JP2851092B2 - Position detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention obtains an image signal by capturing a line light source for forming a line light image on a vehicle body carried into a vehicle body assembly line and a line light image on the vehicle body. The present invention relates to a position detection device that includes an imaging unit and detects a position of a vehicle body based on an image signal obtained from the imaging unit.

(Prior Art) When a window glass is mounted on a window glass mounting frame of a vehicle body on a vehicle body assembly line, pretreatment such as application of a primer or an adhesive is performed on the window glass mounting frame of the vehicle body. For example, the application of the primer to the window glass mounting frame portion is automatically performed by a primer application robot installed in a vehicle body pretreatment station provided in the vehicle body assembly line. When the operation of the primer coating robot is performed in such a vehicle body preprocessing station, the actual operation of the vehicle body sequentially loaded into the vehicle body preprocessing station by the vehicle body conveyor is performed in a vehicle stopping area provided in the vehicle body preprocessing station. Is required to be detected, and information on the detected vehicle position needs to be supplied to an operation control unit of the primer coating robot.

Therefore, the detection of the position of the vehicle body in the vehicle body stop area provided in the vehicle body preprocessing station of the vehicle body assembly line,
There has been proposed a method of optically using an imaging device such as a video camera. When an optical detection method for a vehicle body position in which such an imaging device is used is performed, for example, a part of a window glass mounting frame portion of a vehicle body stopped in a vehicle body preprocessing station is provided with a line light source. Light is emitted to form a line light image, and the line light image on a part of the window glass mounting frame is imaged by an image pickup device, and the line light image is taken from the image pickup device in accordance with the line light image on a part of the window glass mounting frame. For example, the position of the edge in a part of the window glass mounting frame is specified based on the image signal from the imaging device. Then, the position of the edge in a part of the window glass mounting frame portion is specified at a plurality of positions in the window glass mounting frame portion, and based on the specified position of each edge, the edge is stopped in the vehicle body preprocessing station. The detected vehicle body position is detected, and vehicle body position information is obtained.

(Problems to be Solved by the Invention) However, as described above, in order to detect the position of the vehicle body stopped in the vehicle body pretreatment station, a line light image is formed on the window glass mounting frame portion of the vehicle body. In the case where the position of the edge of the window glass mounting frame is specified based on the image signal obtained and the image signal obtained thereby, the position of the edge of the window glass mounting frame is specified. There is a problem that the accuracy depends on the paint color of the vehicle body.

That is, the vehicle body is assumed to have different external light reflectance according to the paint color thereof. Therefore, the linear light image obtained on the window glass mounting frame portion of the vehicle body has a constant light projection amount from the line light source. Even if it is at the base, it will take different forms depending on the paint color of the vehicle body. Accordingly, an image signal obtained by capturing a line light image formed on the window glass mounting frame portion is also different depending on the paint color of the vehicle body, and is supplied to the image monitor. When a playback image is to be obtained on an image monitor, for example,
Under the condition that the lightness of the paint color of the vehicle body is relatively low, the reflectance of the window glass mounting frame portion with respect to the light from the line light source is relatively low, and FIG.
As shown in the figure, while the reproduced image ID of the line light image in the window glass mounting frame portion can be clearly obtained on the image monitor, while the paint color of the vehicle body is assumed to be relatively high in brightness, the window glass The reflectance of the mounting frame portion with respect to the light from the linear light source is relatively high, and the third
As shown in FIG. B, there is a possibility that the reproduced image IL of the line light image in the window glass mounting frame on the image monitor may be in a state in which “blurring” due to halation or the like has occurred. In such a state, under the condition that the lightness of the paint color of the vehicle body is relatively low, the end PX of the reproduced image ID on the image monitor shown in FIG. It will be shown correctly, and based on the image signal obtained by capturing the line light image formed on the window glass mounting frame portion, the position of the edge in the window glass mounting frame portion will be specified with high accuracy, Under the condition that the lightness of the paint color of the vehicle body is relatively high, if the end portion PX ′ of the reproduced image IL on the image monitor shown in FIG. 3B correctly indicates the edge of the window glass mounting frame portion. Therefore, the edge of the window glass mounting frame portion is formed based on an image signal obtained by capturing a line light image formed on the window glass mounting frame portion. So that the location of a particular from being as less accurate.

In order to avoid such inconvenience that occurs when the paint color of the vehicle body is relatively high in brightness, the amount of light emitted from the line light source is reduced, and a line light image formed on the window glass mounting frame portion is captured. When the reproduced image signal is supplied to the image monitor and the reproduced image is obtained on the image monitor, the window glass is displayed on the image monitor under the condition that the paint color of the vehicle body is relatively high in brightness. When the reproduction image of the line light image in the mounting frame portion is set so as to be clearly obtained, the line light formed on the window glass mounting frame portion is provided under the condition that the paint color of the vehicle body is relatively low in brightness. There is a problem in that the amount of light in the image is insufficient, and it is difficult to form an image signal by capturing the image.

In view of such a point, the present invention includes a line light image forming a line light image on a part of a vehicle body and an image pickup means for obtaining an image signal by picking up a line light image formed on a part of the vehicle body; In detecting the position of the vehicle body based on the image signal obtained from the camera, the image signal obtained from the imaging means forms a position detection output that accurately represents the position of the vehicle body based on the image signal regardless of the paint color of the vehicle body. It is an object of the present invention to provide a position detecting device.

(Means and Actions for Solving the Problems) In order to achieve the above object, a position detecting device according to the present invention irradiates a predetermined portion of a vehicle body carried into a vehicle body assembly line to form a line light image. A light source, an imaging unit that captures a line light image formed on a predetermined portion of the vehicle body to obtain an image signal, and an image signal obtained from the imaging unit are supplied.
Control means for obtaining a position detection output representing the position of the vehicle body based on the image signal, and further, according to production management control for the vehicle body assembly line, paint color information for transmitting a paint color information signal corresponding to the vehicle body paint color A signal transmitting means is provided, and a control means is supplied with a coating color information signal from the coating color information signal transmitting means, and changes an irradiation light amount of a line light source or an imaging light receiving amount of an imaging means according to the coating color information signal. The light amount control is also performed and configured.

(Operation) In the position detecting device according to the present invention configured as described above, the control means controls the irradiation light amount of the line light source or the imaging light reception amount of the imaging means, for example, from the painting color information signal transmitting means. Increase when the paint color information signal indicates that the paint color of the vehicle body is relatively low in brightness, and when the paint color information signal from the paint color information signal sending means indicates that the paint color of the vehicle body is relatively high in brightness, Is controlled to decrease the value when Accordingly, when the image signal obtained from the imaging means is supplied to the image monitor, regardless of whether the painted color of the vehicle body is relatively low in brightness or relatively high in brightness, This is appropriate so that a reproduced image of a linear light image formed on a predetermined portion of the vehicle body can be clearly obtained on the image monitor. In addition, when the control unit performs the light amount control for changing the irradiation light amount of the line light source or the imaging light reception amount of the imaging unit, the vehicle body is carried in without newly providing equipment for causing the control unit to perform the light amount control. The paint color information transmitting means for transmitting the paint color information signal according to the production management control for the vehicle body assembly line is used, that is, the existing equipment is used, and the control means is required for the light amount control performed by the control means. A paint color information signal is easily supplied. Therefore, a position detection output that accurately represents the position of the vehicle body is formed in the control unit based on the image signal obtained from the imaging unit without causing a rise in manufacturing cost due to the introduction of new equipment.

(Embodiment) FIG. 2 shows a state in which an example of a position detecting device according to the present invention is installed in a vehicle body pre-processing station in a vehicle body assembly line. Are sequentially carried in intermittently.

In FIG. 2, a vehicle body 1 is carried into a vehicle body pre-processing station STA while being mounted on a bogie 4 that slides on a rail 3 disposed along a vehicle body assembly line. The vehicle body 1 is stopped at a vehicle stop area. Window glass attachment frames 9 and 10 forming openings 6 and 7 are provided on the front side and the rear side of the vehicle body 1, respectively.

In the vehicle body pretreatment station STA, for example, two front robots and two rear robots 11A and 11B, which are not shown, are provided for applying a primer. Perform primer application work on the left and right halves of the window glass mounting frame 9 in the vehicle body 1 carried into the vehicle body pre-processing station STA, respectively.
1B also includes a window glass mounting frame 10 in the vehicle body 1 respectively.
The primer application operation is performed on the left half and the right half. Both the rear robots 11A and 11B
The teaching playback type articulated robot has a similar configuration.
Is swung up and down, left and right, and back and forth with respect to the base 15 fixed to the base 14,
A wrist 16 provided at the distal end of the arm 13 is rotatable or swingable with respect to the arm 13. And, in the list 16 in each of the rear robots 11A and 11B,
In addition to the primer nozzle (not shown),
Video cameras 19 and 20 each provided with an optical filter constituting an imaging unit are attached, and in addition, for example, light having a wavelength band of about 780 to 837 m is irradiated, Line light sources 21 and 22 for forming images are respectively mounted.

The operations of the rear robots 11A and 11B are controlled by the robot control unit 30, and the robot control unit 30 controls the multi-function control unit 35 with the image monitor 35A.
Electrical connection with the Then, the multi-function control unit 35 further includes video cameras 19 and 20 provided on the rear robots 11A and 11B, and the line light sources 21 and
There are electrical connections with each of the 22.

The two front robots are also the rear robots 11
A teaching playback type articulated robot having the same configuration as A and 11B, each of which has a video camera and a line light image in addition to the primer nozzle, similarly to the rear robots 11A and 11B. These operations are controlled by a robot control unit corresponding to the robot control unit 30, and a video camera and a line light source attached to each front robot are connected to the multi-function control unit 35. The electrical connection with the corresponding multi-function control unit is established.

FIG. 1 shows an interconnection relationship between the robot control unit 30 and the multi-function control unit 35, and a connection relationship between them and each operation element. In FIG. 1, a multi-function control unit 35 includes a paint color information transmitting unit 40 provided in a production control central control unit for a vehicle body assembly line. The paint color data Dc is supplied. That is, the multi-function control unit 35 constitutes a production management central control unit that performs production management control on the vehicle body assembly line, and communicates with the paint color information transmission unit 40 that transmits the paint color data Dc according to the production management control. Connection is made, and the paint color information sending section
The paint color data Dc from 40 is supplied. Then, the multi-function control unit 35, in accordance with the coating color data Dc obtained from the coating color information sending unit 40, in order to control the irradiation light amount of the line light sources 21 and 22 attached to the rear robots 11A and 11B, respectively. Control signal Ca is applied to line light sources 21 and 22.
And Cb, respectively, and image signals Va and Vb obtained from the video cameras 19 and 20 attached to the rear robots 11A and 11B, respectively, are supplied,
Based on each of the image signals Va and Vb, a position signal Sp representing the position of the vehicle stopped in the vehicle stop area in the vehicle preprocessing station STA is formed, and is supplied to the robot control unit 30. Robot control unit 30
Forms robot control signals Cra and Crb that are modified in accordance with the position signal Sp supplied from the multi-function control unit 35, and supplies them to the rear robots 11A and 11B, respectively.

Under such circumstances, video cameras 19 and 20 attached to the rear robots 11A and 11B, respectively, and line light sources 21 and
The components including the multi-function control unit 35, the image monitor 35A, and the paint color information transmitting unit 40 form an example of the position detection device according to the present invention.

Under such a configuration, when the vehicle body 1 is carried into the vehicle body pre-processing station STA and is stopped in the vehicle body stop area provided there, and the state as shown in FIG. 2 is taken, The robot control unit 30 is the rear robot
Robot control signal Cra that causes 11A and 11B to perform initial operation
And Crb, respectively. As a result, the rear robot 1
1A and 11B are operated, the video camera 19 and the line light source 21 attached to the rear robot 11A, and the rear robot
Video camera 20 and line light source 22 attached to 11B,
A predetermined position is set with respect to the vehicle body stop area in the vehicle body preprocessing station STA. As a result, the second
In the example shown in the figure, a video camera 19 and a line light source
21 and the video camera 20 and the line light source 22 are respectively connected to the portions QA1 and QA2 of the windshield mounting frame 10 of the vehicle body 1.
At a predetermined separation distance.

Then, the line light source 21 irradiates the portion QA1 in the window glass mounting frame portion 10 to form a line light image intersecting the edge on the portion QA1, and the video camera 19 operates in the window glass mounting frame portion 10. The linear light image formed on the portion QA1 is imaged, an image signal Va is generated, and the image signal Va is supplied to the multi-function control unit 35.
Irradiates the portion QA2 in the window glass mounting frame portion 10 to form a line light image crossing the edge on the portion QA2, and the video camera 20 is formed on the portion QA2 in the window glass mounting frame portion 10. A state is assumed in which the obtained line light image is captured, an image signal Vb is generated, and the image signal Vb is supplied to the multi-function control unit 35.

In such a case, the multi-function control unit 35 is supplied with the paint color data Dc representing the paint color of the vehicle body 1 from the paint color information sending unit 40, and the multi-function control unit 35 performs the processing based on the paint color data Dc. To form control signals Ca and Cb, and supply them to the line light sources 21 and 22, respectively, so that the irradiation light amounts of the line light sources 21 and 22 are relatively low or the paint color of the vehicle body 1 represented by the paint color data Dc. Control is performed such that the brightness is relatively large when the vehicle has lightness, and relatively low when the paint color of the vehicle body 1 represented by the paint color data Dc has relatively high brightness. Thereby, the control signals Ca and
In each of the line light sources 21 and 22 to which Cb was respectively supplied,
The irradiation light amount becomes smaller as the paint color of the vehicle body 1 has a higher reflectance with respect to the light from each of the linear light sources 21 and 22.

Under the control of the irradiation light amount of each of the line light sources 21 and 22 in this manner, the video light sources are obtained from the video cameras 19 and 20, respectively.
The multifunctional control unit 35 to which the image signals Va and Vb corresponding to the line light image on the portion QA1 and the line light image on the portion QA2 in the window glass mounting frame 10 are represented by the image signal Va, Partial QA in mounting frame 10
On the basis of one end of the line light image on 1, the position data representing the position of the edge in the portion QA1 is obtained as a position detection output, and the line on the portion QA2 in the window glass mounting frame 10 represented by the image signal Vb. Based on one end of the light image, position data representing the position of the edge in the portion QA2 is obtained as a position detection output. Further, the multi-function control unit 35 forms display image signals Va ′ and Vb ′ based on the image signals Va and Vb, and displays them on the image monitor 35A.
To the image monitor 35A and the window glass mounting frame 1
A reproduced image of the line light image in each of the portions QA1 and QA2 at 0 is displayed.

At this time, the irradiation light amount of each of the line light sources 21 and 22 is
Are controlled in accordance with the paint color of the camera, the image signals Va obtained from the video cameras 19 and 20, respectively.
And Vb are image monitors regardless of the paint color of the vehicle body 1.
Reproduced images of line light images in each of the portions QA1 and QA2 in the window glass mounting frame portion 10 displayed at 35A are considered to be appropriate and will be obtained as clear images, and accordingly, each obtained based on them The position data is a partial QA1 and QA2 in the window glass mounting frame 10.
Are appropriately represented.

Next, the command signal Cr is supplied from the multi-function control unit 35 to the robot control unit 30, and in response thereto, the robot control unit 30 supplies the robot control signals Cra and Crb to the rear robots 11A and 11B, respectively. As a result, the rear robots 11A and 11B operate, and the rear robot 11A
Video camera 19 and line light source 21 attached to
The video camera 20 and the line light source 22 attached to the rear robot 11B are respectively connected to the vehicle body 1 as shown in FIG.
QB1 and QB2 in the window frame 10
And a next position set in advance, which faces each other at a predetermined separation distance. Then, the video cameras 19 and 20, the line light sources 21 and 22, the multi-function control unit 35, and the image monitor 35A, the same operation as in the case of the above-mentioned portion QA1 and QA2 in the window glass mounting frame 10 is performed, In the multi-function control unit 35,
Position data representing the position of the edge in each of the parts QB1 and QB2 in the window glass mounting frame 10 is obtained as a position detection output, and the image monitor 35A displays the portions QB1 and QB2 in the window glass mounting frame 10.
The reproduced image of the line light image in each of the above is displayed.

Subsequently, a command signal Cr is further supplied from the multi-function control unit 35 to the robot control unit 30, and the robot control unit 30 responds accordingly to the rear robots 11A and 1A.
The robot control signals Cra and Crb are supplied to 1B, respectively. Thereby, the rear robots 11A and 11B operate, and the video camera 19 and the line light source 21 attached to the rear robot 11A, and the video camera 20 and the line light source 22 attached to the rear robot 11B, respectively, As shown in FIG. 2, a portion of the vehicle body 1 in the window glass mounting frame portion 10.
The QC1 and the QC2 are assumed to face the QC1 and the QC2 with a predetermined separation distance, and assume a next position set in advance.
Then, the video cameras 19 and 20, the line light sources 21 and 22, the multi-function control unit 35, and the image monitor 35A, the same operation as in the case of the above-mentioned portion QA1 and QA2 in the window glass mounting frame 10 is performed, Multi-function control unit 35
In the part QC1 in the window glass mounting frame 10
The position data representing the position of the edge in each of QC2 and QC2 is obtained as a position detection output, and the reproduced image of the line light image in each of the portions QC1 and QC2 in the window glass mounting frame 10 is displayed on the image monitor 35A. .

Thus, in the multi-function control unit 35, the portions QA1, QA2, QB in the window glass mounting frame 10 of the vehicle body 1
When the position data representing the position of the edge in each of 1, QB2, QC1 and QC2 is obtained, the multi-function control unit 35
Based on the position data, a position signal Sp representing the position of the rear side portion of the vehicle body 1 is formed and supplied to the robot control unit 30, and the robot control unit 30 stores the position signal Sp. Such a position signal Sp also appropriately represents the position of the rear portion of the vehicle body 1 with high accuracy regardless of the paint color of the vehicle body 1.

As described above, the position of the rear side portion of the vehicle body 1 is detected, and the position signal Sp obtained as a result is subsequently used for operations on the vehicle body 1 by the rear robots 11A and 11B.
For example, when a primer application operation is performed on the window glass mounting frame portion 10, the robot control unit 30
Is used when the robot control signals Cra and Crb are formed by

The detection of the position of the front side portion of the vehicle body 1 is also performed by supplying the video camera and the line light source attached to each of the two front side robots and the image signal from the video camera and irradiating the line light source. With a configuration including a multi-function control unit that supplies a control signal to perform light quantity control, the detection is performed similarly to the detection of the position of the rear side portion of the vehicle body 1.

Further, in the above-described example, the irradiation light amounts of the linear light sources 21 and 22 are controlled by the multifunctional control unit 35 in accordance with the paint color of the vehicle body 1 carried into the vehicle body preprocessing station STA. However, instead of the irradiation light amount of each of the linear light sources 21 and 22, the amount of light received by each of the video cameras 19 and 21 is changed so that the paint color of the vehicle body 1 carried into the vehicle body preprocessing station STA is relatively low. Is controlled to be relatively large when the video camera 19 and the video camera 19 and the paint color of the vehicle body 1 has a relatively high brightness.
The amount of light received by each of the imaging light sources 20 may be made smaller as the paint color of the vehicle body 1 has a higher reflectance with respect to the light from each of the linear light sources 21 and 22.

(Effects of the Invention) As is clear from the above description, according to the position detection device of the present invention, a line light source for forming a line light image of a vehicle body and a line light image formed on the vehicle body are imaged to generate an image signal. When the detection of the position of the vehicle body based on the image signal obtained from the imaging means is performed by the control means, the control means determines the irradiation light amount of the line light source or the imaging light reception amount of the imaging means. For example, when the paint color information signal corresponding to the device color of the vehicle body indicates that the paint color is relatively low in brightness, the value is increased, and the paint color information signal is that the paint color is relatively high in brightness. When it is shown that there is, by controlling to reduce it,
When the image signal obtained from the imaging means is supplied to the image monitor, regardless of whether the paint color on the vehicle body has a relatively low brightness or a relatively high brightness, the image signal is displayed on the image monitor. Thus, a reproduced image of the linear light image formed on the object to be detected is obtained as an appropriate one so that a clear image can be obtained. Further, the control for changing the irradiation light amount of the line light source or the imaging light receiving amount of the imaging means by the control means is performed by controlling the coating color information signal transmitted by the coating color information transmission means in accordance with the production management control for the vehicle body assembly line into which the vehicle is loaded. It is utilized and performed, and a situation that causes a rise in manufacturing cost is avoided. Therefore, under the condition that a rise in manufacturing cost is avoided, the control means obtains a position detection output that accurately represents the position of the vehicle body based on the image signal obtained from the imaging means regardless of the paint color of the vehicle body. Can be.

[Brief description of the drawings]

FIG. 1 is a block connection diagram showing an example of a position detecting device according to the present invention together with a robot control system to which it is applied, and FIG. FIGS. 3A and 3B are schematic diagrams showing the configuration together with the station, and FIGS. 3A and 3B are views for explaining a conventional optical position detecting device. In the figure, 1 is a vehicle body, 9 and 10 are window glass mounting frames,
11A and 11B are rear robots, 19 and 20 are video cameras, 21 and 22 are linear light sources, 30 is a robot control unit, 35
Is a multi-function control unit, 40 is a paint color information sending section, STA is a body pre-processing station, QA1, QA2, QB1, QB2, QC1, and QC2.
Denotes a window glass mounting frame portion 10.

Claims (3)

(57) [Claims] 1. A line light source for irradiating a predetermined portion of a vehicle body carried into a vehicle body assembly line to form a linear light image, and capturing an image signal by capturing the line light image formed on a predetermined portion of the vehicle body. Imaging means for obtaining; a paint color information transmitting means for transmitting a paint color information signal corresponding to a paint color for the vehicle body according to production management control for the vehicle body assembly line; In addition to performing light amount control for changing the irradiation light amount of the line light source or the imaging light reception amount of the imaging unit according to the information signal, an image signal obtained from the imaging unit is supplied, and the position of the vehicle body is determined based on the image signal. And a control means for obtaining a position detection output representing the following. 2. The control means according to claim 1, wherein said control means controls said line light source to emit a relatively large amount of light when said paint color information signal sent from said paint color information sending means has a relatively low lightness. 2. A light amount control for making the irradiation light amount of the line light source relatively small when a paint color of the vehicle body represented by the paint color information signal has relatively high brightness. Position detection device. 3. The control means controls the amount of light received by the image pickup means as the reflectivity of the paint color information signal transmitted from the paint color information transmission means to the light from the linear light source of the paint color of the vehicle body increases. 2. The position detecting device according to claim 1, wherein the light amount is controlled to be small.