JP6191204B2 - Appearance inspection apparatus and appearance inspection method for automobile body - Google Patents

Description

  TECHNICAL FIELD The present invention relates to an automobile body appearance inspection apparatus and an appearance inspection method for performing a final appearance inspection of a produced automobile, and in particular, the appearance of fine scratches and the like on a painted surface, which is a vehicle body outer plate surface produced in an automobile production line. The present invention relates to an appearance inspection apparatus and an appearance inspection method for inspecting whether there is a defect.

  In many cases, the appearance inspection of automobiles produced in the automobile production line is performed as a visual inspection by human eyes, but as described in, for example, Patent Document 1 and Patent Document 2 as part of automatic inspection, There has been proposed an appearance (surface) inspection apparatus by image processing for the purpose of detecting an appearance defect (surface defect) site such as a fine scratch on a painted surface.

  In the appearance inspection technique described in Patent Document 1, an automobile body to be inspected is conveyed by a conveyor with respect to a camera that is a fixed-position imaging device, and the camera and the automobile body move relative to each other. As a result, the painted surface of the car body is imaged by the camera.

  In addition, in the appearance inspection technique described in Patent Document 2, a lighting device and a camera are supported on a robot arm of a robot disposed near an automobile body to be inspected, and the robot is moved along a predetermined route. By moving the arm, the outer surface of the vehicle body is imaged with a camera.

Japanese Patent No. 4315899 JP 2008-46103 A

  However, in the technique described in Patent Document 1, since the camera is of a fixed position type, and an industrial camera usually does not have a so-called autofocus function, the inspection object on the conveyor The distance between the outer surface of the vehicle body and the camera may not be constant under the influence of variations in the position and posture of the automobile body, and improvement in inspection accuracy cannot be expected due to poor focusing.

  On the other hand, since the technique described in Patent Document 2 is a method of moving a camera held by a robot arm, in an automobile production line in which a plurality of types of automobile bodies having different body shapes flow, a camera is previously provided for each body shape. Therefore, it is necessary to teach the movement route, and the cost is increased due to an increase in man-hours.

  Also, in the final inspection line of the produced automobile, it is normal for the automobile body to be continuously conveyed by a continuous type conveyor, so the camera held by the robot arm as described above is moved. As a premise, it is necessary to keep the line speed constant so that so-called surging does not occur, or the conveyor itself should be a tact feed conveyor, which is inflexible when applied to existing equipment, and there is still room for improvement Is leaving.

  The present invention has been made paying attention to such problems, and can be easily applied to existing equipment on the premise that the automobile body and the imaging means move relative to each other in the appearance inspection of the automobile body. Thus, there is provided an appearance inspection apparatus and an appearance inspection method capable of maintaining a constant distance between a vehicle body outer plate surface and an imaging means without incurring a significant cost increase and improving inspection accuracy. .

In the vehicle body appearance inspection apparatus according to the present invention, the vehicle body outer plate surface is imaged while relatively moving the vehicle body to be inspected and the imaging means, and surface defects on the vehicle body outer plate surface are extracted by image processing. In order to detect this as an appearance defect, in addition to the illumination unit, the imaging unit, and the image processing unit, a distance measuring unit that detects a distance between the imaging unit and the outer surface of the vehicle body, and imaging by the imaging unit are possible. Common support in which each of the vehicle width direction presence detection means for detecting that the vehicle body is present at the position, and the illumination means, imaging means, distance measurement means, and vehicle width direction presence detection means are mounted. and body was assumed to have a, a reciprocating drive means for advancing withdrawal movement with respect to the vehicle body outer panels face the support.
Then, on the condition that the presence detection of the vehicle body is detected by the vehicle width direction presence detection means, the advancing / retreating is performed so that the measured distance to the vehicle body outer plate surface detected by the distance measurement means becomes a specified distance. The illuminating means and the imaging means are made to follow the outer plate surface of the vehicle body together with the support via the driving means.

  The surface defect detected as an appearance defect on the outer surface of the vehicle body includes not only scratches and irregularities, but also foreign matter adhesion and dirt.

  According to the present invention, since the distance between the imaging unit and the outer surface of the vehicle body is maintained to be a predetermined distance, it is less affected by variations in the position and orientation of the automobile body that is the inspection object. As a result, the accuracy of the appearance inspection is improved, and the reliability of the inspection result is also improved.

  In addition, since there is no need to teach the camera movement path, there is an advantage that it can be easily applied to an existing final inspection line without requiring a large-scale remodeling as well as not causing an increase in cost due to an increase in man-hours. .

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the more concrete form for implementing the surface inspection apparatus of the motor vehicle body which concerns on this invention, and is schematic explanatory drawing of the whole apparatus. The figure which looked at the final inspection line shown in FIG. 1 from the moving direction back side of the vehicle. The principal part perspective view around the vehicle of FIG. Explanatory drawing of the electric actuator unit shown in FIG. The block diagram which shows the detail of the motor control part shown in FIG. 5 is a flowchart for shooting start control by each camera shown in FIGS. 4 is a flowchart for photographing interval control by each camera shown in FIGS. FIG. 2 is a schematic system block diagram of the main controller shown in FIG. 1. Explanatory drawing which shows the process sequence in step a6 of FIG. The flowchart which shows the rough process sequence in the main-control apparatus shown in FIG. The flowchart which shows the more detailed process sequence for extraction of a damage | wound. Explanatory drawing which shows the principle of the difference process in FIG.

  1 to 12 show a more specific form for carrying out an automobile body appearance inspection apparatus according to the present invention. In particular, FIG. 1 shows a schematic structure of the entire apparatus. The appearance inspection apparatus here is particularly suitable as an appearance inspection (surface inspection) of the outer surface of the manufactured vehicle (automobile) 1, particularly the painted surface of the vehicle body side surface portion 1 a including front and rear doors, front fenders and rear fenders. The purpose is to detect linear fine scratches that tend to occur on the side surface 1a of the vehicle body.

  As shown in FIG. 1, in the final inspection line 2 in the automobile production line, a plurality of vehicles 1 mounted on a continuous type slat conveyor 3 are continuously moving at a predetermined speed. An imaging device unit 4 is installed on the line side. The photographing equipment unit 4 is equipped with lighting devices 29, 30, 31 and a plurality of industrial cameras 32 as imaging means, which will be described later, and the photographing equipment unit 4 includes a control panel 6 and a main controller 5 in addition to the main controller 5. The output device unit 7 and the like are attached. In FIG. 1, only one imaging device unit 4 is illustrated, but the imaging device units 4 are arranged to face each other so as to be symmetrical with respect to the final inspection line 2.

  The main control device 5 is constituted by a personal computer in which image processing software for extracting a so-called appearance defect or surface defect is preliminarily installed. The main control device 5 includes a conveyor speed calculation unit 8, a photographing operation. The control unit 9 includes a vehicle type recognition unit 10, an image input unit 11, a flaw detection unit 12 as an image processing unit, an image connection unit 13, an examination table creation unit 14, an output unit 15, and the like.

  A signal from the conveyor encoder 16 of the drive system in the slat conveyor 3 is input to the conveyor speed calculation unit 8. As will be described later, the conveyor movement amount or the conveyor that is the detection output of the conveyor encoder 16 The photographing start timing of the vehicle body side surface 1a by the camera 32 is controlled by the speed information. The conveyor encoder 16 functions as a vehicle body movement amount detection means for detecting the movement amount of the vehicle 1 traveling on the slat conveyor 3.

  Further, a code reader 17 is installed as a vehicle information reading means on the ceiling portion on the carry-in start end side in the final inspection line 2. The code reader 17 reads, for example, barcode information on the work instruction card 18 attached to the windshield of the vehicle 1 to acquire vehicle information of the corresponding vehicle 1 and outputs it to the vehicle type recognition unit 10. It is possible to use QR code (registered trademark) information instead of the barcode information.

  Further, a monitor 19, a printer 20, a data server 21, and the like are connected to the output side of the main control device 5 as each device of the output device unit 7. The image processing result in the main control device 5 can be displayed on the monitor 19 for each vehicle or printed by the printer 20, and the image processing result data can be recorded and stored in the data server 21 together with the vehicle type information. It is supposed to be.

  The control panel 6 includes an illumination control unit 22, a motor control unit 23, a safety control unit 24, a line control unit 25, and the like, and is mainly mounted on the photographing apparatus unit 4 in cooperation with an external line control panel 26. It controls the relative positioning control of the lighting devices 29, 30, 31 and the camera 32 and the vehicle 1 in the vehicle width direction.

  2 shows a view of the final inspection line 2 shown in FIG. 1 as viewed from the rear side in the moving direction of the vehicle 1, and FIG. 3 shows a perspective view of the main part around the vehicle 1 of FIG. Two imaging device units 4 are arranged opposite to each other on the left and right line sides. Each photographing apparatus unit 4 is equipped with a rack 28 as a support body that can slide in the vehicle width direction with respect to a fixed base 27, and a plurality of (here, three) racks 28 are mounted on the rack 28. The lighting devices 29, 30, 31 and a plurality of cameras 32 are installed, and a photoelectric sensor 33 as a vehicle width direction presence detection means and a distance measurement sensor 34 as a distance measurement means are provided as non-contact sensors. It is.

  A linear type electric actuator unit (for example, ROBO Cylinder Series manufactured by IAI Corporation) 35 is provided at the bottom of the gantry 27 as an advancing / retreating drive means. The electric actuator unit 35 is controlled by the motor control unit 23 in FIG. 1, and as shown in FIG. 4, the slider 35b linearly moves back and forth (slides) in response to the activation of the motor unit 35a. The rack 28 is mounted. Therefore, the rack 28 can be moved back and forth by the operation of the electric actuator unit 35, that is, the rack 28 equipped with a plurality of lighting devices 29, 30, 31 and a plurality of cameras 32 can be slid in the vehicle width direction. ing. In order to avoid complication of the drawing, FIG. 2 shows seven cameras 32 on one side for the sake of convenience, and similarly FIG. 3 shows nine cameras 32 on one side. A total of 10 cameras 32 are juxtaposed in the direction. However, the number of cameras 32 is not particularly limited as long as the overall height of the image of the vehicle 1 can be covered.

  FIG. 5 shows details of the motor control unit 23 that controls the electric actuator unit 35. As is apparent from FIGS. 4 and 5, the electric actuator unit 35 includes an encoder 35 c as a feedback element, and forms a feedback loop with the motor control unit 23.

  The photoelectric sensor 33 is used to determine whether or not the vehicle 1 to be inspected is present in the vehicle width direction by irradiating the beam b <b> 1 downward and in the imaging area of the plurality of cameras 32. Therefore, the photoelectric sensor 33 functions as vehicle width direction presence detection means for detecting whether or not the vehicle 1 to be inspected is present in the imaging area. Further, the laser-type distance measuring sensor 34 as distance measuring means irradiates the vehicle body side surface 1a with the beam b2 so as to control the relative distance between each camera 32 and the vehicle 1 to be inspected to be a specified distance. The detected output is taken into the motor control unit 23 of FIGS.

  Then, on the condition that the vehicle 1 to be inspected is present in the imaging area by the plurality of cameras 32 as described above, the sensor output from the distance measuring sensor 34 is captured as a feedback signal into the motor control unit 23, The distance actually measured by the distance measuring sensor 34 is a predetermined distance, that is, the distance between the vehicle body side surface 1a, the plurality of lighting devices 29, 30, 31, and the plurality of cameras 32 is a predetermined distance. The rack 28 is slid under the operation of the electric actuator unit 35 so as to be ± α (for example, a specified distance of about ± 10 mm).

  In other words, the actually measured distance to the vehicle body side surface portion 1a detected by the distance measuring sensor 34, that is, the respective distances between the vehicle body side surface portion 1a and the plurality of lighting devices 29, 30, 31 and the plurality of cameras 32 are as follows. The plurality of lighting devices 29, 30, 31 and the plurality of cameras 32 are caused to follow the vehicle body side surface 1 a together with the rack 28 via the electric actuator unit 35 that is advancing / retreating driving means so as to be a predetermined distance. .

  As described above, the industrial camera 32 is so-called that the plurality of lighting devices 29, 30, 31 and the plurality of cameras 32 mounted on the common rack 28 are caused to follow the vehicle body side surface 1a. Since there is no autofocus function, the distance between the position of each camera 32 and the vehicle body side surface portion 1a is made constant by the following operation, and any part of the vehicle body side surface portion 1a can be focused. Become.

  Of the three illuminating devices 29 to 31 mounted on each rack 28, the illuminating device 30 at the center of the vehicle body side surface 1a is a general-purpose light source having a high wavelength stability and a wide irradiation range, as shown in FIG. The fluorescent lamp illumination device 30a and the diffusion plate 30b are combined so as to function as a relatively large surface light source, and the irradiation light from the fluorescent lamp illumination device 30a is diffused by the diffusion plate 30b so that there is no uneven illumination. It is considered that the parallel irradiation light is uniformly irradiated particularly on the vertical portion of the vehicle body side surface portion 1a.

  On the other hand, among the three lighting devices 29 to 31 mounted on the rack 28, the upper and lower lighting devices 29 and 31 are LED bar lighting devices 29a and 31a and diffuser plates 29b and 31b each having high light linearity. Are combined so as to function as a surface light source. The irradiation light from the LED bar lighting devices 29a and 31a is diffused by the diffusion plates 29b and 31b, and the parallel irradiation light without uneven irradiation is applied to the side surface portion 1a of the vehicle body. In particular, it is considered to uniformly irradiate the door waist portion and the side sill portion. The upper illumination device 29 for irradiating the door waist portion irradiates the side sill portion at the lower portion of the vehicle body while ensuring a relatively large distance from the vehicle body side surface portion 1a in order to make the irradiation light parallel light. Therefore, the lower illuminating device 31 has a side sill portion that tends to become a shadow anyway, so that the distance from the vehicle body side surface portion 1a is extremely small compared to the other illuminating devices 29 and 30. Thereby, the irradiation light from each illuminating device 29-31 will be equally irradiated to the range from a door waist part to a side sill among the vehicle body side parts 1a. At the same time, each camera 32 captures specularly reflected light from the vehicle body side surface 1a.

  The plurality of cameras 32 mounted on each rack 28 is a so-called two-dimensional solid-state imaging device type of CCD or CMOS type, and is high among the irradiated parts by the lighting devices 29 to 31 on the vehicle body side surface 1a. In order to image different areas in the vertical direction, in other words, in the vertical direction of the vehicle body, in order to individually capture a plurality of areas divided in the height direction among the irradiated parts by the lighting devices 29 to 31 on the vehicle body side surface 1a. Are lined up in a row. As is clear from FIGS. 2 and 3, the plurality of lighting devices 29 to 31 and the plurality of cameras 32 take the curvature shape in the vertical direction of the vehicle body side portion 1 a into consideration, as viewed from the front or rear of the vehicle 1. In view, it is arranged so as to follow the curvature shape of the vehicle body side surface portion 1a. As a result, the specularly reflected light from the side surface 1a of the vehicle body can be simultaneously photographed by the plurality of cameras 32 and the entire height of the vehicle body. Here, the uppermost camera 42 of the plural (10) cameras 32 shown in FIGS. 2 and 3 also serves as a shooting start control camera, as will be described later.

  That is, photographing (imaging) is performed in a state in which a plurality of cameras 42 and 32 having the vehicle body side face portion 1a directed to the vehicle 1 moving at a predetermined speed on the final inspection line 1 are fixed in the vehicle moving direction. Thus, the overall height of the vehicle body side surface 1a can be intermittently photographed (imaged) in synchronism with the movement of the vehicle 1 while sharing the imaged (imaged) parts by the respective cameras 42 and 32. Here, as will be described later, the amount of movement of the vehicle 1 on the final inspection line 1 is calculated, and if it is confirmed that the vehicle has moved by a predetermined distance, a plurality of cameras 42 and 32 are simultaneously activated to start photographing. It is assumed that the intermittent shooting operation by the plurality of cameras 42 and 32 for each predetermined movement amount is repeated until the entire length of the vehicle has passed.

  Here, FIG. 6 shows a flowchart for the shooting start control by the plurality of cameras 42 and 32, and FIG. 7 shows a flowchart for the shooting interval control by the plurality of cameras 42 and 32, respectively. As shown in FIG. 3, a photoelectric sensor 41 serving as a vehicle front-rear direction seating detection unit is provided above the slat conveyor 3, so if this photoelectric sensor 41 detects the passage of the vehicle 1, Using the detection signal of the photoelectric sensor 41 as a trigger, the external trigger mode of the uppermost shooting start control camera 42 is turned ON, and the shooting start control camera 42 automatically starts shooting (imaging). Subsequently, as shown in FIG. 6, the start of photographing of the photographing start control camera 42 is determined on the software stored in the main controller 5, and the remaining cameras 32 start photographing instantaneously. Thereafter, simultaneously with the end of shooting of all the cameras 42 and 32, the external trigger mode of the shooting start control camera 42 is turned off.

  Details of the shooting start timing control of each camera 32 other than the shooting start control camera 42 are as shown in FIG. Here, in consideration of fluctuations in the traveling speed of the vehicle 1 by the slat conveyor 3 such as so-called surging, the pulse signal from the conveyor encoder 16 shown in FIG. 1 is obtained, and the movement amount of the vehicle 1 by the slat conveyor 3 is determined in real time. calculate. Then, when the movement amount of the vehicle 1 is the designated movement amount that is the preset movement amount, that is, the designated distance Lx in FIG. 7, the trigger signal on the software described above is triggered. As described above, the photographing of each camera 32 other than the photographing start control camera 42 is started. Thereafter, the above operation is repeated each time the photographing of each camera 32 is completed. That is, the above operation is repeated until it can be confirmed from the total movement amount of the vehicle 1 that the photographing of the entire length of the vehicle has been completed.

  As described above, the vehicle 1 is detected by the photoelectric sensor 41, the origin of the so-called shooting start coordinates is determined, and the shooting start timing of the plurality of cameras 42 points 32 is controlled while measuring the movement amount of the vehicle 1. By doing so, it becomes difficult to be influenced by the surging of the conveyor speed, and the image detection timing control corresponding to the conveyor speed can be performed with high accuracy.

  FIG. 8 is a schematic system block diagram of the main controller 5 in the apparatus shown in FIG.

  As shown in the figure, following the initialization of the cameras 42 and 32 and the reading of the specification information (Step Sa1), the start information of the cameras 42 and 32 is acquired together with the vehicle information read by the code reader 17 ( Step a2). Thereafter, simultaneous shooting is started with all the cameras 42 points 32, and logic for detecting scratches on the painted surface, which is the vehicle body side surface 1a, is executed as described later (step a3). Then, after the captured images of each camera 42 points 32 are stored in a folder (step a4), the movement amount of the vehicle 1 is calculated based on the signal from the conveyor encoder 16 of FIG. 1, and the vehicle 1 moves by a predetermined distance. When the designated position is reached, the process proceeds to the next shooting (step a5). Such processing from step a2 to step a5 is repeated until the photographing of the entire vehicle 1 (full length) is improved. Note that the processing so far corresponds to the processing in the flowcharts of FIGS.

  Thereafter, the inspection table creation unit 14 in FIG. 1 summarizes the scratch detection results on the painted surface, that is, the scratch detection results for each image by the plurality of cameras 42 and 32, for each vehicle. The photographed image at 32 is combined, and the flaw detection result (image processing result) is output to the monitor 19 and the printer 20 in FIG. 1 (step a6). In the printer 20, the image of the side surface of the vehicle that has been combined is printed as it is as a hard copy inspection table 36 (see FIGS. 2 and 8), and a predetermined marking M is overlaid on the scratch detection site. This hard copy is used, for example, at the time of re-inspection or repainting by the worker in the next process. It should be noted that FIG. 9 is a diagram illustrating the processing in step a6 for easy understanding.

  Here, if attention is paid only to the image processing for the flaw detection, the processing procedure is as shown in step S1 to step S8 in FIG. 10, and more specifically as shown in FIG. The present embodiment is greatly characterized in that a so-called constant calibration function is added by a difference process between an image after luminance value correction and smoothing processing and an original image.

  In the scratch detection unit 12 as the image processing means of the main control device 5 in FIG. 1, if captured images of the cameras 42 and 32 are captured in step S11 in FIG. 11, contrast correction including luminance value correction is performed in step S12. To do. Here, information on the color, saturation, and luminance of the image is acquired, the average value and median value of the hue (Hue) are calculated, and the pixel value histogram of the acquired image is used as a contrast correction process including luminance value correction. Originally, the pixel value average is corrected so as to be constant. This is to correct the average pixel value of each input image so as to minimize the influence of uneven illumination light and differences in vehicle body color.

  In step S13, the image after contrast correction including the luminance value correction as described above is subjected to smoothing processing by a median filter, and a local master area such as a scratch is removed or blurred to artificially master. A good product image is created as an image. The smoothing process using the median filter has an effect of aligning pixel values of an image having a low or high local pixel value with the surrounding pixel values, and can estimate an image equivalent to a non-defective product from which local defects such as scratches have been removed. In addition, there is a feature that it is possible to maintain a gradual change in luminance of pixels such as uneven illumination.

  In the next step S14, as shown in FIG. 12, a difference process between the created non-defective image and the original image (image after luminance value correction) is executed, and only the fine linear scratch Q on the painted surface is poor in appearance. Or it extracts as a surface defect. In this difference processing, only local defects such as scratches can be extracted without being affected by uneven illumination, and such processing is always performed for each acquired image. In the next step S15, the area within the luminance value designated as the binarization process is subjected to the light / dark binarization process.

  In step S16 in FIG. 11, the connected regions of the feature points are extracted and the noise is removed, and the regions extracted by the previous binarization process (connected components) are extracted in order to extract the connected components of the feature points. To extract.

  In the next steps S17 and S18, detection of fine flaws or shallow line flaws Q by area expansion and extraction area designation is performed to reduce false detections. That is, in step S17, as primary feature value extraction, feature values within a specified area (number of pixels) are extracted, and the extracted region is expanded (enlarged). Further, in step S18, as the secondary feature quantity extraction, the feature quantity within the designated area (number of pixels) is extracted, and the scratch Q in FIG. 12 is determined.

  Here, as described above, the difference-processed image is binarized and a defect such as a scratch or a defective portion is extracted. However, since a very shallow scratch is extracted as a broken point, Sometimes it cannot be judged. Therefore, by expanding the result after the binarization processing as described above, a very shallow wound Q can be extracted as a continuous region. On the other hand, there is a possibility that the extracted area may include an edge portion such as a part other than the scratch Q. Therefore, in order to distinguish small areas such as scratches Q from other areas, it is determined whether or not the extraction area is within the specified area (number of pixels). By cutting large areas such as edges of other parts, it is possible to reduce false detection and accurately extract only appearance defects or surface defects based on the scratch Q.

  In other words, in the processing in steps S17 and S18, in addition to the effect of emphasizing local defects such as a scratch Q on the surface with a large curvature change, an effect of removing a gradual shading change due to uneven illumination is expected. Therefore, it is possible to detect scratches Q that occur in shapes with many curvature changes without registering a specific pattern, and it is possible to reduce false detection by eliminating the influence of edges of other parts. It becomes.

  Further, as described above, the actually measured distance to the vehicle body side surface portion 1a detected by the distance measuring sensor 34, that is, the vehicle body side surface portion 1a, the plurality of lighting devices 29, 30, 31 and the plurality of cameras 32 are formed. A plurality of lighting devices 29, 30, 31 and a plurality of cameras 42, 32 are attached to the side surface 1a of the vehicle body together with the rack 28 via an electric actuator unit 35 that is an advancing / retreating drive means so that each distance becomes a predetermined distance. Since the tracking operation is performed, even if each camera 42, 32 does not have a so-called autofocus function, the distance between the position of each camera 42, 32 and the vehicle body side surface portion 1a becomes constant, and the vehicle body side surface portion 1a. When photographing any part of the throat, the focus can be adjusted. As a result, it becomes difficult to be affected by variations in the position and posture of the vehicle 1 that is the inspection object, the accuracy of the appearance inspection is improved, and the reliability of the inspection result is also improved.

  In particular, by causing the cameras 42 and 32 and the plurality of lighting devices 29, 30, and 31 to follow the vehicle body side surface 1a, they are less affected by illumination unevenness and the like, and the accuracy of the appearance inspection is further improved.

  In addition, as shown in FIGS. 2 and 3, since the lighting devices 29 to 31 and the plurality of cameras 42 and 32 are arranged in accordance with the curvature of the vehicle body side surface 1a, the lighting device 29 is appropriately applied to the curved surface portion. Since the illumination light from -31 can be irradiated, it becomes possible to accurately detect appearance defects or surface defects such as scratches at the same site.

  Furthermore, as described above, after the vehicle 1 is detected by the photoelectric sensor 41 and the origin of the so-called shooting start coordinates is determined, the shooting start of the plurality of cameras 32 is measured while measuring the movement amount of the vehicle 1. By controlling the timing, it is less susceptible to conveyor speed surging and the like, and image detection timing control corresponding to the conveyor speed can be performed accurately. Therefore, even if the speed of the slat conveyor 3 that transports the vehicle 1 changes, an inspection image can be acquired at an accurate timing, so there is no inspection omission due to a shift in the image detection timing, and the position of the inspected inspection is accurately inspected. It can be displayed on the staff. In other words, it is possible to prevent the inspection omission due to the speed change of the slat conveyor 3 and the deterioration of the detection position accuracy of the scratches.

1 ... vehicle 1a ... vehicle body side surface (painted surface)
DESCRIPTION OF SYMBOLS 3 ... Slat conveyor 4 ... Imaging equipment unit 5 ... Main controller 12 ... Scratch detection part (image processing means)
16. Conveyor encoder (vehicle body movement amount detection means)
28 ... Rack (support)
29 ... Illumination device (illumination means)
30 ... Illumination device (illumination means)
31 ... Illumination device (illumination means)
32 ... Camera (imaging means)
33 ... Photoelectric sensor (vehicle width direction presence detection means)
34 ... Ranging sensor (ranging means)
35 ... Electric actuator unit (advance / retreat drive means)
41. Photoelectric sensor (body longitudinal presence detection means)
42 ... Camera (imaging means, camera for start control)
Q ... Scratches (surface defects)

Claims (10)

A device that picks up an image of the outer surface of the vehicle body while relatively moving the vehicle body to be inspected and the imaging means, extracts surface defects on the outer surface of the vehicle body by image processing, and detects them as defective appearance. And
Illuminating means for illuminating the vehicle body outer plate surface with illumination light;
An imaging means that is capable of moving back and forth with respect to the vehicle body outer plate surface, and that images an irradiation site by illumination light in the vehicle body outer plate surface;
An image processing unit that performs image analysis using the image captured by the imaging unit as an input, extracts a surface defect on the outer surface of the vehicle body, and detects this as an appearance defect;
Distance measuring means for detecting the distance between the imaging means and the outer surface of the vehicle body;
Vehicle width direction presence detection means for detecting that the vehicle body is present at a position where imaging by the imaging means is possible;
A common support on which each of the illumination means, the imaging means, the distance measurement means, and the vehicle width direction presence detection means is mounted;
A reciprocating drive means for moving withdrawal proceeds with respect to the vehicle body outer plate surface of the support,
The equipped,
Under the condition that the presence detection of the vehicle body is performed by the vehicle width direction presence detection means, the measured distance to the vehicle body outer plate surface detected by the distance measurement means is set via the advance / retreat drive means so as to be a prescribed distance. though automobile body appearance inspection apparatus according to claim Rukoto adapted to follow-up operation for each support body outside plate surface illuminating means and imaging means Te. The imaging means, automobile body appearance inspection apparatus according to claim 1, characterized in der Rukoto which images the vehicle body outer plate surface of the automobile body to be continuously running at a predetermined speed by a conveyor. Supports on which the illumination means, imaging means, distance measurement means, and vehicle width direction presence detection means are respectively mounted are provided on both sides of the conveyor line of the automobile body by the conveyor,
3. The appearance inspection of an automobile body according to claim 2 , wherein each support is individually operated to follow the outer plate surface of the vehicle body via an independent forward / backward drive means for each of the supports. apparatus. A plurality of the imaging means are juxtaposed along the height direction of the vehicle body so as to individually capture a plurality of regions divided in the height direction of the vehicle body,
The vehicle body according to any one of claims 1 to 3 , wherein the plurality of imaging means are arranged in accordance with a shape of a side surface of the vehicle body in a front view or a rear view of the vehicle body. Appearance inspection device. The vehicle body appearance inspection apparatus according to any one of claims 1 to 4 , wherein the vehicle body outer plate surface of the vehicle body is a painted surface after painting . In this method, the vehicle body outer plate surface is imaged while the vehicle body to be inspected and the imaging means are moved relative to each other, and surface defects on the vehicle body outer plate surface are extracted by image processing and detected as defective appearance. And
The vehicle body is seated at a position where imaging means for imaging the outer surface of the vehicle body, distance measuring means for detecting the distance between the imaging means and the outer surface of the vehicle body, and a position where imaging by the imaging means is possible. Vehicle width direction presence detection means is mounted on a support that can move forward and backward with respect to the vehicle body outer plate surface,
On the condition that the presence detection of the vehicle body is detected by the vehicle width direction presence detection means, the support body moves forward and backward so that the measured distance to the vehicle body outer plate surface detected by the distance measurement means becomes a specified distance. automotive vehicle body appearance inspection method you characterized and Turkey were additionally sub operating an imaging unit in the vehicle body outside plate surface with. After imaging the vehicle body outer plate surface of an automobile body as an inspection object continuously running at a predetermined speed by a conveyor, the surface defect on the vehicle body outer plate surface is extracted by image processing and detected as an appearance defect. A device,
Illuminating means for illuminating the vehicle body outer plate surface with illumination light;
An imaging means that is capable of moving back and forth with respect to the vehicle body outer plate surface, and that images an irradiation site by illumination light in the vehicle body outer plate surface;
An image processing unit that performs image analysis using the image captured by the imaging unit as an input, extracts a surface defect on the outer surface of the vehicle body, and detects this as an appearance defect;
Distance measuring means for detecting the distance between the imaging means and the outer surface of the vehicle body;
Forward / backward drive means for moving the imaging means forward / backward with respect to the vehicle body outer plate surface so that a distance between the image pickup means and the vehicle body outer plate surface is a specified distance;
Vehicle width direction presence detection means for detecting that the vehicle body is present at a position where imaging by the imaging means is possible;
Vehicle body front-rear direction seating detection means for detecting that the vehicle body is seated at a position where imaging by the imaging means is possible in the traveling direction of the vehicle body by the conveyor;
With
Under the condition that the presence detection of the vehicle body is performed by the vehicle width direction presence detection means, the measured distance to the vehicle body outer plate surface detected by the distance measurement means is set via the advance / retreat drive means so as to be a prescribed distance. The image pickup means is adapted to follow the outer surface of the vehicle body,
The longitudinal direction of the vehicle body Presence detection first have the appearance inspection apparatus of the automotive vehicle body you wherein Rukoto so imaging start timing is controlled by the imaging unit based on the detection output of the unit. A plurality of the imaging means are juxtaposed along the height direction of the vehicle body so as to individually capture a plurality of regions divided in the height direction of the vehicle body,
8. The appearance inspection apparatus for an automobile body according to claim 7 , wherein each imaging means intermittently images in a plurality of times in the front-rear direction of the automobile body in synchronization with the movement of the automobile body running on the conveyor. . A vehicle body movement amount detecting means for detecting a movement amount of the automobile body traveling by the conveyor is provided,
The imaging means automobile body appearance inspection apparatus according to claim 8, wherein each time imaging to Rukoto upon detecting movement amount of the vehicle body movement amount detecting means reaches a set amount of movement. 10. The automobile body appearance inspection apparatus according to claim 9, wherein the imaging by each imaging means for each set movement amount is repeated until the movement amount of the automobile body traveling by the conveyor reaches the full length of the vehicle body.

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