JPH0872764A - Production line controller - Google Patents

Abstract

PURPOSE: To provide cooperation between control performed by a robot controller and synchronous follow-up control for synchronously moving a robot following a workpiece while preventing an increase in the operational processing load on the robot controller. CONSTITUTION: At a painted surface testing station in an automobile manufacturing plant such components are provided as a conveyor 6, a robot 7, a travel guiding path 8 for moving the robot 7, a drillig shaft 8a, a robot controller, a main controller for making driving and position detection control of the conveyor 6 making, movement drive control of the robot 7 and making movement postion detection control of the robot 7 and by moving the robot 7 synchronously with a workpiece 1, inspection is made by the robot 7 and any detective portion is polished. For each working zone, the robot 7 is synchronously moved after being set in a teaching position after the robot 7 reaches its limit position, inspection and polishing are continued by correctig teaching information.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a production line control device, and more particularly to a production line control device for performing a work with high accuracy while moving a robot synchronously following a work being conveyed.

[0002]

2. Description of the Related Art Conventionally, in an automobile manufacturing plant, a conveyor is provided to convey a work along a production line for processing, assembling and inspecting, and in each process of the production line, a plurality of teaching / playback devices are provided near the line. A work robot of a system is provided, and while the transfer of the work and the stop of the transfer are repeated, the work being stopped is performed by these robots. In this way, when the conveyance of the work and the stop of the conveyance are repeated, it is difficult to control the position of the work accurately, which becomes a factor of lowering the accuracy of processing and assembly, and a buffer station or the like is also required, which lengthens the production line. Become.

In view of this, recently, a technique has been proposed in which a robot is moved synchronously with respect to the work while the work is being carried, and the work is conveyed at a microscopic microscopic speed. Because of the fluctuation, when machining or assembling is performed with high accuracy, the load of arithmetic processing for synchronously moving the robot with respect to the work increases. Then, in the case of synchronously moving the robot as described above, conventionally, a work transfer control means for performing the transfer control of the work and its position detection control is provided separately from the robot controller, and the movement control of the robot and its Generally, the robot controller is responsible for the movement position detection control.

As described above, as a synchronous working device for synchronously following the work with the parts assembly automatic machine, the fair work 1-
No. 13025 discloses a transfer device for transferring a work,
A traveling carriage that travels along the transport device, and an engagement piece that is provided on the traveling carriage and that engages the transport device with a load;
There has been proposed a vehicle including a speed adjusting drive unit for synchronously moving traveling vehicles via the engagement pieces.

[0005]

While transporting a work,
Regarding a control device for a production line that performs work while synchronously moving a work robot with respect to a work, in the related art, a work transfer control means that performs work transfer control and position detection control is called a robot controller. Since the robot controller is separately provided and the robot controller is responsible for the movement drive control of the robot and the movement position detection control thereof, the control of the robot by the robot controller and the control of synchronously moving the robot following the work are performed as follows. However, there is a problem that it becomes difficult to make the cooperation easily and the arithmetic processing load of the robot controller increases.

[0006] When the work is conveyed to a predetermined process of the production line and the robot starts the work, the positional relationship between the work and the robot is different from the positional relationship when the robot is taught. Therefore, the robot is stored in the robot controller. The load on the robot controller such as the arithmetic processing for correcting the teaching information and the arithmetic processing for synchronously following the conveyed work by the robot increases.

Therefore, when starting the work with the robot, it is conceivable to execute teaching position adjustment control for controlling the position of the robot with respect to the work so as to have a positional relationship at the time of teaching. The load of arithmetic processing for synchronously following the robot to the momentary position remains on the robot controller side. Moreover, when one robot shares the work in a plurality of work zones, the teaching position for each work zone is often different, so it is necessary to perform the teaching position adjustment control each time the work in each work zone is started. Therefore, the processing load for that is also generated in the robot controller.

Further, when the robot reaches the movement limit position before the downstream end of the predetermined process, it is necessary to stop the synchronous follow-up movement of the robot. At this point, when the work by the robot is stopped, In addition, the production line becomes longer by that much, and when the work by the robot is continued, the correction processing of the teaching information is necessary, but the load of the correction processing of the teaching information is also generated in the robot controller. An object of the present invention is to achieve cooperation between control by the robot controller and robot synchronous follow-up control while preventing an increase in arithmetic processing load on the robot controller.

[0009]

A production line control apparatus according to a first aspect of the present invention, as shown in the functional block diagram of FIG. 1, relates to a work transfer means for transferring a work and a work transferred by the work transfer means. In a production line control device equipped with a robot for performing a predetermined work by means of a robot and a robot movement drive means capable of moving the robot along a work transfer path, the position in the transfer direction of the work transferred by the work transfer means is detected. Work position detecting means, a robot position detecting means for detecting the position of the robot which is driven to move in the work conveying direction by the robot movement driving means, a robot control means for controlling the robot, and a robot during movement of the robot. The work position detection means and the synchronization control means for controlling the robot movement drive means so as to move in synchronization with the work. Using the position of the robot detected by the position and the robot position detecting unit of the workpiece to be known, but with the control by the robot control unit, and a cooperative control means to coordinate and control by the synchronization control means.

The robot may be a robot that shares a plurality of work zones of a work and performs a work including a playback-type work based on teaching information taught in each zone (claim 1). Claim 2) dependent on. The cooperative control means may be configured to control the robot movement driving means via the synchronous control means so that the robot has a positional relationship with respect to the work at the time of starting work in each work zone. (Claim 3 dependent on Claim 2). The cooperative control means, when the position of the robot detected by the robot position detection means reaches the limit position on the downstream side in the work transfer direction,
The teaching information correcting means may be configured to calculate a correction amount for correcting the teaching information based on the position of the work detected by the work position detecting means and the limit position, and output the calculated correction amount to the robot control means. Claim 4) dependent on claim 3.

[0011]

In the production line control apparatus according to the present invention, the position in the carrying direction of the work carried by the work carrying means is detected by the work position detecting means,
Further, a robot that performs a predetermined work on the conveyed work can be moved along the work conveyance path by the robot movement drive means, and the position of the robot that is driven to move in the work conveyance direction is the robot position. It is detected by the detection means. The robot control means controls the robot, the synchronous control means controls the robot movement driving means so that the robot synchronously follows the work being conveyed, and the cooperative control means is detected by the work position detecting means. By using the position of the work and the position of the robot detected by the robot position detection means, the control by the robot control means and the control by the synchronous control means are coordinated.

As described above, the work transfer means and the work position detection means are provided, and the robot movement drive means is provided separately from the robot control means for controlling the robot so that the robot moves synchronously following the work being transferred. Since the synchronous control means for controlling is provided and the cooperative control means for coordinating the control by the robot control means and the control by the synchronous control means is provided, the arithmetic processing load of the robot control means increases in order to move the robot synchronously following the work. The robot control means and the control by the synchronous control means in cooperation with each other, and the robot can perform work with high accuracy on the work being conveyed,
And so on.

In the production line control apparatus according to the present invention, the robot divides a plurality of work zones of a work and performs a work including a playback type work based on teaching information taught in each zone. However, the coordinated control means can easily execute control such that the robot is positioned at the teaching position with respect to the work being conveyed.

In the production line control apparatus according to the third aspect of the present invention, the cooperative control means is provided via the synchronous control means so that the robot has a positional relationship with the work at the time of teaching at the start of work in each work zone. Controls the robot movement drive means. Similarly to claim 2, the robot can be moved synchronously with respect to the workpiece in a positional relationship at the time of teaching without increasing the calculation processing load of the robot controller, and as a result, the robot controller can teach information. Since it can be utilized without correcting, the calculation processing load of the robot control means is reduced.

In the production line control device according to the fourth aspect of the present invention, the teaching information correction means provided in the cooperative control means has the robot position detected by the robot position detection means reach a limit position on the downstream side in the work transfer direction. In this case, a correction amount for correcting the teaching information is calculated based on the position of the work and the limit position detected by the work position detection means, and the calculated correction amount is output to the robot control means. Therefore, even when the robot reaches the limit position and stops moving, the robot controller is supplied with a correction amount for correcting the teaching information without increasing the calculation processing load of the robot controller, and the teaching information is effectively utilized. Work can be continued.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. This embodiment is an example in which the present invention is applied to a coating surface inspection apparatus for detecting coating defects on the surface of an automobile body after top coating in an automobile manufacturing plant.
As shown in FIG. 2, the coating surface inspection station KS provided on the downstream side of the coating process is provided with a coating surface inspection device described below.
A coating defect on the surface of the automobile body 1 is detected, the detected defective portion is polished, and then the automobile body 1 is transported to a subsequent process, and repair coating is performed on the surface defective portion. In the following description, the front side (left side in FIG. 1) of the automobile body 1 in the transport direction is referred to as the front, and the left-right direction facing the front is referred to as the left-right direction.

The coating surface inspection device will be described.
As shown in FIG. 2, the coating surface inspection station KS is
It is covered with the ceiling wall 2, the left and right side walls 3 and 4, and the front and rear walls with openings on both front and rear sides, and is a trolley-type conveyor 6 for mounting the work on the trolley 5 and transporting it to the coating surface inspection station KS. Are provided so as to pass through in the front-rear direction, and two light irradiation devices (not shown) for irradiating illumination light (inspection light) on the upper surface and left and right side surfaces of the work are installed on the ceiling wall 2 The inspection robots 7 (first inspection robot 7a, second inspection robot 7b, first inspection robot 7a, second inspection robot 7b, first inspection robot 7a, second inspection robot 7b, which are provided on each of the side walls 2 and 4 and include four articulated robots for inspecting the coating surface are internally provided. 3 inspection robot 7c, 4th inspection robot 7
Two d) are provided on each of the left and right sides.

The first and second inspection robots 7a and 7b
Is guided and supported so as to be movable in the transport direction of the conveyor 6 along a travel guide path 8 on the left side of the conveyor 6, and a ball screw shaft 8a (see FIG. 3) is disposed in the travel guide path 8.
The first and second inspection robots 7a and 7b are respectively provided with ball screw nuts screwed onto the ball screw shaft 8a and driven by the electric motor 9. The third and fourth inspection robots 7c and 7d are guided and supported so as to be movable in the transport direction of the conveyor 6 along a traveling guide path 8 on the right side of the conveyor 6, and the traveling guide path 8 has a ball screw shaft 8a (see FIG. 3) is provided, and the third and fourth inspection robots 7c and 7d are
Ball screw nuts that are screwed onto the ball screw shaft 8a and driven by the motor 9 are provided.

A CCD is provided in the hand portion of each inspection robot 7.
A camera 11 and a polishing grindstone 12 for polishing a coating defect portion,
A marker 13 for marking a coating defect portion that cannot be polished within a predetermined takt time is provided. The four inspection robots 7 are each assigned with an inspection area in which the surface of the work is divided into four equal parts. For example, the first inspection robot 7
As shown in FIG. 10, the first inspection area shared by a is a first zone a1 on the left half of the Bonnent, a second zone a2 on the left front fender, and a third zone a3 on the left front half of the roof. And the fourth zone a4 of the left front door. The second inspection area shared by the second inspection robot 7b is, as shown in FIG. 10, the first inspection area in the left half of the roof.
Zone b1, second zone b2 on the left side center pillar and rear door, and third zone b3 on the left half of the trunk lid.
And the fourth zone b4 of the left rear fender. The third inspection area shared by the third inspection robot 7c is in a left-right symmetrical relationship with the first inspection area, and the fourth inspection area shared by the fourth inspection robot 7d is a second inspection area and a left-right object. Have a relationship.

Next, the control system of the coating surface inspection apparatus described above will be described. As shown in FIG. 4, a main control device 20 for controlling the entire coating surface inspection device is provided, and the main control device 20 includes a light irradiation device control unit for driving and controlling an operation panel 22 and six light source lamps 23. 24,
Work carry-in detection switch 25 for detecting work carry-in and work carry-out detection switch 26 for detecting work carry-out
(See FIG. 3), a conveyor motor 27 that drives the conveyor 6 for transporting the work, and rotary encoders 28 and 4 thereof.
A movement drive motor 9 for moving the inspection robots 7a to 7d and their rotary encoders 10, a robot controller 30 for the four inspection robots 7a to 7d, and a camera controller 31 connected to each robot controller 30 and controlling a CCD camera 32. Etc. are electrically connected.

The main control unit 20 receives the production control information (information such as the model of the work carried in to the coating surface inspection station KS, the coating color, etc.) transmitted from the host computer 21 for the production control of the factory, and receives the information. Perform a paint surface inspection based on production control information. The robot controller 30 controls the polishing motor 32 that drives the polishing wheel 12 and the valve 33 that opens and closes the liquid passage used by the marker 13.

The main controller 20 contains an input / output interface, a microcomputer, a plurality of counter circuits, a plurality of drive circuits, etc., and the microcomputer includes a coating process including the processes and controls listed below. A control program for surface inspection control is stored. (1)
Work loading / unloading detection processing, (2) Work transportation drive control, (3)
Work transfer position detection control, (4) 1st to 4th robot 7a
~ 7d movement drive control, (5) 1st ~ 4th robot 7a ~
7d moving position detection control, (6) 4 CCD cameras 11
Image data analysis / painting defect detection processing, coating defect position and grade calculation processing in (7) Processing to supply the coating defect position and grade to the corresponding robot controller.

Regarding the work loading / unloading detection process (1), the loading of the work is detected based on the detection signal from the work loading detection switch 25, and the work loading is detected based on the detection signal from the work loading detection switch 26. Export is detected. The work transfer drive control in (2) above is performed by the conveyor drive motor 27 so that the work is transferred at a constant low speed.
The work transfer position detection control of (3) above is a control for detecting the work transfer position by counting the pulse signals from the rotary encoder 28 that detects the rotation amount of the conveyor drive motor 27. , This is always done. The first to fourth robots 7a to 7d of (4) above
The movement drive control of each inspection robot 7 is performed so that each inspection robot 7 synchronously follows and moves in the same direction as the workpiece at the same speed.
The robot movement drive motor 27 is controlled to stop the robot movement drive motor 27 when each inspection robot 7 reaches a preset limit position on the downstream side in the transport direction (see FIG. 3). .

The first to fourth robots 7a to 7d of the above (5)
The moving position detection control of the four rotary encoders 10
This is a control for counting the pulse signals from the respective sensors and detecting the movement position of each inspection robot 7 in the transport direction, which is always executed. The image data analysis / painting defect detection processing, the painting defect position and grade calculation processing of the four CCD cameras 11 described in (6) above will be briefly described. When inspecting the coated surface of a work by this coating surface inspection device, the four inspection robots 7 are synchronously moved while the work is transported at a low speed, and the four inspection robots 7 are instructed based on a command from the main controller 20. The inspection robots 7 are controlled by the respective robot controllers 30 based on the teaching information previously taught, and the inspection is executed.

As shown in FIG. 11, the first inspection robot 7
a inspects the first zone a1, the first zone a1
A plurality of square-shaped imaging unit areas 29 (for example, 20
0 mm × 200 mm area), and the inspection is performed on these many imaging unit areas 29 in a predetermined teaching order.
In reality, the image is captured in a lap shape for a width of about 20 mm. The defect detection process of analyzing the image data from the CCD camera 11 and detecting the coating defect is executed, for example, in the same manner as the technique described in JP-A-5-322543.

The coordinate system XYZ of the coating surface inspection device
Is set as shown in FIGS. 3 and 11, the coating defect 29
The position of a is detected as, for example, the position in the coordinate system UVW with the origin of the center of the imaging unit area 29. The coating defect grade is a polishing grade classified into a plurality of stages according to the type and size of the coating defect. That is, in the process (6), the image data is analyzed to detect one or a plurality of coating defects in the imaging unit area 29, and the position and grade of these coating defects are calculated.

The robot controller 30 of each of the four inspection robots 7 has previously input and stored teaching information for inspecting a large number of image pickup unit areas 29 in the four zones of the inspection area to be shared in a predetermined order. There is. The teaching position of the inspection robot 7 with respect to the work at the time of performing this teaching is the first and second inspection robots 7.
In the case of a and 7b, it is as shown in FIG. 10, for example. The teaching positions of the third and fourth inspection robots 7c and 7d are symmetrical with the teaching positions of the first and second inspection robots 7a and 7b.

Each robot controller 30 moves the CCD camera 11 to a large number of image pickup unit areas 29 of each zone 29 in a predetermined order based on the teaching information of each zone 29, and the camera controller 31 and the CCD camera 11 are moved. Image data is supplied to the main controller 20 via the camera controller 31 every time the image is captured, and after the image capturing of each zone is completed, information on the position and grade of the coating defect is received from the main controller 20. , Based on the teaching information and the coating defect position, the polishing wheel 12 is sequentially moved to the coating defect position in the same order as when the image is taken, and the polishing motor 32 is driven based on a predetermined polishing control program. Perform polishing in a controlled manner.

Next, with respect to the outline of the coating surface inspection control executed by the main controller 20, referring to the flowcharts of FIGS. 5 to 9, an example in which the first inspection robot 7a inspects the first inspection area will be described. As described below. In the figure,
Si (i = 1, 2, 3, ...) Shows each step. As shown in FIG. 5, various signals and data are first read after the start of control (S1), and then the vehicle type is determined based on the information from the host computer 21 (S).
2). Next, the movement drive motor 2 of the first inspection robot 7a
7 is driven to move the first inspection robot 7a to the initial position (see FIG. 3) (S3). There is a switch (not shown) at the initial position, and it is confirmed that the initial position has been reached based on the switch signal.

Next, it is judged whether or not the detection signal of the work carry-in inspection switch 25 is ON (that is, whether the work has been carried in) (S4), and when the judgment is Yes, the work which is separately always detected is detected. The movement drive motor 27 is driven based on the vehicle type while taking the carrying position into consideration to move the first inspection robot 7a to the teaching position of the first zone a1 (the teaching position relative to the work) (S5). . Next, the drive motor 27 is driven to drive the first
The synchronous follow-up movement for moving the inspection robot 7a in the same direction at the same speed as the work is started (S6). In this way, since the first inspection robot 7a synchronously moves from the teaching position, the relative positional relationship between the workpiece and the first inspection robot 7a is maintained in the same positional relationship as when the teaching is performed. Therefore, the teaching for the first zone a1 is performed. The first zone a1 can be inspected while controlling the first inspection robot 7a based on the information.

Next, an inspection start command for the first zone a1 is output to the robot controller 30 (S
7) Next, the image data of each imaging unit area 29 is received from the camera controller 31, and the image data is analyzed to detect coating defects. The defect position for calculating the grade and the grade calculating process are executed, and the data is stored in the memory (S8). Next, in S9, it is determined whether or not the inspection of the first zone a1 is completed based on the signal from the robot controller 30. If the determination is No, S8 and S9 are repeated until the inspection is completed, and the determination is Yes. Then, in S10, the coating defect position information of the first zone a1 (including the number of the imaging unit area 29 and the position information of the defect in the area), the grade information of each defect,
A polishing start command for starting the polishing of the coating defect in the first zone a1 and the like are output to the robot controller 30. Then, in S11, it is determined whether or not the polishing of the first zone a1 is completed, and the determination is repeated until the determination becomes Yes, and when the determination becomes Yes, the process proceeds to S12 in FIG.

Since the teaching positions of the first zone a1 and the second zone a2 are common, the inspection of the second zone a2 can be started immediately after the polishing for the first zone a1 is completed. First, the second zone a2
An inspection start command for instructing the start of the inspection is output to the robot controller 30 (S12), and then, similarly to S8, the image data of each imaging unit area 29 is received from the camera controller 31, and the image data of the image data is received. Analysis / painting defect detection processing, defect position and grade calculation processing are executed, and the data is stored in the memory (S13). Next, it is determined whether or not the inspection of the second zone a2 is completed (S1
4) If the judgment is No, S13 and S14 are repeated until the inspection is completed. When the inspection of the second zone a2 is completed, in S15, the coating defect position information of the second zone a2, the grade information of each defect, the A polishing start command for starting the polishing of the coating defect in the second zone a2, etc. is output to the robot controller 30.

Then, in S16, it is determined whether or not the polishing of the second zone a2 is completed, and the determination is repeated until the determination becomes Yes. When the determination becomes Yes, in S17,
Similar to S5, the movement drive motor 27 is driven based on the vehicle type while taking the work transfer position into consideration, and the first inspection robot 7a is moved to the teaching position of the third zone a3 (the teaching position relative to the work). Move to.

Next, a command to start the inspection of the third zone a3 is output to the robot controller 30 (S
18) Next, similarly to S13, each imaging unit area 29
Receive the image data for each from the camera controller 31,
The analysis / painting defect detection processing of the image data, the defect position and grade calculation processing are executed, and the data is stored in the memory (S19). Next, it is determined whether or not the inspection of the third zone a3 is completed (S20). If the determination is No, S19 and S20 are repeated until the inspection is completed, and the third zone a3 is determined.
When the inspection is finished, in S21, the third zone a3
Of the coating defect position information, grade information of each defect, a polishing start command for starting polishing of the coating defect of the third zone a3, etc. are output to the robot controller 30. And S
In No. 22, it is determined whether or not the polishing of the third zone a3 is completed, and the determination is repeated until the determination becomes Yes, and the determination is Yes.
When s is reached, the process proceeds to S23 in FIG.

By the way, when there are many coating defects in the first to third zones a1 to a3, at the beginning of the inspection of the fourth zone a4 or during the inspection, or during polishing of the coating defects of the fourth zone a4, the first The inspection robot 7a may reach the downstream limit position (see FIG. 3), and the first inspection robot 7a may not be able to move synchronously with the work. In such a case, the remaining work is executed with the first inspection robot 7a stopped at the limit position. In this case, the first inspection robot 7a
It is necessary to correct the teaching information in consideration of the momentary advance amount of the work with respect to a.

Therefore, as shown in FIG. 7, first, the first inspection robot 7 is first detected based on the moving position of the first inspection robot 7a which is constantly detected and the set value corresponding to the limit position.
It is determined whether or not the movement position of a is the limit position (S23), and when the determination is Yes, the movement of the first inspection robot 7a is stopped (S24), and then the correction process for correcting the teaching information is started. (S25) Next, in S26, the flag Ft indicating that the correction process is activated is set to 1
After setting to, the process proceeds to S27. The teaching information correction processing will be described later.

On the other hand, if the determination in S23 is No, or S
After the step of 26, an inspection start command for starting the inspection of the fourth zone a4 is output to the robot controller 30 (S27), and then, similarly to S19, the image data of each imaging unit area 29 is captured by the camera. Upon reception from the controller 31, analysis / painting defect detection processing of the image data, defect position and grade calculation processing are executed, and the data is stored in the memory (S28). Next, it is determined whether or not the inspection of the fourth zone a4 is completed (S29). If the determination is No, S28 and S29 are repeated until the inspection is completed. When the inspection of the fourth zone a4 is completed, S35 of FIG. Move to. That is, if the determination in S29 is No, it is determined whether or not the flag Ft is 1 (S30), and in S26, the flag Ft.
If is already set, the process returns to S28. If the result of the determination in S30 is that the flag Ft has not been set, it is determined in S31 whether or not the moving position of the first inspection robot 7a is the limit position, as in S23.
If No, the process returns to S28.

On the other hand, when the determination in S31 is Yes, the movement of the first inspection robot 7a is stopped (S32), then the correction process for correcting the teaching information is started (S33), and then in S34, After setting the flag Ft to 1, the process proceeds to S28. Thus, while the first inspection robot 7a does not reach the limit position, the fourth zone a4 is activated without starting the teaching information correction process.
After the first inspection robot 7a reaches the limit position, the inspection of the fourth zone a4 is continued and the inspection of the fourth zone a4 is continued in a state where the teaching information correction processing is activated. When finished, S35 of FIG.
Move to.

In S35 of FIG. 8, as in S21, the robot is provided with the coating defect position information of the fourth zone a4, grade information of each defect, a polishing start command for starting polishing of the coating defect of the fourth zone a4, and the like. It is output to the controller 30, and then, in S36, it is determined whether or not the moving position of the first inspection robot 7a is the limit position. When the determination is No, it is determined whether or not the polishing of the fourth zone a4 is completed. (S37), if the determination is No, the process returns to S36. If the first inspection robot 7a does not reach the limit position, S
When 36 and S37 are repeated and the polishing of the fourth zone a4 is completed, this control ends. On the other hand, if the first inspection robot 7a reaches the limit position during the inspection, or if the first inspection robot 7a reaches the limit position during the polishing of the fourth zone a4, S36 Is judged as Ye
Therefore, the process proceeds to S38, where it is determined whether the flag Ft has been set. If the flag Ft has been set,
Since the teaching information correction process has already been started,
The process moves from S38 to S37.

However, when the flag Ft is not set, the movement of the first inspection robot 7a is stopped in S39, the teaching information correction process is started next (S40), and then the flag Ft is set to 1. And then S3
Move to 7. Thus, when the first inspection robot 7a does not reach the limit position, the polishing of the fourth zone a4 is executed without activating the teaching information correction process,
Further, after the first inspection robot 7a reaches the limit position, the polishing of the fourth zone a4 is continued and the fourth zone a4 is continued in the state where the teaching information correction processing is activated.
When the polishing of 1 is finished, this control is finished.

Next, the teaching information correction processing will be described. As shown in FIG. 9, when this correction process is started, first, the current movement position (xw) of the workpiece which is always detected is read (S50), and then S5.
1, the amount of work advance Δx with respect to the first inspection robot 7a is calculated as Δx = (xw−xe).
It should be noted that xe indicates the limit position (see FIG. 3) of the first inspection robot 7a. Next, in S52, each imaging teaching point [x, y, z] taught as a position for imaging each imaging unit area is set to [(x + Δx),
y, z] is output to the robot controller 30, and it is then determined whether or not the polishing of the fourth zone a4 is completed (S53). If the determination is No, S50
Return to step S50 and subsequent steps are repeated, and the determination in step S53 is Yes.
Then, this correction process ends.

In this way, after the teaching information correction process is started, the respective imaging teaching points [x, y, z] are taken into consideration by taking into consideration the progress amount Δx of the workpiece every moment.
Since it is corrected to [(x + Δx), y, z], the first inspection robot 7a reaches the limit position, stops the synchronous follow-up movement with respect to the workpiece, and the positional relationship of the first inspection robot 7a with respect to the workpiece is the positional relationship during teaching. Even if it is not, the inspection information and the polishing can be executed by effectively utilizing the teaching information.

With respect to the above correction, the first correction is made according to FIG.
A supplementary explanation will be given by taking the case of the zone a1 as an example. In the state where the first inspection robot 7a is positioned at the teaching position, the teaching point for controlling the robot arm to image a certain imaging unit area 29 is Pi. , The teaching point Pi moves to Pis when the work advances by Δxi with respect to the first inspection robot 7a. Teaching point Pi
The position of the teaching point Pis becomes [(x + Δxi), y, z] when the position of [x, y, z] is set. Therefore, the teaching information is corrected by correcting the teaching information as in the above correction process. It is possible to make effective use of the image capturing area 29 to capture an image of the image capturing unit area 29 in the same state as when teaching was performed.

The amount of advance of the work with respect to the first inspection robot 7a is further increased from the image pickup of a certain imaging unit area 29 to the polishing of the coating defect of the imaging unit area 29, but the position of the coating defect is increased. Is defined by a coordinate system UVW in which the center point of each imaging unit area 29 is the coordinate origin. Therefore, from the teaching information corrected by the amount of advance of the work at the time of polishing and the position information of the coating defect, It will be possible to determine the position of the coating defect.

Next, the operation of the coating surface inspection apparatus described above will be described. First, since the inspection and the polishing are executed while the work is being conveyed and the inspection robot 7 synchronously follows the work, an error factor caused by repeating the movement stop of the work and the subsequent movement start is eliminated. In addition to improving the accuracy of the inspection and polishing of coating defects, this coating surface inspection device is applied to the existing coating surface inspection station where the operator visually and manually inspects and polishes while transporting. be able to.

Each time the inspection of each zone is started, the inspection robot 7
Since the workpiece is moved to the teaching position and then moved synchronously, the positional relationship between the workpiece and the inspection robot 7 can be maintained in the same positional relationship as during the teaching, and the inspection / polishing can be executed. There is no need to make changes, and an increase in the load on the robot controller 30 can be avoided.

The movement control of the inspection robot 7 and the movement position detection control are performed not by the robot controller 30 but by the main controller 20, and the main controller 20 performs the work transfer control and the position detection control. Since it is configured to be performed, the control logic for controlling the position of the inspection robot 7 in relation to the position of the workpiece in the conveyance direction is significantly simplified. That is, control is performed to position the inspection robot 7 at the teaching position, and after the inspection robot 7 reaches the limit position, inspection and polishing are performed without stopping the movement of the work while the inspection robot 7 is stopped. In this case, the control of the teaching information correction process etc. has been remarkably simplified. Further, the main controller 20 causes the inspection robots 7a and 7b to interfere with each other and the inspection robots 7c and 7d.
When the control for checking so that mutual interference does not occur is also executed, the control logic of the mutual interference prevention control is also simplified.

As a result, after the inspection robot 7 reaches the limit position, the teaching information is effectively corrected by simply correcting the teaching information by the teaching information correction process of the simple logic. Since the inspection / polishing can be performed without stopping the movement of the work while the inspection robot 7 is stopped, the production line of the coating surface inspection station can be shortened.

In the above-described embodiment, when a minute speed change occurs in the work transfer speed due to various factors on the conveyor 6 side during the transfer of the work, the accuracy decrease due to the minute speed change is eliminated. Therefore, a contact member that exerts a pressing force on the work being conveyed is provided, and a work position detection unit that detects the position in the conveyance direction of the work based on the position of the contact member is provided. Based on the detected work position, the robot movement drive motor 2 is used to move the inspection robot 7 synchronously with the work.
7 may be configured to be controlled.

In the present embodiment, the case where the present invention is applied to the coating surface inspection device in the automobile manufacturing plant has been described as an example.
Other various production lines, in which various operations are performed on the work by the robot while the work is being conveyed and a work robot is synchronously moved to follow the work (for example, an automobile) The present invention can be similarly applied to an outfitting equipment assembly line in a manufacturing plant, a component assembly line or an inspection line in various manufacturing plants, and the like.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing a configuration of the present invention.

FIG. 2 is a perspective view of a coating surface inspection apparatus according to an embodiment of the present invention.

FIG. 3 is a schematic plan view of a coating surface inspection device.

FIG. 4 is a block diagram of a control system of the coating surface inspection device.

FIG. 5 is a part of a flow chart of a routine for paint surface inspection control.

FIG. 6 is a part of a flowchart of a routine for control of coating surface inspection.

FIG. 7 is a part of a flowchart of a routine for control of coating surface inspection.

FIG. 8 is the remaining part of the flowchart of the routine for controlling the coating surface inspection.

FIG. 9 is a flowchart of a subroutine of teaching information correction processing of paint surface inspection control.

FIG. 10 is an explanatory diagram of a plurality of zones and teaching positions shared by the inspection robot.

FIG. 11 is an explanatory diagram of an imaging unit area, a coordinate system, and the like.

[Explanation of symbols]

KS Paint surface inspection station (production line) 1 Car body (work) 5 Carriage (work transfer means) 6 Conveyor (work transfer means) 7 Inspection robot 8 Travel guide path 8a Ball screw shaft (robot movement drive means) 9 Robot movement drive motor (Robot movement drive means) 10 Rotary encoder (robot position detection means) 20 Main controller (synchronous control means, cooperative control means) 27 Conveyor drive motor (work transfer means) 28 Rotary encoder (work position detection means) 30 Robot controller ( Robot control means)

Claims (4)

[Claims] 1. A work transfer means for transferring a work, a robot for performing a predetermined work on the work transferred by the work transfer means, and a robot movement drive means capable of moving the robot along a work transfer path. In a production line control device comprising: a work position detection means for detecting a position in the transfer direction of a work transferred by the work transfer means; and a position of a robot that is driven to move in the work transfer direction by the robot movement drive means. A robot position detecting means for detecting the robot position, a robot control means for controlling the robot, a synchronous control means for controlling the robot movement driving means so that the robot moves synchronously following the work being conveyed, and the work position Using the position of the work detected by the detection means and the position of the robot detected by the robot position detection means , A control by the robot control unit, and a cooperative control means to coordinate and control by the synchronization control unit, the production line control apparatus characterized by comprising a. 2. The robot is a robot that divides a plurality of work zones of a work and performs a work including a playback-type work based on teaching information taught in each zone. 1. The production line control device according to 1. 3. The cooperative control means controls the robot movement driving means via the synchronous control means so that the robot has a positional relationship with respect to the work at the time of starting the work in each work zone. The production line control device according to claim 2, wherein the production line control device is configured. 4. The coordinate control means, when the robot position detected by the robot position detection means reaches a limit position on the downstream side in the work transfer direction, the work position and the limit position detected by the work position detection means. 4. The production line control device according to claim 3, further comprising teaching information correction means for calculating a correction amount for correcting the teaching information based on the above and outputting it to the robot control means.