JP2757228B2 - Image data processing method for image sensor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an image sensor that detects a circular reference portion of a stopped workpiece in order for an automatic machine, for example, a robot to work the workpiece that is sequentially conveyed. The image data is temporarily stored in a memory, the image data read from the memory is processed, a position of a reference portion is detected, and the position data itself or the processed data is used as an image sensor for teaching to a robot. The present invention relates to an image data processing method.

[Conventional technology]

In a production line, when working with a robot while processing the image data of the reference part and checking the position of the workpiece, to increase the tact interval, the processing speed of the image data must be increased accordingly. Must. Therefore,
If the image data of the entire area of the imaging surface is processed each time, the processing speed becomes slower.

[Problems to be solved by the invention]

Therefore, the present invention provides an image data processing method of an image sensor that can increase the processing speed of image data with respect to a reference position of a workpiece when it is assumed that a circular reference portion is to be imaged. The purpose is to:

[Means for solving the problem]

According to the present invention, in order to achieve this object, the processing area for reading and processing the image memory is set to a circular shape larger than the address area of the image memory occupied by the circular reference portion located at the standard position. It is set to a ring shape surrounding a circle, and when performing image data processing, first process the image data read from the circular processing area, and if the image of the reference portion can be detected with a predetermined area or more, The position of the reference portion is detected and the position data is taught to the automatic machine. On the other hand, if the area is smaller than a predetermined area, the data is read out from the ring-shaped processing area to perform image data processing, and the image of the circular processing area is processed. Along with the data processing result, or when a predetermined area is not obtained and the image of the ring-shaped processing area has a predetermined area or more, the position of the reference portion is detected alone.

[Action]

As shown in FIG. 1, if the image V1 of the circular reference portion detected by processing the image data of the circular processing region R1 is determined to have a predetermined area or more and a predetermined accuracy can be guaranteed,
The position of the reference portion is detected from the address of the image V1 and output to the automatic machine.

When the image V1 is smaller than the predetermined area, reading is also performed from the ring-shaped processing region R2, and the position of the reference portion is detected together with the image V2 and the image V1 of the reference portion detected by the image data processing.

When the image V1 of the circular processing region R1 is not detected and the image V2 of the ring processing region has a predetermined area or more, the position of the reference portion is detected by the data alone.

〔Example〕

FIG. 2 shows an arrangement for carrying out an image data processing method according to the present invention, and shows an image data processing apparatus for teaching a stop position of a conveyed vehicle 10 to a robot 11.

Among them, 12 is a TV camera for imaging a circular reference hole 19 on the bottom surface of the body. 13 performs level discrimination of the image signal corresponding to the read scan output from the TV camera 12,
An image signal processing circuit that outputs a binarized dot image signal.

Reference numeral 14 denotes an image data processing device that is a personal computer or a microcomputer. This computer temporarily takes in a dot image signal corresponding to the reading scan into an image memory. For reading, as shown in FIG. 3, a circular processing region R11 centered on the origin O of the imaging surface.
The address range of the ring-shaped processing region R12 is programmed in advance. Also, the amount of deviation from the actual center of gravity point with respect to the detected area value of the reference hole image is stored as a table.

Accordingly, the CPU first takes in the dot image data of the circular processing region R11 from the image memory according to the program, and determines whether or not a part or all of the image of the reference hole 19 exists. If there is, when the area value is calculated and it is determined that the area exceeds the normal area, for example, 1/2, the position of the center of gravity is obtained, and the correction value is searched from the table to obtain the actual reference hole 19. Calculate the center of gravity of the image. If it is determined that the area value is less than 1/2, the image data of the processing region R12 is fetched, and the center of gravity position is similarly obtained from the image data of both. Similarly, when the area is detected outside in the processing region R12 and the area is more than 1/2, the processing is performed alone, and when the area is smaller, the remaining area R13, that is, the entire area is processed as a result. The obtained center position data of the reference hole 19 is processed as it is or processed into position data of the shape of a specific portion of the vehicle 10 and output to the robot 11.

Next, the operation will be described with reference to the flowcharts of FIGS.

When the vehicle 10 is conveyed and stopped and an operation start signal is issued from the line, the TV camera 12 captures an image of the reference hole 19, and the image signal processing circuit 13 can discriminate the reference hole 19. Are detected and output as dot image signals. The image data processing device loads the dot image data into the image memory in response to the read scan. First, dot image data is read from the processing region R11 to detect a reference hole image, that is, a target image V11.
/ 2 or more, the center of gravity position P is obtained and the center O
The correction amount d on the straight line L connecting the door searches the table corresponding to the area, and transmits the final actual position data by calculating the center-of-gravity position P _0. When an image of a perfect circle is obtained in the processing region R11, the actual center of gravity position P ₀ is directly obtained without correction.
Ask for.

If the area of the target image V11 is less than or equal to 、, the dot image data of the processing region R12 is read out, and if the target image V12 is detected, the area together with the data of the target image V11 exceeds 1/2. Or the target image V1 that exceeds the area 1/2 by only the processing region R12
When detecting the 2 similarly detects the correction calculation or by direct actual gravity center position P _0.

When an out-of-bounds target image is detected in the processing region R12, if the area exceeds half, the same correction is performed and the actual center-of-gravity position P is calculated.
₀ look, 1/2 or less when further processing the dot image data of the remaining processing region R13 detects an object image V13, obtains the center-of-gravity position P ₀ Te併. If no more than half of the target image is detected in this area as well, abnormality notification is performed.

In the above-described embodiment, a case where one reference hole is imaged has been described. However, when a plurality of reference holes are imaged by one image sensor, a plurality of types of processing areas are set for each.

〔The invention's effect〕

As described above, according to the present invention, by setting the processing area of the image memory to the standard circular address area occupied by the circular reference portion, it is possible to reduce the time required to detect the carry-in position of the workpiece. Furthermore, by processing image data in a wide area corresponding only to a large deviation, image processing is efficiently performed without impairing detection accuracy.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of an image processing method using an image sensor according to the present invention, FIG. 2 is a diagram illustrating a configuration of an image processing device that performs the method, and FIG. 3 is a diagram illustrating the operation of the image processing device. FIG. 4 is a flowchart for explaining the operation of the apparatus. 11… Robot, 12… TV camera, 19… Reference hole.

Claims (1)

(57) [Claims] An image sensor captures an image of a circular reference portion of a stopped workpiece, and stores image data corresponding to the imaging surface in order to cause an automatic machine to work on the workpiece sequentially conveyed. Once, processing the image data read from this image memory to detect the position of the reference portion,
In the image data processing method of the image sensor for teaching the position data to the automatic machine, the processing area for reading and processing the image memory is set to be smaller than the address area of the image memory occupied by the circular reference portion at the standard position. In the case of performing image data processing, first, the image data read out from the circular processing area is processed, and the image of the reference portion is set to a predetermined size. If the area is larger than the area, the position of the reference portion is detected and the position data is taught to the automatic machine. If the area is smaller than the predetermined area, reading is also performed from the ring-shaped processing area. Image data processing, together with the processing result of the image data of the circular processing area, or the predetermined area is not obtained, and the ring-shaped processing area of the Image quasi portion for detecting a position of the reference portion alone in the case of a predetermined area or more, the image data processing method of an image sensor, characterized in that.