JP2009068920A - Camera adjustment method and camera adjustment system - Google Patents

Abstract

An object of the present invention is to provide a camera adjustment method capable of adjusting a camera installed in accordance with each inspection target part of a vehicle with one type of vehicle even when a plurality of types of vehicles are mixed.
A step of selecting a reference vehicle as a reference vehicle from a plurality of types of vehicles (step S2), and a displacement amount of a position of an inspection target portion of another type of vehicle with respect to the inspection target portion of the reference vehicle (Step S2), setting a displacement amount display device attached to the reference vehicle and indicating the displacement amount of the position (step S4), and based on the set displacement amount display device, Adjusting the camera that images the inspection target portions of the plurality of types of vehicles (steps S6 and S7).
[Selection] Figure 3

Description

  The present invention relates to a camera adjustment method and a camera adjustment system.

  Components such as vehicle door mirrors, wipers, brake lamps, and the like are attached with specific quality assurance marks (eg, engraved part codes) that guarantee their quality. When an automobile is completed and shipped to the market, it is necessary to inspect whether or not a component code is imprinted on each component of the automobile in order to confirm that there is no problem in quality. Conventionally, this inspection work has been performed by an operator who actually confirms with his own eyes. However, with the recent improvement in performance of digital cameras, it has become possible to use an image inspection apparatus using a camera in order to determine whether or not a specific quality assurance mark is present on a vehicle component.

  The image inspection apparatus is used, for example, in an inspection line of an automobile, and when the automobile enters and stops in an imaging area captured by the camera, the automobile component parts are imaged by the camera, It is determined whether the component has a quality assurance mark.

  In order to accurately determine the quality assurance mark of a component (inspection target part) with this image inspection apparatus, it is necessary to adjust the position or focus of the camera so that the inspection target part of the automobile is within the imaging range of the camera. It is. Further, even when the entire automobile is imaged with a single camera, such as when the resolution of the camera is lowered, it is difficult to discriminate the quality assurance code due to limitations on the number of pixels of the camera. Therefore, it is necessary to provide and adjust a camera corresponding to the inspection target part so that the quality assurance code of the inspection target part can be recognizable.

As a conventional camera positioning method, in order to represent the error of the stop position of the traveling carriage, the inspection target part with a scale or marker attached is imaged with the camera, and the camera position is adjusted by checking the marker in the captured image. (For example, refer to Patent Document 1).
JP-A-9-93570

  However, when a camera is installed in a place where automobiles of various shapes are mixed, such as an automobile inspection line, it is necessary to capture all types of automobiles with the camera, and even the position of a single door mirror varies depending on the vehicle type. There was a problem that adjustment of the camera was difficult. That is, in the automobile inspection line, automobiles enter and are inspected one by one. Therefore, when adjusting the camera position, it is not possible to image the inspection target portions of automobiles of different vehicle types at once. Therefore, after adjusting the camera position with respect to one type of automobile, confirmation / adjustment of whether or not the inspection target part of another type of automobile is imaged in the imaging range of the camera is repeatedly performed, Adjustment took a lot of time.

  As described above, the present invention solves the above-described problems, and even when a plurality of types of vehicles are mixed, the inspection target portion of all types of vehicles is imaged by adjusting the camera with only one type of vehicle. An object of the present invention is to provide a camera adjustment method that can be performed.

  The above object of the present invention is achieved by the following means.

  The camera adjustment method of the present invention selects one type of vehicle as a reference vehicle from a plurality of types of vehicles, calculates the displacement amount of the position of the inspection target portion of another type of vehicle relative to the inspection target portion of the reference vehicle, and the displacement The camera is adjusted based on a displacement amount display device indicating the amount.

  The camera adjustment system of the present invention selects one type of vehicle as a reference vehicle from a plurality of types of vehicles, and calculates a displacement of the position of the inspection target portion of another type of vehicle relative to the inspection target portion of the reference vehicle; A displacement amount display device showing the displacement amount and a camera are included.

  According to the present invention, even when a plurality of types of vehicles are mixed, it is not necessary to actually prepare all types of vehicles, and by adjusting the camera with one type of vehicle, inspection of all types of vehicles is possible. The target part can be imaged.

  A camera adjustment method and system according to a preferred embodiment of the present invention will be described below with reference to the drawings.

  The camera adjustment method according to the embodiment of the present invention selects one type of vehicle from a plurality of types of vehicles, and calculates a displacement amount of the position of the inspection target portion of another type of vehicle relative to the inspection target portion of the one type of vehicle. Further, the present invention is characterized in that the camera is adjusted based on a displacement amount display device that indicates the displacement amount.

  In the embodiment of the present invention, a case where a camera adjustment method is applied to an automobile inspection line that inspects and inspects a plurality of types of automobile inspection target parts by using a camera will be described as an example. That is, in this embodiment, an automobile is adopted as an example of a vehicle.

  First, the automobile inspection line will be briefly described with reference to FIG. FIG. 1 is a diagram illustrating an example of an automobile inspection line to which the camera adjustment method of the present embodiment is applied.

  The automobile inspection line 1 includes a travel path 3 into which the automobile 2 enters, a car stop 4 that is a stop position of the automobile 2 installed on the travel path 3, cameras 5a to 5f that capture images of each inspection target portion of the automobile 2, and a camera 5a. An image inspection device 7 for receiving and displaying the imaging results of the respective mounting bases 6 to 5f and the cameras 5a to 5f is arranged.

  The cameras 5a to 5f image components such as a door mirror, a wiper, a wheel, and a brake lamp, and function as an imaging unit. The cameras 5a to 5f can be configured by an imaging element such as a CCD element and other optical systems, and the configuration itself is the same as that of a general camera, and thus detailed description thereof is omitted. The imaging results captured by the cameras 5a to 5f are transmitted to the image inspection apparatus 7 via communication means (not shown) such as a cable. In this embodiment, the number of cameras is exemplified as six. However, the number of cameras actually required is determined according to the number of inspection target parts of the automobile.

  The mounting bases 6 are installed on both sides of the traveling path 3 and are bases for mounting a camera corresponding to each inspection target part so that each inspection target part can be imaged. Can be installed at.

  The image inspection device 7, for example, images each inspection target part of the automobile 2 with the cameras 5 a to 5 f, and determines whether or not there is a specific part code in each inspection target part based on the captured image result, The result is displayed on a display unit included in the image inspection apparatus 7. The image inspection device 7 detects the component code in the image data by matching the image data captured by the cameras 5a to 5f with the component code data (reference data) stored in advance. Similar to the conventional image inspection method, the image inspection method is performed by, for example, scanning the reference data on the screen on which the constituent articles in the captured image data are displayed, and detecting the component code in the image data. . The part code is, for example, a code stamped on a component part constituting an automobile, and is a quality assurance mark that guarantees the quality of each component part. The size of the part code is, for example, about 1.5 cm to 2 cm.

  Hereinafter, the camera adjustment system of this embodiment will be described in detail. The camera adjustment system of the present embodiment is for adjusting the cameras 5a to 5f installed in the automobile inspection line 1, and includes a computer 10 and a computer 10 that calculate the displacement amount of the position of the inspection target portion depending on the vehicle type. A displacement amount display device 20 is provided for indicating the displacement amount of the calculated position.

  The computer 10 selects one type of reference vehicle from a plurality of types of vehicles as a reference vehicle, and calculates a displacement amount of the position of the inspection target portion of another type of vehicle relative to the inspection target portion of the reference vehicle. , Function as a calculation means. The computer 10 includes, for example, a CPU for performing various operations, a RAM that temporarily stores data and functions as a working area, a ROM that stores a program, a storage device that stores design data of a plurality of types of vehicles, and It consists of a display unit. The displacement amount of the position calculated by the computer 10 is displayed on the display unit, for example. Here, the displacement amount of the position is, for example, each inspection object of the reference vehicle when the center of the front wheel (axle position) viewed from the side of the vehicle and the center position viewed from the front of the vehicle is the origin. It is a relative position of each inspection object part of other kinds of vehicles to a part. The means for calculating the displacement amount of the position will be described later.

  The displacement amount display device 20 is attached to the reference automobile and indicates the displacement amount of the position of each inspection object portion calculated by the computer 10. As shown in FIG. 2, the displacement amount display device 20 includes a bar-shaped first member 21, a bar-shaped second member 22 that intersects the first member 21, a plane represented by the first member 21, and the second member 22. It has a rod-shaped third member 23 having a predetermined angle, and a swing part 24 that allows the first member 21 and the second member 22 to swing. The displacement amount display device 20 has markers (21a, 22a, 23a) attached to the first member 21, the second member 22, and the third member 23, respectively. The amount of displacement of the calculated position can be represented three-dimensionally. The first member 21 and the second member 22 are used to adjust the viewing angle of the camera (up / down / left / right direction seen from the camera), and the third member 23 is used to adjust the depth direction seen from the camera. The predetermined angle is an angle at which the first member 21, the second member 22, and the third member 23 can represent a three-dimensional displacement amount. The third member can be installed, for example, in the normal direction of the plane represented by the first member 21 and the second member 22.

  The displacement amount display device 20 further includes attachment means 25 for attachment to the automobile 2, and the attachment means 25 is a hook that is hooked on a part of a work such as a tire as shown in FIG.

  The camera adjustment method according to the present embodiment is executed using the camera adjustment system configured as described above.

  Next, the camera adjustment method of the present embodiment will be described based on the flowchart shown in FIG. In the following process, a case where the cameras 5a to 5f on the automobile inspection line 1 are adjusted for three types of automobiles 2A, 2B, and 2C having different vehicle shapes will be described as an example. Then, the vehicle 2A is a reference vehicle that is actually run on the vehicle inspection line 1 and serves as a reference for adjusting the camera. In addition, it is assumed that each inspection target portion of the automobile to be inspected on the automobile inspection line 1 is a component part of a door mirror, a wiper, a backlight, and a wheel as an example. Furthermore, the camera 5a images a wheel, the camera 5b images a door mirror, the cameras 5c and 5d backlight, and the cameras 5e and 5f image a wiper.

  First, the cameras 5a to 5f are installed on the automobile inspection line 1 according to each inspection target part of the automobile (step S1). The cameras 5a to 5f can be installed according to the experience of the operator in consideration of the position and height of the components of the automobile, for example.

  Next, the relative position of the inspection target portion in the other automobiles 2B and 2C, that is, the displacement amount of the position with respect to one type of automobile 2A serving as a reference, is calculated from the CAD drawing using the computer 10 (step) S2). Here, when calculating the displacement amount of the position, the center position of the front wheel (axle position) viewed from the side of the automobile and the center position seen from the front of the automobile is the origin, and the direction in which the automobile travels is the x-axis direction The height direction of the vehicle is the y-axis direction, and the direction perpendicular to the x-axis direction and the y-axis direction is the z-axis direction. The displacement amount of the position of each inspection object part is, for example, from the center of the inspection object part of the automobile 2A (the center position of the engraved part code) to the center position of the inspection object parts of the automobile 2B and the automobile 2C. Displacement amount. At this time, as an example, the displacement amount of the positions of the automobile 2A (solid line shown in FIG. 4) and the automobile 2B (dashed line shown in FIG. 4) on the xy-axis plane will be described with reference to FIG. FIG. 4 shows wipers (a1, b1), door mirrors (a2, b2), backlights (a3, b3), and wheels (a4, b4) as a part of the inspection target part. The displacement amount of the position of the automobile 2A and the automobile 2B is as follows: wiper (10 mm in the x-axis direction, 80 mm in the y-axis direction), door mirror (180 mm in the x-axis direction, 130 mm in the y-axis direction), backlight (in the x-axis direction) 455 mm, 120 mm in the y-axis direction), and wheel (270 mm in the x-axis direction). Note that the displacement amount of the position in the z-axis direction can be obtained in the same manner as the displacement amount of the position in the xy-axis direction, but the description thereof is omitted here.

  Further, the deviation amount of the stop position of the automobile 2A stopped in the imaging area captured by the cameras 5a to 5f is calculated from the stop 4 and the wheel guide 8 in the automobile inspection line 1 and the tire size of the automobile 2A. . As shown in FIG. 5 (a), the car stop 4 is provided on the travel path 3 on the automobile inspection line 1 and restricts the excessive entry of the automobile 2A. Since the car stop 4 restricts the traveling direction of the automobile 2 </ b> A, the variation in the x-axis direction is calculated from the car stop 4. As shown in FIG. 6B, the wheel guide 8 is provided along both ends of the travel path 3, for example, and restricts the automobile 2A to travel in the center of the travel path 3 and stop. Is. Since the wheel guide 8 limits the z-axis direction, the variation in the z-axis direction is calculated from the wheel guide 8. The wheel guide 8 can also serve as a derailment guard when a pit is provided for an operator to enter and work.

  Next, the automobile 2A, which is a reference automobile, is put into the traveling path 3 of the automobile inspection line 1 and stopped at a position corresponding to the vehicle stop 4 and the wheel guide 8 (step S3).

  Next, the displacement amount of the position calculated by the computer 10 is marked on the displacement amount display device 20 (step S4). First, in order to adjust the camera 5a, the position change amount of the wheel to be imaged and inspected by the camera 5a is marked on the displacement amount display device 20. Specifically, an operator moves a mark attached to each member of the displacement amount display device 20 on the basis of the calculated displacement amount of the position, and the displacement amount is displayed on the displacement amount display device 20. Let them express. The movement of the mark of the displacement amount display device 20 is performed, for example, by setting the center of the swinging portion 24 as the center of the inspection target portion of the automobile 2A (the center position of the engraved part code) and the automobile 2B and the automobile 2C. Move and set the displacement of the center position of the inspection target part. Further, the mark of the displacement amount display device 20 is moved by the amount of deviation of the stop position of the automobile 2A.

  Next, the displacement amount display device 20 in which the displacement amount of the position is set is attached to each inspection target portion of the automobile 2A (step S5). As described above, it is desirable that the mounting position is provided so that the swinging portion 24 is in contact with or close to the center of the inspection target portion of the automobile 2A. As shown in FIG. 2, this attachment method can be attached using a hook that is hooked on a part of the tire. A clamp type glass suction cup stay (see FIG. 6A) can be used when attached to glass, and a magnet clamp stay (see FIG. 6B) can be used when attached to the metal of the body. Of course, the displacement amount of the position can be appropriately adjusted in consideration of the shape of the attaching means. Further, by adjusting the swinging portion 24 of the displacement amount display device 20, it is possible to adjust errors such as the vehicle body stopping obliquely.

  Next, the angle and attachment position of the camera 5a are adjusted while viewing the imaging result captured by the camera 5a, for example, while looking at the monitor of the image inspection apparatus 7 (step S6). That is, the inspection target part is imaged by the camera 5a so that the marker of the displacement amount display device 20 is imaged, and the position of the camera 5a is adjusted by confirming the marker reflected in the captured image.

  Next, the camera amplifier is set for the imaging result captured by the camera 5a while looking at the monitor of the image inspection apparatus 7, for example (step S7). In other words, the focal length of the camera 5a can be set by setting the camera amplifier.

  As shown in FIG. 7, the adjustment in the depth direction when viewed from the camera is calculated by calculating the amount of displacement due to the difference in vehicle body shape, and adding the amount of variation in the vehicle stop position so that it is between the maximum depth and the minimum depth viewed from the camera. Adjust the camera focal length. As shown in FIG. 8, when the displacement amount of the inspection target portion is ½ or more of the camera depth of field, there is a possibility that the depth of field may deviate depending on the camera setting position. The camera position is adjusted using the mark on the third member.

  Note that if the amount of displacement of the position of the inspection target portion for each vehicle type is less than ½ of the camera depth of field, all the inspection target portions for each vehicle type fall within the depth of field. Accordingly, the viewing angle (up / down / left / right direction viewed from the camera) can be adjusted using the biaxial displacement amount display device 20 including the first member 21 and the second member 22 that do not use the third member 23. . In addition, the camera's viewing angle should be set to multiple cameras instead of a single camera if it is known that the inspection target will move beyond the resolution that allows correct / incorrect determination when the inspection target is photographed. Or use a model with high camera performance (number of pixels).

  Subsequently, the cameras 5b to 5f are also repeatedly adjusted (step S8: No). If adjustment of all the cameras 5a-5f is complete | finished (step S8: Yes), the motor vehicle 2A will be withdrawn from the motor vehicle inspection line 1, and the adjustment work of the motor vehicle 2A will be complete | finished.

  Next, the automobile 2B is put into the traveling path 3 of the automobile inspection line 1 and stopped at a position corresponding to the vehicle stop 4 and the wheel guide 8 (step S9).

  Next, it is verified whether or not each inspection target part of the automobile 2B can be imaged with the adjusted cameras 5a to 5f. If the imaging is possible and the camera position needs to be changed (step S10: No), again, Adjustment work of the automobile 2A is performed. Of course, in this adjustment operation, only the camera that cannot image the automobile 2B has to be adjusted.

  Then, as a result of verifying whether or not each inspection target part of the automobile 2B can be imaged, if there is no change in the camera position (step S10: Yes), the process proceeds to the next step S11.

  Next, the automobile 2C is put into the traveling path 3 of the automobile inspection line 1 and stopped at a position corresponding to the vehicle stop 4 and the wheel guide 8 (step S11).

  Next, it is verified whether or not each inspection target part of the automobile 2C can be imaged with the adjusted cameras 5a to 5f. If the imaging is possible and the camera position needs to be changed (step S12: No), again, Adjustment work of the automobile 2A is performed. In addition, this adjustment work should just adjust only the camera in which the imaging | photography of the motor vehicle 2C was impossible similarly to said step S10.

  Next, as a result of verifying whether or not each inspection target part of the automobile 2C can be imaged, if there is no change in the camera position (step S12: Yes), the camera adjustment process is terminated.

  As described above, according to the camera adjustment method of the present embodiment, it is not necessary to actually prepare all types of vehicles, and it is possible to adjust the cameras installed according to the inspection target portion with one type of vehicle. And the processing time for the operator to adjust the camera can be shortened.

  Here, as a reference example, a conventional camera adjustment method will be briefly described with reference to FIG. In an automobile inspection line, since vehicles are usually entered and inspected one by one, when adjusting the camera position, it is impossible to pick up images of the inspection target parts of vehicles of different vehicle types at once. Therefore, after the adjustment work (A) is performed on one type of automobile 2A, the automobile 2B is loaded, and the adjustment work (B) similar to the adjustment work (A) is performed on the automobile 2B. Then, the automobile 2A is again introduced, verified, and if the camera position needs to be changed, the adjustment work (A) of the automobile 2A needs to be performed again. The same applies after the adjustment work (C) is performed on the automobile 2C, and the adjustment works (A) and (B) of the automobile 2A or 2B are repeatedly performed. Further, as the number of vehicle body shapes increases, confirmation / adjustment of whether or not the inspection target part of another type of vehicle is imaged in the imaging range of the camera adjusted by one type of vehicle is repeated. It took a lot of time to adjust the camera position.

  Therefore, according to the camera adjustment method of the present embodiment, unlike the conventional case, the camera adjustment is performed based on the displacement amount display device that indicates the displacement amount of the position of the inspection target portion of another type of vehicle relative to the reference vehicle. The camera adjustment work is performed only for one type of reference vehicle, and the adjustment work for other types of vehicles can be eliminated.

  In addition, by using the design data of multiple types of vehicles to be inspected to calculate the displacement amount of the position of the inspection target portion of another type of vehicle relative to the inspection target portion of the reference vehicle, the assembly of the vehicle is actually completed. Even if not, the camera can be adjusted in consideration of them at the equipment adjustment stage of the image inspection apparatus.

  Furthermore, the displacement amount display device has a rod-shaped first member, a rod-shaped second member that intersects with the first member, and a swinging portion that allows the first member and the second member to swing. Thus, the angle can be adjusted freely according to the installation of the camera. Further, by moving the markers attached to the first member and the second member of the displacement amount display device, the displacement amount is visualized so that it can be easily recognized by the operator and the camera can be easily adjusted. Can do.

  Further, the displacement amount display device includes a rod-shaped third member having a predetermined angle with the plane represented by the first member and the second member, and each of the first member, the second member, and the third member The depth direction of the camera can also be visualized by moving the marker attached to.

  Furthermore, by moving the marker by the amount of deviation of the stop position of the reference vehicle that stops in the imaging area captured by the camera, even if there is a variation in the stop position of the vehicle driven by the operator, the camera An image can be reliably captured.

  Furthermore, by attaching attachment means attached to the vehicle, such as suction cups, magnet clamps, or hooks hooked to a part of the workpiece, the displacement amount display device can easily display the displacement amount on the reference vehicle regardless of the installation location of the vehicle. The device can be attached.

  The preferred embodiments of the present invention have been described above. However, the present invention should not be limited to the above embodiments, and does not depart from the spirit and scope expressed in the claims. Various modifications, additions, and omissions are possible by those skilled in the art.

  For example, in this embodiment, the computer 10 calculates the amount of displacement of the position of the inspection target portion of another type of vehicle relative to the inspection target portion of the reference vehicle using the design data. It is also possible to calculate the displacement amount of the position on the desk from the design drawing.

  Moreover, in this embodiment, although the displacement amount display apparatus displayed displacement amount using the rod-shaped 1st member, 2nd member, and 3rd member, shape itself is not restricted to this, For example, a 1st member and Instead of the second member, a flat plate may be used to mark the displacement amount on the flat plate.

  Furthermore, in the present embodiment, an automobile is used as an example of a vehicle. However, the present invention is not limited to an automobile, and can of course be used for other vehicles such as a motorcycle.

It is a figure which shows an example of the motor vehicle inspection line to which the camera adjustment method of this embodiment is applied. It is a figure which shows an example of the displacement amount display apparatus used by this embodiment. It is a flowchart which shows the camera adjustment method of this embodiment. It is a figure which shows the displacement amount of the position on the design data of a motor vehicle. It is a figure for demonstrating the deviation | shift amount of the stop position of the motor vehicle which stops in the imaging area which a camera images. It is a figure which shows an example of the attachment means of a displacement amount display apparatus. It is a figure for demonstrating the depth of field of a camera. It is a figure for demonstrating the depth of field of a camera. It is a flowchart which shows the conventional camera adjustment method.

Explanation of symbols

1 automobile inspection line,
2 cars,
3 road,
4 Car stops,
5a-5f camera,
6 Mounting base,
7 Image inspection device,
10 computers,
20 Displacement amount display device.

Claims (8)

Selecting one type of reference vehicle as a reference vehicle from a plurality of types of vehicles;
Calculating the amount of displacement of the position of the inspection target portion of another type of vehicle relative to the inspection target portion of the reference vehicle;
Setting a displacement amount display device attached to the reference vehicle and indicating a displacement amount of the position;
Adjusting a camera that images the inspection target portion of the plurality of types of vehicles based on the set displacement amount display device;
A camera adjustment method comprising:   2. The camera adjustment method according to claim 1, wherein in the step of calculating the amount of displacement, the amount of displacement is calculated from design data of the plurality of types of vehicles. The displacement amount display device has a rod-shaped first member, a rod-shaped second member that intersects with the first member, and a swinging portion that allows the first member and the second member to swing,
2. The camera adjustment method according to claim 1, wherein the step of setting the displacement amount display device indicates the displacement amount by moving a marker attached to each of the first member and the second member. . The displacement amount display device further includes a rod-shaped third member having a predetermined angle with a plane represented by the first member and the second member,
The step of setting the displacement amount display device indicates the displacement amount by moving a marker attached to each of the first member, the second member, and the third member. Camera adjustment method.   The step of setting the displacement amount display device further includes a step of moving the marker by an amount of shift of a stop position of a reference vehicle that stops in an imaging region captured by the camera. Item 5. The camera adjustment method according to Item 4.   The camera adjustment method according to claim 1, wherein the displacement amount display device includes attachment means attached to the vehicle.   The camera adjusting method according to claim 6, wherein the attachment means is a suction cup, a magnet clamp, or a hook that is hooked on a part of a workpiece. A calculation means for selecting one type of reference vehicle as a reference vehicle from a plurality of types of vehicles, and calculating a displacement amount of a position of an inspection target portion of another type of vehicle relative to the inspection target portion of the reference vehicle;
A displacement amount display device attached to the vehicle and indicating a displacement amount of the position;
A camera that images the inspection target portion of the plurality of types of vehicles adjusted based on the displacement amount display device;
A camera adjustment system comprising:

Images