JPH0758173B2 - Part shape recognition method and part quality judgment method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention provides a CC for silhouettes of parts supplied at predetermined positions.
The present invention relates to a part shape recognition method and a part quality determination method configured to be recognized by a D camera and to detect the shape of the silhouette as a distance in the Y direction on the XY coordinates from a reference position.

[Prior Art] and [Problems to be Solved by the Invention] Recently, various good / bad determination devices for a component have been developed, which use a CCD camera to recognize the shape of the component and strictly detect the defect of the component. ing. In this type of quality determination device, when recognizing a part, the silhouette of the part is created on the image of the CCD camera, and the silhouette is detected as binarized data by the pixels forming the image of the CCD camera. Whether or not the part is non-defective is determined by detecting the length of the outer circumference of the silhouette and the area of the silhouette by the change of the binarized data of the pixel in the previous period and comparing these with those of the reference part. . Therefore, when recognizing the shape of a part, it is necessary to detect the outer circumference and the area of the silhouette, which not only takes a long time, but also when the part flows in contact with an adjacent part, Since the outer circumference and area of the silhouette cannot be detected, the quality of the parts cannot be determined, and the component supply speed must be adjusted so that the parts do not come into contact with adjacent objects. There are drawbacks such as not being suitable.

The present invention is intended to eliminate the above-mentioned drawbacks, and detects the shape of the silhouette of the component recognized by the CCD camera as the distance in the Y direction on the XY coordinates, and recognizes the shape of the component in a short time. An object of the present invention is to provide a method for recognizing the shape of a component and a method for determining the quality of a component, which are capable of accurately determining the quality of a component that is continuously supplied at high speed in a short time.

[Means for Solving the Problems]

In order to solve the above problems, a CCD camera and a light source for irradiating light rays are arranged at positions sandwiching a desired part having a circular portion, and a circular silhouette of the part is provided for each pixel forming an image of the CCD camera. While converting to binarized data and storing the binarized data at the address in the image memory corresponding to the pixel, it also stores the reference position on the XY coordinates, and from this reference position, the silhouette in the Y direction on the XY coordinates. In the part shape recognition method that recognizes the shape of the part by detecting the distance to the edge of the part, the center of the silhouette of the part is calculated from the center of the silhouette while the part supply direction is the X direction on the XY coordinate. Each position on a straight line extending parallel to the X direction at a position separated by the radius of the silhouette of the reference part is sequentially called as a reference position, and the distance in the Y direction from each of these reference positions to the silhouette contour is called as a reference position. It is configured to recognize a jet contour.

Whenever the distance in the Y direction from each reference position to the silhouette contour is detected as the silhouette contour, the distance in the Y direction to the corresponding silhouette edge on the silhouette of the reference component is called and compared. It may be configured to determine that the component is defective when the distances in the Y direction from the respective reference positions are continuously determined to be defective.

[Action]

According to this method, when the desired component is located in front of the CCD camera, the silhouette of the component is converted into binarized data for each pixel forming the image of the CCD camera by receiving the light beam emitted from the light source. The binarized data is stored at an address in the image memory. When detecting the shape of the component from these binarized data, the center of the circular silhouette is calculated with the supply direction of the component as the X direction on the XY coordinates. Further, each position on a straight line extending in the X direction is sequentially called as a reference position at a position away from the center by the radius of the silhouette of the reference component, and the distance in the Y direction from each reference position to the silhouette edge is calculated. And stored as the silhouette outline. Therefore, even if a part comes into contact with an adjacent part and passes in front of the CCD camera, most of the outer periphery of the silhouette of each part can be detected except for the contact part, and no matter what condition the part passes through. It is possible to surely recognize a predetermined shape and determine whether the shape is good or bad.

When determining the quality of a component, the distance in the Y direction on the XY coordinates from the reference position to the edge of the silhouette is sequentially detected from the X coordinate of the reference position in the X direction, while the reference component is detected. It is only necessary to call the distance in the Y direction on the silhouette in the X direction from the position of the X coordinate of the reference position in order, and it is possible to determine whether the shape of the component is good or bad without considering the deviation of the passing position of the component. In this case, if the difference is not within the predetermined error, it is immediately determined that the component is defective, and the defect is displayed. Further, it is possible to determine that the defect detection of the component is performed only when the defect detection is continuously performed, and it becomes possible to determine the quality of the component without erroneous determination by eliminating the influence of cutting chips, dust and the like.

〔Example〕

Embodiments will be described below with reference to the drawings. In FIG. 1, reference numeral 1 denotes a pass / fail determination device for determining the pass / fail of the shape of the desired component 2. The transfer belt 4 and the transfer belt are made of a transparent material, which is guided by the mounting plate 3 and continuously supplies the components horizontally. 4, which is an example of a light source that emits light rays upward from below 4 through the gap of the mounting plate 3, and above the conveyor belt 4 is arranged so that the light receiving surface is below and the light rays from the strobe 5 are received. It consists of a CCD camera 6. The image of the CCD camera 6 is composed of a large number of pixels arranged vertically and horizontally, and when each pixel receives a light beam from the strobe 5, it is configured to output an analog image signal.

Further, 7 is a control device of the quality determination device 1 for the component 2,
It has a control unit 8 which is a microprocessor. The control unit 8 includes the reference radius of the reference component 2 via the interface bus 9 and the distance in the Y direction on the XY coordinates from each reference position on a straight line described below with respect to the reference component 2 to the edge. A storage unit 10 that stores various information including a reference value 1x, a component detection unit 11 that detects whether or not there is a component 2 at a predetermined position and outputs a component detection signal, and a strobe drive command signal Strobe drive unit to irradiate
12, a CCD camera interface 13 and a frame RAM 14 forming an image memory are connected.

The CCD camera interface 13 is an A / D converter 13 for A / D converting an analog image signal corresponding to a pixel on the image.
a, a timing pulse generation unit 13b for instructing A / D conversion timing, a signal binarization unit 13c for binarizing the digital image signal output from the A / D conversion unit 13a, and a timing pulse in order every time the pulse is generated. An address generator 13d that generates an address is provided, and the binarized data of the signal binarizer 13c is a frame RAM every time a timing pulse is generated.
It is configured to be output to and stored in the address within 14. The frame RAM 14 has an address corresponding to each pixel, stores the binarized data of each pixel at the corresponding address, and the coordinate data on the XY coordinates corresponding to each address is also stored. The addresses corresponding to the coordinate data on the XY coordinates are mutually obtained.

The controller 8 waits for a component detection signal from the component detector 11 as shown in FIGS.

2) The strobe drive command signal is output and the drive command signal is output to the CCD camera interface 13 to drive the timing pulse generation unit 13b, and the timing pulse is A / D conversion unit 13a, signal binarization unit 13c and address generation. The data is output to the section 13d, the silhouette of the component 2 is converted into binarized data of each pixel forming the screen of the CCD camera 6, and this is stored in an address in the frame RAM 14 corresponding to each pixel. (Silhouette is stored as "1" and other than silhouette is stored as "0") 3) Let the direction in which parts are supplied be the X direction on the XY coordinates,
The edges of the target silhouette in two orthogonal directions are detected, and the coordinate data on the XY coordinates of the center C0 of the silhouette is calculated from the addresses in the frame RAM 14 corresponding to the pixels serving as the edges.

4) Add the reference radius stored in advance to the Y coordinate data of the calculated center C0, and calculate the silhouette center C0.
The coordinate data of the first reference position Y0 on the straight line extending in the X direction at a position away from the reference radius by is calculated and stored.

5) Set the reference position (X0, Y0) to the coordinate data for calling the binarized data.

6) When the binarized data of the address in the frame RAM 14 corresponding to the coordinate data is called and this is "1", 1
Jump to 7).

The above (1) to 6) are referred to as step I. ) 7) Subtract (−1) from the coordinate data in the Y direction.

8) It is judged whether the coordinate data in the Y direction is equal to the coordinate data in the Y direction of the silhouette center C0, and when both are the same, 20)
Jump to.

9) Call the binarized data of the address corresponding to the coordinate data, determine whether this is "1" or "0", and if not "1", return to 7).

10) The coordinate data is stored as the coordinates of the edge of the silhouette, and the distance a in the Y direction from the reference position to the edge is calculated.

11) Y corresponding to the coordinate data of the reference part in the X direction
Call the reference value 1x consisting of the distance in the direction and this and the distance a
And are compared, and when the difference is within a predetermined error e, jump to 15).

12) It is determined whether the difference between the distance a and the reference value 1x is smaller than a predetermined value M (M is a value sufficiently larger than the error e), and if it is not small, the process jumps to 20).

13) The defect detection counter is incremented, it is determined whether the count value is N, and when it is not N (N is an integer greater than 2), the process jumps to 16).

14) The component defect display command signal is output, and at the same time, the component rejection command signal is output and the process returns to 1).

15) Reset the defect detection counter.

16) Add (+1) to the coordinate data in the X direction, call the next reference position on the straight line extending in the X direction, call the binarized data of the address corresponding to the coordinate data, and return to 6).

The above (7) to 16) is referred to as Step II. ) 17) Add (+1) to the coordinate data in the Y direction.

18) Call the binarized data corresponding to the coordinate data, determine whether the value is "1" or "0", and when it is "1", return to 17).

19) The coordinate data is stored as the coordinates of the edge of the silhouette, the distance a in the Y direction from the reference position to the edge is calculated, and the process returns to 11).

The above (17) to 19) are referred to as Step III. ) 20) Repeat steps I, II and III. (However, in step II 8), “Jump to 20)” is jumped to “21).”, 12) “Jump to 20)” is jumped to “21).”, 16) In the above description, "(+1) is added to the coordinate data in the X direction" is read as "(-1) is subtracted from the coordinate data in the X direction." ) (20 above) is referred to as Step IV. 21) With the coordinate data of the reference position on the − side in the Y direction as −Y0, the above steps I, II, III and IV are repeated. (However, in step II, step 7) "From the coordinate data in the Y direction (-
1) Subtract. From the coordinate data in the Y direction (+1)
to add. , 17) in the coordinate data in the Y direction (+
1) Add. From the Y coordinate data (-1)
Subtract. In step 7) of step IV, "(-1) is subtracted from the coordinate data in the Y direction." Is added to the coordinate data in the Y direction (+1). "Return to 1).", Jump to 20) in 12). Return to "1.", 17) "Add (+1) to the coordinate data in the Y direction." Read as "(-1) is subtracted from the coordinate data in the Y direction." ) Is configured as follows.

In the component quality determination device 1, when the component 2 reaches a predetermined position below the CCD camera 6, the component detection unit 11 outputs a component detection signal and the control unit 8 outputs a strobe drive command signal. Therefore, the strobe drive unit 12 operates,
Light is emitted from the strobe 5 toward the CCD camera 6, and the circular silhouette of the component 2 is recognized as an analog image signal of a pixel forming an image of the CCD camera 6. At the same time, a drive command signal is output from the controller 8 to the CCD camera interface 13, and a timing pulse is emitted from the timing pulse generator 13b. The analog image signal is sequentially converted into a digital image signal through the A / D conversion unit 13a for each timing pulse, and this is converted into a signal binarization unit.
At 13c, the silhouette is converted into binary data with the "1" signal and the other signals with the "0" signal. at the same time,
The address corresponding to the pixel is calculated by the address generator 13d, and the binarized data is sequentially output to the address of the frame RAM 14 and stored.

When all the binarized data possessed by the pixels forming the image of the CCD camera 6 are stored in the frame RAM 14, the direction in which the parts are immediately supplied is set to the X direction on the XY coordinates as shown in FIG. Is calculated, and the coordinate data of the center C0 of the silhouette is calculated.

Further, from the coordinate data of the center C0 of the silhouette and the reference radius stored in the storage unit 10 in advance, the coordinates of the first reference position Y0 on a straight line passing through the center C0 and extending in the X direction at a position away from the center C0 by the reference radius. Data is calculated and stored in the storage unit 10.

The reference position (X0, Y0) is set in the coordinate data for calling the binarized data, and the binarized data of the address in the frame RAM 14 corresponding to this coordinate data is called. A value other than the silhouette is determined by "0". When the binarized data is "0" and there is no silhouette on the reference position, (-1) is subtracted from the coordinate data of the reference position in the Y direction, and the address of the frame RAM 14 corresponding to this coordinate data is calculated. The binarized data is called and the above determination is repeated. When the binarized data is changed to "1" and the edge of the silhouette is detected, the edge of the reference position and the edge of the silhouette are calculated from the coordinate data in the Y direction and the coordinate data in the Y direction of the reference position at this time. The distance a in the Y-direction between and is calculated. This distance a is calculated for each coordinate data at the position in the X direction from the reference radius and compared with the reference value 1x stored in the storage unit 10, and it is determined whether the difference is within a predetermined error e. The quality of the component 2 is determined.
When it is determined that the shape of the component 2 is good as a result of the determination, the coordinate data in the X direction of the coordinate data is called and (+1) is added to this, and the next reference position on the straight line extending in the X direction is called. Is called. The binarized data of the address in the frame RAM 14 corresponding to the coordinate data of the reference position is called, the pass / fail judgment is performed as in the previous time, and this is repeated.
Therefore, even if a part comes into contact with an adjacent part and passes in front of the CCD camera, most of the outer periphery of the silhouette of each part can be detected except for the contact part, and no matter what condition the part passes through. It is possible to surely recognize a predetermined shape and determine whether the shape is good or bad.

If the shape of the component 2 is determined to be defective as a result of the determination,
In order to eliminate the influence of chips, dust, and the like attached to the component 2, the defect detection counter is incremented every time a defect of the component 2 is detected, and the defect detection is stored. This defect detection occurs N times in succession. Only when it is determined that the component 2 is defective, the defect display command signal of the component 2 is output, and the rejection command signal of the component 2 is output to prepare for the next inspection.

On the other hand, the frame RAM14 corresponding to the coordinate data of the reference position
If the binarized data of the address is "1" and the silhouette of the part 2 is on the reference position, (+1) is added to the coordinate data of the reference position in the Y direction to correspond to the coordinate data. The determination of the binary data of the address in the frame RAM 14 is similarly performed. If the determination is repeated and the coordinate data in the Y direction becomes zero while subtracting (−1),
The reference position is called, and the same as the + direction of the X coordinate-
Whether the circumferential shape of the silhouette in the direction is good or bad is determined. Next, the reference position (X0, -Y0) in the-direction on the Y coordinate is called, and the quality of the edge of the silhouette in the + direction on the Y coordinate is determined in the same manner. After the completion of the determination of the shape of the entire circumference of the silhouette, it is possible to prepare for the next determination of quality.

〔The invention's effect〕

As described above, according to the present invention, the silhouette of a part having a circular portion is captured by the CCD camera, and the moving direction of the part is determined by the X direction.
The center of the silhouette of the part is calculated as the X direction on the Y coordinate, and each position on the straight line extending in the X direction at a position separated from the center of the silhouette of the part by the radius of the silhouette of the reference part is sequentially called as the reference position. , The distance in the Y direction from each reference position to the silhouette edge is sequentially calculated and these are recognized as the outline of the silhouette, so that the parts come into contact with adjacent parts and pass in front of the CCD camera. However, most of the outer periphery of the silhouette of each component can be detected except for its contact portion, and the quality of the predetermined shape can be reliably determined regardless of the condition under which the component passes.
Further, according to the present invention, when comparing with the silhouette of the reference part, it is only necessary to measure the distance from the reference straight line to the silhouette edge, so that the distance between the edges in the Y direction is measured. Not only can the time be halved, but erroneous determination of the quality of the component due to the adherence of cutting chips, dust, etc. to the component can be eliminated. Furthermore, the present invention eliminates the erroneous determination of the quality of the component due to the adherence of cutting chips, dust, etc. to the component because the defect is detected only when the defect detection of the edge of the silhouette of the component occurs continuously. Therefore, there is an advantage that the quality can be accurately determined.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view of a component quality determination device according to the present invention, FIGS. 2a, 2b and 2c are flowcharts showing the operation of the component quality determination device according to the present invention, and FIG. 3 is related to the present invention. It is explanatory drawing which shows operation | movement of the principal part of the quality determination apparatus of components. 1 ... Pass / fail judgment device, 2 ... Parts, 3 ... Mounting plate, 4 ... Conveyor belt, 5 ... Strobe, 6 ... CCD camera, 7 ... Control device, 8 ... Control unit, 9 ... Interface bus, 10 ... storage section, 11 ... component detection section, 12 ... strobe drive section, 13 ... CCD camera interface, 13a ... A / D conversion section, 13b ... timing pulse generation section, 13c ... Signal binarization unit, 13d ... Address generation unit, 14 ... Frame RAM,

Claims (2)

[Claims] 1. A CCD camera and a light source for irradiating light rays are arranged at positions sandwiching a desired component having a circular portion, and a circular silhouette of the component is binarized for each pixel constituting an image of the CCD camera. The data is converted and the binarized data is stored at the address in the image memory corresponding to the pixel, while the reference position on the XY coordinates is stored, and the edge of the silhouette in the Y direction on the XY coordinates is stored from this reference position. In the method of recognizing the shape of a part by detecting the distance to the part, the center of the silhouette of the part is calculated while the center of the silhouette of the part is calculated by setting the method of supplying the part as the X direction on the XY coordinates. Each position on a straight line extending in the X direction at a position separated by the radius of the silhouette of the component is called as a reference position in sequence, and the distance in the Y direction from each reference position to the silhouette contour is defined as the silhouette contour. Shape recognition method of the component, characterized in that to recognize. 2. A CCD camera and a light source for irradiating light rays are arranged at positions sandwiching a desired component having a circular portion, and a circular silhouette of the component is binarized for each pixel constituting an image of the CCD camera. The data is converted and the binarized data is stored at the address in the image memory corresponding to the pixel, while the component supply direction is set to the X direction on the XY coordinates, and the center of the silhouette of the component is calculated. Each position on a straight line extending in the X direction is called as a reference position at a position away from the center of the object by the radius of the silhouette of the reference part, and the distance in the Y direction from each of these reference positions to the silhouette outline is defined as the silhouette outline. Each time it is detected as, the distance in the Y direction to the corresponding silhouette edge on the silhouette of the reference part is called to compare and determine these, and the distance in the Y direction from each reference position. When it is determined continuously as defective, quality decision method of parts and determining that defective parts.