound." Depending on the type of component, a spectrogram including a time axis or the like may be displayed in the "Frequency Characteristics" box 80b.

[0031] Based on such displays, inspectors can easily know which part's sound was inspected during the finished vehicle inspection process, which involves various inspections, which model of vehicle the sound was identified as belonging to, and whether the part in question is normal.

[0032] 2 is a flowchart showing the processing flow of the inspection display device of the first embodiment. First, the microphone of the sound acquisition unit 10 collects sounds, including horn sounds, from a vehicle running on a free roller and acquires them as sound data (Step 1). Next, the sound pressure characteristics and frequency characteristics of the acquired sounds are calculated (Step 2).

[0033] In step 3, the part type that is the source of the noise is identified based on these sound pressure characteristics and frequency characteristics. In step 4, based on the identified part type, the vehicle model is identified using the sound characteristics that differ for each vehicle model of parts that belong to this part type.

[0034] In step 5, it is determined whether the part sound is normal or abnormal, based on the identified part type and the identified vehicle model.

[0035] In step 6, images of the sound data and frequency data are generated to be displayed on the screen as the "sound pressure characteristics" and "frequency characteristics" shown in Figure 3. Then, in step 7, these images, the identified parts and vehicle models, and the results of the normal / abnormal sound determination are displayed on the screen.

[0036] Finally, in step 8, it is determined whether the inspector has pressed the stop button to end the inspection. If the stop button has not been pressed after the inspection results have been displayed on the display, the processes of steps 1 to 7 are repeated. For example, if the display indicates that the horn sound is abnormal, the horn switch can be operated again to repeat the horn inspection. If the stop button is pressed, the inspection ends. When this inspection is complete, a message to that effect is displayed on the display that serves as the display unit 80. A buzzer or voice may be sounded to notify the end of the inspection along with the display.

[0037] Next, an inspection display device of a second embodiment will be described with reference to Figures 4 to 7. The following mainly describes the parts that differ from the first embodiment. The inspection display device of the second embodiment differs from the first embodiment in that it acquires vehicle information corresponding to the unique vehicle identification number of the vehicle being inspected from a factory production management system or the like, determines whether the vehicle model identified from the part sounds matches the vehicle model based on the vehicle information, and displays the result of the determination.

[0038] 4 shows a functional block diagram of the inspection display device of Example 2. Like the first example, the inspection display device of Example 2 includes a sound acquisition unit 10, a frequency characteristic analysis unit 20, a part identification unit 30, a vehicle type identification unit 40, an abnormal sound determination data storage unit 50, a normal sound / abnormal sound determination unit 60, a display image / video generation unit 70, and a display unit 80, and further includes a vehicle information acquisition unit 90 and a vehicle type comparison unit 100.

[0039] The vehicle information acquisition unit 90 acquires vehicle information including correct vehicle model information corresponding to the vehicle's unique chassis number. For example, the vehicle information acquisition unit 90 acquires vehicle information for vehicles currently undergoing the finished vehicle inspection process by communicating with a factory production management system via an in-house network or the like. Alternatively, information from an IC tag or three-dimensional barcode attached to the vehicle may be read during the finished vehicle inspection process. Alternatively, the vehicle currently undergoing inspection may be identified using a counter that counts the number of vehicles on the assembly line, and its vehicle information may be acquired.

[0040] The vehicle model comparison unit 100 compares the vehicle model identified by the vehicle model identification unit 40 based on the component sounds as described above with the vehicle model identified based on the vehicle information acquired by the vehicle information acquisition unit 90, and determines whether they are the same vehicle model. The comparison results, together with the names of the respective vehicle models, are output to the display image / video generation unit 70 and displayed on the display unit 80.

[0041] FIG. 6 is an explanatory diagram showing an example of a display on the display unit 80 of the second embodiment. In this example, five items are displayed on the display screen, from top to bottom: "(1) Sound pressure / frequency characteristics of sound," "(2) Name of component of target sound," "(3) Name of vehicle model of target sound: factory system," "(4) Name of vehicle model of target sound: identified from sound," and "(5) Normality / abnormality judgment result of target sound." To the right of the "(1) Sound pressure / frequency characteristics" item, a two-dimensional graph of sound data (see reference numeral 80a) with sound pressure on the vertical axis and time on the horizontal axis is shown as "sound pressure characteristics," and a frequency spectrum (see reference numeral 80b) with power on the vertical axis and frequency on the horizontal axis is shown as "frequency characteristics." A spectrogram or the like may also be displayed as "frequency characteristics." In a box (see reference numeral 80c) to the right of "(2) Name of component of target sound," the identified component type, in this example, "horn sound," is displayed. The box to the right of "(3) Model name of target sound: Factory system" (see symbol 80f) displays the model name (model B in this example) identified from the vehicle information, and the box to the right of "(4) Model name of target sound: Identified from sound" (see symbol 80g) displays the model name (model B in this example) identified from the part sound, just like in the first embodiment. Furthermore, a box to the right of these model name boxes 80f and 80g (see symbol 80h) displays the comparison result between the two, for example, with the text "Models match." The box to the right of "(5) Normality / Abnormality Judgment Result of Target Sound" (see symbol 80e) displays the normality / abnormality judgment result, in this example, the text "Abnormal sound," just like in the first embodiment.

[0042] FIG. 7 is an explanatory diagram showing a display example when the vehicle model identified based on the part sound does not match the vehicle model identified based on the vehicle information. In this example, the vehicle model identified from the vehicle information is "Vehicle model B," while the vehicle model identified from the part sound is "Vehicle model C." These vehicle model names are displayed in boxes 80f and 80g, respectively. Box 80h, which shows the comparison result, displays the message "Vehicle model is different. Please check the part specifications." In other words, if the identified vehicle models do not match, there is a possibility that different models of parts have been mistakenly installed on the assembly line. Therefore, a message is displayed that clearly indicates that the vehicle models are different and prompts the user to check for any incorrect part specifications. Furthermore, the box to the right of "(5) Normality / Abnormality Judgment Result of Target Sound" (see symbol 80e) displays the word "Undetermined." This indicates that, since the vehicle models do not match, the part sound will not be judged as normal or abnormal.

[0043] In this way, by identifying the vehicle model from the part sound and comparing it with the vehicle model in the vehicle information, it is possible to discover errors in the specifications of parts such as the horn.

[0044] 5 is a flowchart showing the processing flow of the inspection display device of the second embodiment. First, sound, including, for example, the sound of a horn, is collected by the microphone of the sound acquisition unit 10 from a vehicle test-running on free rollers and acquired as sound data (Step 1). Next, the sound pressure characteristics and frequency characteristics of the acquired sound are calculated (Step 2), and the part type that is the source of the sound is identified based on these sound pressure characteristics and frequency characteristics (Step 3). Then, based on the identified part type, the vehicle type is identified using the sound characteristics that differ for each vehicle model of parts belonging to this part type (Step 4).

[0045] Next, the process proceeds to step 11, where vehicle information is acquired from a factory system or the like, and the vehicle model is identified based on the vehicle information. Then, the process proceeds to step 12, where it is determined whether the two vehicle models are the same.

[0046] If the vehicle model is the same, proceed to step 5, and determine whether the part sound is normal or abnormal based on the identified part type and identified vehicle model, as in the first embodiment. Also, generate images of the sound data and frequency data (step 6), and display these images, the identified part, vehicle model, and the determination result of normal / abnormal sound on the display (step 7).

[0047] If the vehicle model is different, the process proceeds to step 13, where a display for a different vehicle model (see Figure 7) is generated. Then, from step 13, the process proceeds to step 6 without determining whether the sound is normal or abnormal (step 5), and an image of the sound data and frequency data is generated (step 6) and finally displayed (step 7).

[0048] Finally, in step 8, it is determined whether the inspector has pressed the stop button to end the inspection. If the stop button has not been pressed after the inspection results are displayed on the screen, the processes in steps 1 to 7 are repeated, and the inspection ends when the stop button is pressed.

[0049] Next, an inspection display device of a third embodiment will be described with reference to Figures 8 to 10. The inspection display device of the third embodiment is the inspection display device of the first embodiment, which further adds a function to perform statistical processing for at least the part type and vehicle model after data on vehicles in which abnormal sounds have been detected has been accumulated, and to display the results of this statistical processing in a graph.

[0050] 8 shows a functional block diagram of the inspection display device of Example 3. Like the first example, the inspection display device of Example 3 includes a sound acquisition unit 10, a frequency characteristic analysis unit 20, a part identification unit 30, a vehicle type identification unit 40, an abnormal sound determination data storage unit 50, a normal sound / abnormal sound determination unit 60, a display image / video generation unit 70, and a display unit 80, and further includes a vehicle information acquisition unit 90 and an abnormal state compilation / analysis unit 110.

[0051] The vehicle information acquisition unit 90 is similar to that in the second embodiment described above, and acquires vehicle information from a factory production management system or the like.

[0052] The abnormality status compilation and analysis unit 110 receives information on part type from the part identification unit 30, vehicle information from the vehicle information acquisition unit 90, and information from the normal sound / abnormal sound determination unit 60, and performs statistical processing on cases determined to be abnormal. For example, it collects abnormality samples by part type or by vehicle model, and extracts feature information that is highly correlated with the occurrence of an abnormality. For example, the vehicle information acquired from the vehicle information acquisition unit 90 includes production-related information such as specification values, manufacturing date and time, and the person in charge of manufacturing. Using this information, it is possible to extract feature information such as, for example, that abnormalities occur frequently during night shifts, or that they coincide with the timing of a switch in parts manufacturers.

[0053] In addition to the display image of the first embodiment described above, the display image / video generation unit 70 generates a display image showing the results of these statistical processes and feature information, and displays it on the display unit 80. For example, the statistically processed data is displayed by switching the display screen.

[0054] FIG. 10 is an explanatory diagram showing an example of statistically processed data displayed on a display. In this example, data summarized by vehicle model and part type is displayed in the form of a three-dimensional bar graph. Specifically, the x-axis of the three-dimensional bar graph represents vehicle model (in the illustrated example, vehicle model A, vehicle model B, vehicle model C, etc.), the y-axis represents part type (in the illustrated example, engine, brake, horn, etc.), and the z-axis represents the number of samples (number of abnormalities). Characteristic information extracted through statistical processing is displayed as text in speech bubbles attached to the bar graphs. For example, in the illustrated example, characteristic information such as "night shift: 80%" (see reference numeral 80j) and "due to change of parts manufacturer" (see reference numeral 80k) is added to the two bar graphs with the highest number of abnormalities. A button (see reference numeral 80m) for returning to the display shown in FIG. 3 is located at the bottom right of the screen. Touching this button 80m by an inspector or other personnel returns to the display shown in FIG. 3 (i.e., normal inspection).

[0055] By statistically processing and displaying the cases where abnormalities have been determined in this way, it is possible to easily grasp the tendency of abnormalities occurring for each part type or vehicle model, and it becomes easy to take subsequent measures.

[0056] 9 is a flowchart showing the processing flow of the inspection display device of the third embodiment, and particularly shows the processing of the statistical processing portion that is combined with the flowchart of FIG. 2. In the first step 21, it is determined whether analysis of abnormal data has been requested. For example, analysis may be performed when necessary by an inspector operating a switch, or analysis may be performed automatically each time a certain number of samples are accumulated. If the answer is YES, proceed to step 22 and beyond; if the answer is NO, return to the routine of FIG. 2 described above without performing statistical processing or analysis.

[0057] In step 22, the abnormality data accumulated up to that point is used to tally up abnormalities by part type, and in step 23, the abnormalities are similarly tally up by vehicle type. Then, in step 24, the above-mentioned characteristic information is extracted based on these tally up data.

[0058] In step 25, an image to be displayed on the display including the abnormality occurrence summary graph and the characteristic information is generated, and in step 26, it is displayed on the display.

[0059] In step 27, it is determined whether the above-mentioned button 80m on the screen has been pressed, and the statistical information continues to be displayed until this button 80m is pressed. If button 80m is pressed, the process returns to step 21, and finally returns to the normal inspection shown in Figure 2.

[0060] Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment and can be applied in various other ways. For example, the present invention can be used for inspection and maintenance in a repair shop. Furthermore, the inspection targets are not limited to the horn, engine, transmission, and brakes mentioned above, but can also include sounds from other parts that produce sound, alarms, notification sounds, etc. Furthermore, the inspection targets are not limited to sounds that are produced (or change in sound) based on active operation by the inspector, such as the horn or acceleration operation, but can also include sounds of parts that unexpectedly occur during inspection unrelated to operation.

[0061] Furthermore, in the above embodiment, the vehicle model is identified based on the part sound of one part type, but it is also possible to provisionally determine the vehicle model based on the part sounds of a plurality of part types, and then finally identify the vehicle model if the respective determination results match each other.

[0062] Furthermore, in the above embodiment, as illustrated in FIG. 3 etc., the part type, vehicle model, and whether or not there is an abnormal sound are displayed simultaneously, but in the present invention, it is not essential that these be displayed simultaneously, and they may be displayed sequentially by switching the screen, for example. [Explanation of symbols]

[0063] 10...Sound acquisition section 20...Frequency characteristic analysis section 30...Parts identification section 40...Vehicle identification section 50...Data storage unit for abnormal noise detection 60...Normal sound / abnormal sound determination section 70...Display image / video generation unit 80…Display section 90...Vehicle information acquisition unit 100...Vehicle comparison section 110...Abnormal condition collection and analysis unit

Claims

1. In the finished vehicle inspection process on an automobile production line, Acquire the sound emitted from the vehicle to be inspected, The acquired sound is analyzed to identify the type of component that is the source of the acquired sound, Identifying the vehicle model to be inspected based on the characteristics of the part sounds that differ for each vehicle model among the identified part types; Obtain vehicle information corresponding to the vehicle identification number of the vehicle being inspected, The vehicle model identified from the part sound is compared with the vehicle model based on the vehicle information to determine whether they are the same vehicle model; If it is the same model, it will determine whether the analyzed part sounds contain any abnormal sounds, The part type, vehicle model, and whether or not there is an abnormal sound are also displayed. If the vehicle model does not match, the system will not determine whether an abnormal sound is present, but will display the part type, the vehicle model identified from the part sound, and the fact that the vehicle model is different. How to display vehicle inspections.

2. When the vehicle model is different, a message will be displayed prompting you to check for incorrect part specifications. The vehicle inspection and display method according to claim 1.

3. To identify the above part types, Identifying the component type of the sound source by comparing at least one of the sound pressure, time characteristics, and frequency characteristics of the acquired sound with characteristics of multiple component types prepared in advance as inspection items; 3. The vehicle inspection and display method according to claim 1 or 2.

4. The above vehicle types are identified as follows:

4. The vehicle inspection and display method according to claim 1, wherein the vehicle type is identified by comparing the acquired spectrogram waveform of the part sound with spectrogram waveforms of part sounds for each vehicle type.

5. The above vehicle types are identified as follows:

4. The vehicle inspection and display method according to claim 1, wherein the vehicle type is identified by comparing the frequency of the maximum sound pressure of the acquired part sound with characteristics of each vehicle type.

6. 6. The vehicle inspection and display method according to claim 1, wherein at least two of the following parts are included in the inspection target as sound source part types: a horn, an engine, a transmission, and a brake.

7. After accumulating data on vehicles in which abnormal sounds have been detected, statistical processing is performed on at least the part type and vehicle model, and the results of this statistical processing are displayed in a graph. The vehicle inspection and display method according to any one of claims 1 to 6.

8. In the finished vehicle inspection process of an automobile production line, a sound acquisition unit that acquires sounds emitted from a vehicle to be inspected; a component identification unit that analyzes the acquired sound and identifies the component type that is the source of the acquired sound; a vehicle type identification unit that identifies the vehicle type of the vehicle being inspected based on the characteristics of the part sounds that differ for each vehicle type among the identified part types; a vehicle information acquisition unit that acquires vehicle information corresponding to the vehicle identification number of the vehicle to be inspected; a vehicle model comparison unit that compares the vehicle model identified from the part sound with the vehicle model based on the vehicle information to determine whether they are the same vehicle model; If the vehicle is the same model, an abnormal sound detection unit determines whether the analyzed part sounds contain abnormal sounds; a display unit that displays the part type, the vehicle model, and whether or not there is an abnormal sound if the vehicle models are the same, and that displays the part type, the vehicle model, and whether or not there is an abnormal sound if the vehicle models do not match, but displays the vehicle model identified from the part type and the part sound, and the fact that the vehicle models are different; A vehicle inspection and display device comprising:

Images