Variation measuring device and variation measuring method

Abstract

The present invention provides a variation measuring device 10 and a variation measuring method that can easily measure the variation in the stopping position of a moving object M1. [Solution] The variation measuring device 10 includes, for example, an imaging means 11 that photographs the state in which the moving body M1 has stopped moving at a predetermined position, a deviation amount acquisition means 12 that compares the image captured by the imaging means 11 with a normal image captured by the imaging means 11 after the moving body has been stopped in advance at the target stopping position and acquires the amount of deviation of the stopping position of the moving body M1 from the target stopping position, and a graphical representation means 13 that displays the amount of deviation obtained by the deviation amount acquisition means 12 on a two-dimensional chart.

Description

Technical Field

[0001] The present invention relates to a variation measuring device and a variation measuring method for measuring the variation in the stop position of a moving body that stops moving at a predetermined position.

Background Art

[0002] In the manufacturing processes of various products, for example, parts may be supplied to a predetermined position by a shooter. When using a shooter, at the time of installation, adjustment is made so that the variation in the stop position of the parts supplied by the shooter is within a predetermined range. Conventionally, for example, parts are circulated through the installed shooter a plurality of times, and an operator manually measures how much the stop position of the parts deviates from the target stop position to confirm the variation in the stop position of the parts. However, conventionally, since it was measured manually, it lacked reliability, and there was a problem that it was difficult and time-consuming to manually measure the two-dimensional positional deviation in the X direction, Y direction, and rotational direction of the stop position.

[0003] Further, Patent Document 1 describes a method for inspecting the pass / fail of a manufactured product. As an inspection method, the three-dimensional CAD data of the first inspection jig reflecting the upper limit intersection of the product and the three-dimensional CAD data of the second inspection jig reflecting the lower limit intersection of the product are compared with the three-dimensional measurement image data of the product, and the pass / fail of the product is determined based on the comparison result. According to this method, without measuring the dimensions of the manufactured product, based on how much the dimensions of the manufactured product deviate from the design drawing, the pass / fail of the product can be automatically inspected efficiently and with high accuracy in a short time. However, in this method, there was a problem that comparison could not be performed without the three-dimensional CAD data of the equipment and the inspection jig.

[0004] Note that the above-described problem was not only in the case of measuring the variation of the parts supplied by the shooter, but also in the same way in the case of measuring the variation in the stop position of a moving body that stops moving at a predetermined position, such as an automatic transfer device.

Prior Art Documents

[0005] [Patent Document 1] Japanese Patent Publication No. 2003-240537 [Overview of the project] [Problems that the invention aims to solve]

[0006] This invention was made based on these problems, and aims to provide a variation measuring device and variation measuring method that can easily measure the variation in the stopping position of a moving object. [Means for solving the problem]

[0007] The variation measuring device of the present invention measures the variation in the stopping position of a moving body that stops moving at a predetermined position, and comprises an imaging means for photographing the state in which the moving body has stopped moving at the predetermined position, and a deviation amount acquisition means for comparing the image captured by the imaging means with a normal image captured by the imaging means after the moving body has been stopped in advance at the target stopping position, and acquiring the amount of deviation of the stopping position of the moving body from the target stopping position.

[0008] The variation measurement method of the present invention measures the variation in the stopping position of a moving body that stops moving at a predetermined position, and includes a shooting procedure for taking a picture of the moving body when it has stopped moving at the predetermined position, and a deviation amount acquisition procedure for comparing the image taken in the shooting procedure with a normal image taken in advance when the moving body has been stopped at the target stopping position, and obtaining the amount of deviation of the moving body's stopping position from the target stopping position. [Effects of the Invention]

[0009] According to the present invention, by comparing the captured image with a standard image, the amount of deviation from the target stopping position of the moving object is obtained. Therefore, CAD data of the equipment is not required, and variations in the stopping position can be measured easily and with high accuracy. Thus, the accuracy of the equipment can be measured simply, and machine errors and malfunctions of the equipment can be easily detected.

[0010] Furthermore, by displaying the obtained deviation amount on a two-dimensional chart, the variation in the stopping position can be easily recognized visually. Moreover, by displaying the acceptable range of deviation amount within a circle on the two-dimensional chart, it is easy to determine whether the degree of variation is acceptable or not. [Brief explanation of the drawing]

[0011] [Figure 1] This figure shows a schematic configuration of a variation measuring device according to one embodiment of the present invention. [Figure 2] Figure 1 is a block diagram showing the configuration of the variation measurement device. [Figure 3] Figure 1 is an illustrative diagram of an image captured using the imaging device shown. [Figure 4] This figure shows an example of a two-dimensional chart created using the diagramming method shown in Figure 1. [Figure 5] This figure shows an example of a report displayed using the display means shown in Figure 1. [Figure 6] This diagram shows the flow of a variation measurement method according to one embodiment of the present invention. [Modes for carrying out the invention]

[0012] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0013] Figures 1 and 2 show the configuration of a variation measuring device 10 according to one embodiment of the present invention. The variation measuring device 10 measures the variation in the stopping position of a moving body M1 that stops moving at a predetermined position. Examples of the moving body M1 include supplies such as parts supplied to a predetermined position by a chute M2, and automated transport devices such as trolleys that transport transported items from a transport source to a transport destination. In this embodiment, the case in which the variation in stopping position is measured when multiple parts are supplied to a predetermined position as a moving body M1 by a chute M2 will be explained as an example.

[0014] The variation measuring device 10 includes, for example, an imaging means 11 that photographs the state in which the moving body M1 has stopped moving at a predetermined position, and a deviation amount acquisition means 12 that compares the image captured by the imaging means 11 with a normal image captured by the imaging means 11 after the moving body M1 has been stopped in advance at the target stopping position, and acquires the amount of deviation of the stopping position of the moving body M1 from the target stopping position.

[0015] The imaging means 11 includes, for example, a camera 11A such as a CCD camera, and is positioned to photograph the moving body M1 from above at a predetermined position where the moving body M1 stops moving. The imaging means 11 is configured to photograph, for example, multiple moving bodies M1 individually. The imaging range of the imaging means 11 is preferably set to be wide enough so that the entire moving body M1 is captured even if the stopping position of the moving body M1 varies at the predetermined position. Figure 3 shows an image diagram of a photograph taken by the imaging means 11. In Figure 3, the moving body M1 is shown in gray for clarity.

[0016] The imaging means 11 also preferably has a position adjustment assistance function 11B for assisting in the position adjustment of the camera 11A when installing the camera 11A, for example, so that a specific position of the moving body M1 stopped at the target stop position becomes the center position of the captured image. The position adjustment assistance function 11B can be constituted by, for example, a computer, and is configured to function as a deviation amount acquisition means 12 by executing a program, and is connected to the camera 11A. The position adjustment assistance function 11B is preferably configured to display, for example, the center position of the angle of view on the real-time video of the imaging means 11 and display a message for assisting in aligning the specific position of the moving body M1 shown in the real-time video with the center position of the angle of view. Examples of the specific position of the moving body M1 include the center of the moving body M1 and a characteristic shape portion of the moving body M1. Thereby, the operator can adjust the position of the camera 11A while viewing the real-time video of the imaging means 11, so that the specific position of the moving body M1 stopped at the target stop position and the center position of the captured image can be aligned.

[0017] The imaging means 11 may use, for example, either a black-and-white camera or a color camera, but it is preferable that the captured image and the regular image be grayscale images. This is because a black-and-white camera has high accuracy, and it is preferable to use the grayscale image output by the black-and-white camera as a standard.

[0018] In addition, when the imaging means 11 captures an image of the moving body M1, it is preferably configured to display coordinate axes on the real-time video, for example, as shown in FIG. 3, so that the operator can know the coordinate directions (X direction and Y direction) of the displayed moving body M1. In FIG. 3, the coordinate directions are indicated by broken lines.

[0019] The deviation amount acquisition means 12 can be configured by, for example, a computer, and is configured to function as the deviation amount acquisition means 12 by executing a program. The deviation amount acquisition means 12 is, for example, connected to the imaging means 11, and is preferably configured to detect a matching image that matches the normal image from each captured image by pattern matching, and obtain the coordinates (x, y) of each matching image and the rotation angle (θ) of each matching image with respect to the normal image.

[0020] The normal image may be an image of the entire moving body M1, or may be an image of a part of the moving body M1, for example, an image obtained by extracting some characteristic parts. The coordinates (x, y) of the matching image obtained by the deviation amount acquisition means 12 are, for example, the coordinates of a specific position of the moving body M1. The coordinates (x, y) of the matching image can be easily obtained, for example, by setting the specific position of the moving body M1 stopped at the target stop position as the center position (0, 0) of the captured image.

[0021] The deviation amount acquisition means 12 is preferably configured to detect a matching image that matches the normal image from the captured image by pattern matching using, for example, image processing technology. The deviation amount acquisition means 12 preferably has, for example, a detection means 12A that detects a matching image that matches the normal image from the captured image using the normal image, and a coordinate / rotation angle calculation means 12B that obtains the coordinates (x, y) of the matching image detected by the detection means 12A and the rotation angle (θ) of the matching image with respect to the normal image. Note that AI (Artificial Intelligence) may be used for pattern matching. For example, each captured image may be input to a learning model that has learned the normal image, and a matching image that matches the normal image may be detected.

[0022] Preferably, the variation measuring device 10 also includes, for example, a graphic representation means 13 that displays the amount of deviation obtained by the deviation amount acquisition means 12 on a two-dimensional chart, a maximum deviation amount extraction means 14 that extracts the maximum deviation amount from the deviation amounts of a plurality of moving bodies M1 obtained by the deviation amount acquisition means 12, and a display means 15 such as a display that shows the two-dimensional chart created by the graphic representation means 13 and the maximum deviation amount extracted by the maximum deviation amount extraction means 14. The graphic representation means 13 and the maximum deviation amount extraction means 14 can be configured by, for example, a computer, and are configured to function as the graphic representation means 13 or the maximum deviation amount extraction means 14 by executing a program.

[0023] Preferably, the graphic representation means 13 is configured to plot the coordinates (x,y) of the matching image obtained by the displacement amount acquisition means 12 on a two-dimensional chart. This is because the variation in the stopping position of the moving body M1 can be easily recognized visually. The rotation angle (θ) of the matching image relative to the normal image may be displayed on the two-dimensional chart with marks and numerical values, or it may be shown numerically in a table or other separate document. Figure 4 shows an example of a two-dimensional chart created by the graphic representation means 13. In Figure 4, the coordinate positions of the matching image are indicated by black circles.

[0024] Furthermore, it is preferable that the graphic representation means 13 be configured to display, for example, the allowable range of deviation in the stopping position of the moving body M1 by enclosing it in a circle on a two-dimensional chart. This is because the operator can easily determine whether or not the variation in the stopping position is within an acceptable range by looking at the two-dimensional chart. It is preferable that the allowable range of deviation be configured to be set arbitrarily, for example. The allowable range of deviation may be shown in stages. Figure 4 shows the case where a first allowable range with high accuracy and a second allowable range with lower accuracy are displayed. In Figure 4, the first allowable range is shown by a dotted line, and the second allowable range is shown by a dashed line.

[0025] When displaying the two-dimensional chart created by the graphic generation means 13 and the maximum deviation amount extracted by the maximum deviation amount extraction means 14 on the display means 15, it is preferable to display them as a report combining the two-dimensional chart, the maximum deviation amount, and the captured image, for example, as shown in Figure 5.

[0026] Furthermore, it is preferable that the variation measuring device 10 be mounted on a transport cart, for example, so that it can be carried around and used for measurement.

[0027] This variation measuring device 10 is used, for example, as follows to measure the variation in the stopping position of a moving body M1 that stops moving at a predetermined position. Figure 6 shows the flow of the variation measuring method using the variation measuring device 10.

[0028] First, as a preparation procedure, for example, a regular image is prepared by stopping the mobile body M1 at the target stopping position and capturing it with the imaging means 11 (preparation procedure; step S110). When setting up the camera 11A of the imaging means 11, it is preferable to use, for example, the position adjustment assist function 11B to adjust it so that the specific position of the mobile body M1 stopped at the target stopping position becomes the center position of the captured image. The regular image is preferably a grayscale image.

[0029] After the preparation procedure (step S110), for example, the shooter M2 supplies multiple moving bodies M1 to predetermined positions, and the shooting means 11 individually photographs each moving body M1 as it stops moving at the predetermined position (shooting means; step S120).

[0030] Next, for example, the displacement amount acquisition means 12 compares each captured image obtained in the shooting procedure (step S120) with a pre-prepared normal image and acquires the displacement amount from the target stopping position for each moving body M1 (displacement amount acquisition procedure; step S130). Specifically, for example, it is preferable to detect matching images that match the normal image from each captured image using pattern matching with image processing technology, and to determine the coordinates (x,y) of each matching image and the rotation angle (θ) of each matching image relative to the normal image. AI may be used for pattern matching; for example, each captured image may be input into a learning model that has been trained on the normal image, and matching images that match the normal image may be detected.

[0031] Next, for example, the graphic representation means 13 displays the amount of displacement obtained in the displacement amount acquisition procedure (step S130) on a two-dimensional chart (graphic representation procedure; step S140). Specifically, for example, the coordinates (x,y) of the matching image are plotted on the two-dimensional chart. The rotation angle (θ) of the matching image relative to the normal image may be displayed on the two-dimensional chart with marks and numerical values, or it may be shown numerically in a table or other separate document. Preferably, on the two-dimensional chart, for example, the allowable range of the displacement amount of the stopping position of the moving body M1 is enclosed in a circle.

[0032] Furthermore, the maximum displacement extraction means 14 extracts the maximum displacement from the displacement amounts of the multiple moving bodies M1 obtained in the displacement acquisition procedure (step S130) (maximum displacement extraction procedure; step S150). Next, the two-dimensional chart created in the graphicization procedure (step S140) and the maximum displacement extracted in the maximum displacement extraction procedure (step S150) are displayed on the display means 15 (display procedure; step S160). In this case, it is preferable that the display means 15 displays a report combining, for example, the two-dimensional chart, the maximum displacement, and the captured image.

[0033] As described above, according to this embodiment, by comparing the captured image with the standard image, the amount of deviation of the moving body M1 from the target stopping position is obtained. Therefore, CAD data of the equipment is not required, and variations in the stopping position can be measured easily and with high accuracy. Thus, the accuracy of the equipment can be measured simply, and machine errors and malfunctions of the equipment can be easily detected.

[0034] Furthermore, by displaying the obtained deviation amount on a two-dimensional chart, the variation in the stopping position can be easily recognized visually. Moreover, by displaying the acceptable range of deviation amount within a circle on the two-dimensional chart, it is easy to determine whether the degree of variation is acceptable or not.

[0035] The present invention has been described above with reference to embodiments, but the present invention is not limited to the above embodiments and can be modified in various ways. For example, although each component was described in detail in the above embodiments, the specific structure and shape of each component may differ, and the present invention does not have to include all of the above-mentioned components, but may include other components as well. [Explanation of symbols]

[0036] 10...Variation measuring device, 11...Shooting means, 11A...Camera, 11B...Position adjustment assist function, 12...Deviation amount acquisition means, 12A...Detection means, 12B...Coordinate / rotation angle calculation means, 13...Graphization means, 14...Maximum deviation amount extraction means, 15...Display means, M1...Moving body, M2...Shooter

Claims

1. A variation measuring device for measuring the variation in the stopping position of a moving object that stops moving at a predetermined position, A photographing means for photographing the state in which the moving object has stopped moving at a predetermined position, A shift amount acquisition means compares the captured image taken by the aforementioned shooting means with a regular image taken by the aforementioned shooting means after the moving body has been stopped in advance at the target stopping position, and acquires the amount of deviation of the moving body's stopping position from the target stopping position. A variation measuring device characterized by being equipped with [a specific feature].

2. The variation measuring device according to claim 1, further comprising a graphical representation means for displaying the amount of deviation obtained by the deviation amount acquisition means on a two-dimensional chart.

3. The aforementioned graphical representation means displays the stopping position of the moving object on a two-dimensional chart, and also displays the allowable range of the deviation amount enclosed in a circle. The variation measuring device according to claim 2, characterized in that it is a variation measuring device.

4. A variation measurement method for measuring the variation in stopping position of a moving object that stops moving at a predetermined position, A shooting procedure for photographing the state in which the moving object has stopped moving at a predetermined position, A shift amount acquisition procedure is performed to compare the captured image taken by the above shooting procedure with a regular image taken after stopping the moving object at the target stopping position in advance, and to obtain the amount of deviation of the stopping position of the moving object from the target stopping position. A method for measuring variation, characterized by including [a specific element].

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