JPS62114890A - Shifting method using robot having visual sense - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention conveys workpieces of various sizes supplied by a workpiece supply device using a conveyance device, and uses a robot system with vision to transport the workpieces to the next process. This relates to a method of transferring with precision.

[Conventional technology]

Currently commercially available robot vision devices have a small field of view, and when recognizing a workpiece with a certain height on a two-dimensional plane, the workpiece can be seen from directly above in the center of the field of view. The position and orientation of the workpiece can be recognized with high accuracy, but the workpiece must be viewed diagonally from above at the edge of the field of view, which reduces the accuracy of the position and orientation of the workpiece. As a result, the gripping position of the robot shifts, and the accuracy of transferring the workpiece deteriorates.

[Problem that the invention seeks to solve]

This problem can be solved by reducing the field of view, but
This becomes a problem when workpieces of various sizes are flowing on the same line, and when workpieces are tall.

An object of the present invention is to provide a method for transferring and arranging a workpiece with high accuracy whether the workpiece is located at the center of the field of view or at the edge.

- [Example] Hereinafter, an example of the present invention will be described based on the drawings.

First, as shown in FIG. 2, a scanning area 10 (hereinafter referred to as a mask) is provided at the center of the field of view 9 when teaching the workpiece 8 to the control device 5 of the robot and visual device. The mask 10 is a rectangle whose four sides are straight lines connecting any two points on the outer periphery of the workpiece 8 and whose length is about 1.5 times the length of the straight line of maximum flame.

Next, in FIG. 1, a workpiece 8 is supplied from the supply device 1 by the conveyance device 2, and when detected by the workpiece detector 3, the conveyance device 2 is stopped. Next, the ITV camera 4 captures the image and processes it.
When only the inside of the mask 10 is image-processed and the geometrical features such as the area and the length of the recognition figure are within the range of precision for the teaching data, that is, when the workpiece 8 is inside the mask 10 as shown in FIG. If it is determined that there is a workpiece 8, it is assumed that the workpiece 8 is in a position with good recognition accuracy, and the robot 6 transfers the workpiece 8 to the alignment table 7, which is the next step, and arranges it.

On the other hand, if the geometric features of the recognition figure obtained by image processing only within the mask 10 are outside the range of precision for the teaching data, that is, as shown in FIG.
does not exist within the mask 10, and when the work 8 exists only partially within the mask 10 as shown in FIG. Image processing is performed to recognize the position and posture of the workpiece.

However, the recognition accuracy in these cases is considered to be poor, and
Without being transferred to the sorting table 7, is it a mouth number? The workpiece 8 is placed in the mask 10 at a fixed position and posture by the cutter 6 as shown in FIG. The position and posture when placing the workpiece 8 in the mask 10 are
The robot 6 is taught in advance the position and posture at which it can recognize the object most accurately.

After placing the workpiece 8 inside the mask 10, the robot 6 moves to the mask 1 rather than outside the field of view 9 in order to shorten the movement time.
Evacuate by limiting it to outside of 0. Then - again, mask 10
By image processing only the inside, the position and orientation of the workpieces are recognized, and the robot 6 transfers them to the alignment table 7 and aligns them.

〔Effect of the invention〕

As described above, according to the present invention, the workpieces can be transferred and aligned with high precision no matter where the workpieces are within the field of view. Further, by providing a mask, it is possible to determine whether or not a workpiece exists in the center of the field of view, and to quickly recognize the position and orientation of the workpiece when it is relocated.

[Brief explanation of drawings]

FIG. 1 shows an embodiment of the transfer method according to the present invention. Figure 2 is a diagram when the work is inside the mask, Figure 3
The figure shows the case where the workpiece does not exist inside the mask, Figure 4 shows the figure when the workpiece partially exists inside the mask, and Figure 5 shows the figure when the workpiece is replaced inside the mask. . 1: Workpiece supply device, 2: Workpiece transfer device, 3: Workpiece detector, 4: ITV camera, 5: Oyfy control device, 6: Robot, 7: Workpiece alignment table, 8: Workpiece, 9
: Field of view, 10: Indicates mask.

Claims (1)

[Claims] When transferring a workpiece by a robot equipped with a visual device that recognizes the workpiece from vertically above on a two-dimensional plane, a scanning area suitable for the size of the workpiece is set at the center of the visual field of the visual device, and the workpiece is If the workpiece exists within the scanning area, the robot moves the workpiece to the target position; if the workpiece does not exist within the scanning area, the robot relocates the workpiece within the scanning area, and the visual device moves the workpiece to the target position. A transfer method using a robot with vision, characterized in that the position and orientation of the workpiece within the scanning area are re-recognized by the robot, and then the workpiece is transferred to the target position by the robot.