JPH0545127A - Method and apparatus for measuring position and shape of strip-shaped member - Google Patents

Abstract

PURPOSE:To detect a position accurately by applying a histogram image processing to image signals obtained by picking up images of the vicinities of centers of the front end and the rear end of a strip-shaped member and the vicinities of the right and left edges thereof by a video camera. CONSTITUTION:Mark line parts of the front end 3 and the rear end of a strip-shaped member 1 are illuminated from above, images of the mark line parts of the front end 3 and the rear end 4 are picked up and inputted, a luminance histogram image processing is applied and the positions in the width direction of mark lines of the front end 3 and the rear end 4 are led out. Besides, center edge parts of the front end 3 and the rear end 4 of the member 1 are illuminated from below, an image of either one of them is picked up from above and a shadow image of the center edge part thus obtained is inputted, while an image of the other is picked up from below and inputted. The luminance histogram image processing is applied to these images and the positions of the center edges in the length direction are led out. The exact length of the member 1 can be calculated from the positions in the length direction of the center edges of the front end 3 and the rear end 4 and the positions of the centers in the width direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt-shaped member in which a marker line is formed at a center position in the width direction or at a position at a constant distance from the center over the entire length in the length direction, and particularly, the front end and the rear end are from the side. The present invention relates to a method and apparatus for measuring the position and shape of a belt-shaped member that is obliquely cut when viewed on a member supply conveyor in a tire forming process.

[0002]

2. Description of the Related Art For example, in a tire manufacturing process, a marker line is formed over the entire length in the longitudinal direction at a center position in the width direction or at a position separated from the center by a certain distance, and the front and rear ends are formed. Although a tread that is a belt-shaped member that is cut diagonally as seen from the side is used, the position of the tread relative to the conveyor and the shape of the tread are conveyed while the tread is being conveyed by the member supply conveyor in the tire forming process. In order to perform proper tire molding, it is necessary to measure and confirm whether or not these are stipulated. For example, if the length of the tread is shorter or longer than the specified value, both ends of the tread will not properly overlap when the tread is wound on the forming drum. Further, even if the front and rear ends of the tread are rounded, proper overlapping cannot be obtained. Further, when an automatic molding machine is used, proper molding cannot be performed if the position of the tread with respect to the conveyor deviates from a predetermined position.

As described above, it is necessary to measure the position and shape of the tread conveyed on the conveyor. However, since both ends of the tread are cut obliquely and the optical contrast is low, the position of the edge is accurately detected. Difficult to do. Therefore, various measuring methods have been proposed. For example, Japanese Examined Patent Publication No. 61-61041 discloses a method of detecting the edge position of a tread by using a reflection type photoelectric switch using infrared rays or far infrared rays as a light source. Further, Japanese Patent Laid-Open No. 1-292203 discloses a method of detecting the edge position of a tread using a reflection type displacement detection device. Furthermore, JP-A-2
Japanese Patent Publication No. 44202-44202 discloses a method of picking up an image of an end portion of a tread with a two-dimensional image pickup device, binarizing the obtained image signal, obtaining a histogram of white or black pixels, and detecting an edge position from the histogram. Has been done.

[0004]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
According to the methods disclosed in Japanese Patent No. 61041 and Japanese Patent Laid-Open No. 1-292203, the edge position is accurately and reliably detected by being greatly influenced by the surface condition of the obliquely cut edge, that is, gloss, roughness, and dirt. Since it is not possible to measure the tread length by detecting the time from the detection of the tip position of the tread conveyed on the conveyor belt to the detection of the rear end position,
If the transport speed fluctuates, it causes a measurement error, and there is a drawback that the length of the tread cannot be measured accurately and reliably.

In the method disclosed in Japanese Patent Laid-Open No. 2-44202, the edge of the tread is detected by binarizing the image signal and then obtaining the histogram of white or black pixels to detect the edge. Since there is no large contrast difference in the part, it is difficult to binarize it neatly, and there is a drawback that the edge position cannot be accurately and reliably detected even if the number of white or black pixels after binarization is processed by a histogram. is there.

Further, the above-mentioned conventional method measures the length of the tread, and cannot detect the position or posture of the tread on the conveyor. As described above, when the tread is automatically wound using the automatic molding machine, it is necessary to develop a technique for detecting the tread position and posture on the conveyor in advance.

Further, according to the conventional method, the edge position of the tread can be detected, but the shape of the edge cannot be detected. The shape of the front end and the rear end of the tread may change after the tread is formed, and for example, the left and right ends may be contracted and rounded. If the edge is deformed in this way, there is a possibility that the overlapping state of the front end and the rear end will become defective when wound around the forming drum, and therefore it is also necessary to develop a technique for measuring the shape of the front end and the rear end. .. It is conceivable to take the entire image of the end portion of the tread and perform image processing to measure the shape of the edge, but the range of the image to be processed becomes large and the resolution becomes low.

The object of the present invention is to eliminate the above-mentioned conventional drawbacks, and to accurately and reliably determine the positions, lengths, widths, and shapes of the front and rear ends of the front and rear ends of a belt-shaped member such as a tread in a short time. An object of the present invention is to provide a method and an apparatus for measuring the position and shape of a belt-shaped member that can be measured with a property.

[0009]

In the method for measuring the position and shape of a belt-shaped member according to the present invention, a marker line is formed at the center position in the width direction or at a position at a constant distance from the center over the entire length in the length direction. When measuring the position and shape of the belt-shaped member on the member supply conveyor in the tire molding process, the marker line portions of the front end and the rear end of the belt-shaped member are illuminated from above, respectively, and images are taken from above to mark the front and rear ends, respectively. A step of obtaining a member center by inputting an image of a line portion and performing a luminance histogram image processing to derive the widthwise positions of the leading and trailing marker lines; and a center edge of the leading and trailing ends of the strip-shaped member. The area is illuminated from below, and either the leading edge or the trailing edge is imaged from above, the shaded image of the center edge portion is input, and brightness histogram image processing is performed to send the image. The position of the edge in the length direction is derived, the other is imaged from below, the image of the center edge part is input, and the brightness histogram image processing is performed to derive the position of the center edge in the length direction. And a step of calculating the length of the belt-shaped member from the position of the rear end center edge in the length direction.

Furthermore, in the method for measuring the position and shape of a strip-shaped member according to the present invention, one of the left and right corner portions of the front end and the rear end of the strip-shaped member is illuminated from below and an image is taken from above to capture the left and right corner portions. Input the image and perform luminance histogram image processing to calculate the widthwise positions of the left and right corners, and perform luminance histogram image processing based on the widthwise positions of the left and right corners to determine the lengthwise direction of the left and right corners. The position is derived, and the other is illuminated from below and imaged from above or from below and imaged from below, and the images of the left and right corners are input. 2) Based on the position of the left and right corners in the width direction,
The position of the left and right corners in the lengthwise direction is derived by performing binarized image processing or luminance histogram image processing, and the widthwise position of the left and right corners of the leading and trailing edges and the position of the left and right corners in the lengthwise direction thus derived. And a step of measuring the shapes of the front and rear end portions from the positions in the length direction of the center edges of the front and rear ends and the center position in the width direction.

Further, in the apparatus for measuring the position and shape of the belt-shaped member according to the present invention, the marker line is formed over the entire length in the longitudinal direction at the center position in the width direction or the position at a constant distance from the center, and the front and rear ends are formed. Is an apparatus for measuring the position and shape of a belt-shaped member that is cut obliquely when viewed from the side on the member supply conveyor in the tire forming process, the belt-shaped member, the end where the marking line is upward and the inclined surface is upward. And a first illuminating device that is disposed above the transporting means and that illuminates the marker line portion at the tip of the belt-shaped member from above, and is disposed above the transporting means. A first video camera that images from above the marker line portion at the tip of the belt-shaped member illuminated by the first illumination means, and a marker line portion at the rear end of the belt-shaped member that is arranged above the transport means. A second illuminating device that illuminates from above, a second video camera that is disposed above the transporting device, and that images the rear end marker line portion illuminated by the second illuminating device from above, and the first video camera. A first image processing circuit for performing widthwise luminance histogram image processing on an image of the marker line portion at the tip of the belt-shaped member captured by a video camera to derive the widthwise position of the marker line at the tip; A second image in which widthwise luminance histogram image processing is performed on the image of the marker line portion at the rear end of the band-shaped member captured by the second video camera to derive the widthwise position of the marker line at the rear end. A processing circuit, a third illuminating device that is arranged below the conveying means and illuminates the center edge portion of the tip of the belt-shaped member from below, and a third illuminating device that is arranged above the conveying means and is illuminated by the third illuminating device. Center edge A third video camera for picking up a shadow image of a minute portion, a fourth illuminating device arranged below the conveying means and illuminating the center edge portion of the rear end of the belt-shaped member from below, and a fourth illuminating device below the conveying means. A fourth video camera that is arranged and images the rear center edge portion illuminated by the fourth illumination device, and the first image processing for the image signal output from the third video camera. A third image processing circuit for performing a luminance histogram image processing in the length direction based on the center position of the tip in the width direction derived by the circuit to derive the position of the center edge of the tip in the length direction; The image signal output from the video camera is subjected to the luminance histogram image processing in the length direction based on the center position of the rear end in the width direction derived by the second image processing circuit to obtain the center edge of the rear end. Long The length of the strip-shaped member is calculated from the fourth image processing circuit for deriving the position in the depth direction, the lengthwise positions of the center edges of the leading and rear ends of the strip-shaped member thus derived, and the center position in the width direction. And a first arithmetic circuit for determining the height.

Further, the measuring device for the position and shape of the belt-shaped member of the present invention is arranged below the conveying means and above the conveying means, and a fifth illuminating device for illuminating the left and right corners of the tip. A fifth video camera which is arranged and which captures shadow images of the left and right corners of the tip illuminated by the fifth illuminating device, and which is arranged below the conveying means and illuminates the left and right corners of the rear end. A sixth illuminating device and a sixth illuminating device.
A sixth video camera that images the left and right corners of the rear end illuminated by the lighting device of FIG. 6 and the image of the left and right corners of the tip output from the fifth video camera. Based on the position of the center edge of the tip derived by the image processing circuit, the luminance histogram image processing in the width direction is performed to derive the widthwise positions of the left and right corners of the tip, and the width of the left and right corners thus derived A fifth image processing circuit for performing luminance histogram image processing in the length direction based on the position in the direction and the position of the center edge of the tip to derive the positions in the length direction of the left and right corners of the tip; With respect to the images of the left and right corners of the rear end output from the video camera, the brightness in the width direction is adjusted based on the position of the center edge of the rear end derived by the fourth image processing circuit. Toggle image processing is performed to derive the widthwise positions of the left and right corners at the rear end, and binarized image processing or histogram is performed based on the widthwise positions of the left and right corners and the center edge positions thus derived. A sixth image processing circuit that performs image processing to derive the positions of the left and right corners in the lengthwise direction, and the positions in the width direction of the marker lines at the leading end and the trailing end of the strip-shaped member, leading end, and A second arithmetic circuit for deriving the shapes of the front and rear end portions of the belt-shaped member from the position of the center edge of the rear end in the length direction and the positions of the left and right corners of the front and rear ends in the width and length directions. It is characterized by including.

[0013]

According to the method and apparatus for measuring the position and shape of the belt-shaped member according to the present invention, the position of the belt-shaped member can be measured by detecting the positions in the width direction at the front and rear ends of the marker line, and the front end can be measured. The length of the strip-shaped member can be measured by detecting the position of the center edge at the rear end and the position of the center edge at the rear end. In detecting these positions, histogram image processing is performed on the image signal obtained by imaging with a video camera. As a result, the detection can be performed accurately and reliably. Furthermore, the width of the belt-shaped member can be measured by detecting the positions of the side edges at the front and rear ends, and the shape of the front and rear ends can be measured by detecting the positions of the center edge and the left and right corners. can do. Further, even when detecting these positions, the brightness histogram image processing is performed, so that these positions can be detected accurately and with high reliability. Further, since the band-shaped member imaged by the video camera is only in the vicinity of the center of the front end and the rear end and in the vicinity of the left and right edges, image processing is simplified and desired measurement can be performed in a short time.

[0014]

EXAMPLE FIG. 1 shows the positions and shapes of treads used in the manufacture of tires using the method for measuring the positions and shapes of strip-shaped members according to the present invention, which are measured when the positions and shapes of treads are measured on a member supply conveyor in a tire molding process. It shows a part. The tread 1 is conveyed on the conveyor 2, and its front end 3 and rear end 4 are obliquely cut. In this example, the tread 1 is conveyed with the front end 3 facing upward and the rear end 4 facing downward. On the surface of the tread 1, a marker line 5 extending over the entire length is formed at a center position or a position apart from the center by a certain distance as viewed in the width direction. The marker line 5 faces upward. Transport. The marking line 5 is drawn in a color different from that of the rubber of the tread 1 or is formed as a convex or concave groove, and has a large contrast with the tread surface optically.

In the present invention, positions P1 and P2 in the width direction of the marking line 5 at the front end 3 and the rear end 4 of the tread 1, center edge positions P3 and P4 of the front end 3 and the rear end 4 seen in the length direction, The positions P5 and P6 of the left and right corners of the tip as viewed in the length direction and the positions P7 and P8 of the left and right corners of the rear end as viewed in the length direction are detected, respectively. It should be noted that these positions are obtained with respect to absolute coordinates in the plane where the conveyor 2 is arranged.

FIG. 2 is a schematic side view showing the arrangement of a video camera and an illuminating device for detecting the positions of the above-mentioned parts of the tread 1. The first lighting device 11 is arranged above the conveyor 2 and illuminates the tip 3 of the tread 1 from above. An image of the tip 3 of the tread 1 illuminated by the first illumination device 11 is captured by the first video camera 12 arranged above the conveyor 2. Further, in order to image the marking line 5 at the rear end 4 of the tread 1, a second lighting device 21 is arranged above the conveyor 2 to illuminate the marking line 5 at the rear end portion. An image of the marker line 5 at the rear end portion illuminated by the second illumination device 21 is captured by the second video camera 22 arranged above the conveyor 2. Further, below the conveyor 2, a third lighting device 13 that illuminates the tip 3 of the tread 1 from below is arranged. This third
The illumination device 13 includes a fluorescent lamp and a white plate that diffuses the light emitted from the fluorescent lamp. The shadow image of the tip 3 of the tread 1 illuminated by the third illumination device 13 is captured by the third and fifth video cameras 14 and 15 arranged above the conveyor 2. In this case, the third video camera 14 captures an image of the central portion of the tip 3, and the fifth video camera 15 captures the entire tip.

Below the conveyor 2, a fourth lighting device 23 for spot-illuminating the center edge portion of the rear end 3 of the tread 4 is arranged. The fourth lighting device 23 has an optical fiber that guides the light emitted from the light source lamp. A fourth video camera 24 for picking up an image of the center edge portion of the rear end 4 of the tread 1 illuminated by the fourth illumination device 23 is arranged below the conveyor 2. Further, below the conveyor 2, a fifth illumination device 25 having the same configuration as the third illumination device 13 is arranged, and a shadow image of the rear end 4 of the tread illuminated by this fifth illumination device is taken. In order to enable the sixth video camera 26 above the conveyor 2,
To place.

In FIG. 2, the third illumination device 13 for illuminating the tip 3 of the tread 1 from below is common to the third and fifth video cameras 14 and 15, but in principle, this illumination is performed. The device can be configured with two lighting devices. In this case, the illumination device for the third video camera 14 that images the center edge portion of the tip 3 can illuminate only the central portion viewed in the width direction, and the illumination for the fifth video camera 15 can be performed. The device may illuminate the corner portion of the tip.

FIG. 3 is a block diagram showing the overall structure of the belt-shaped member position and shape measuring apparatus according to the present invention. First to sixth video cameras 12, 22, 14, 24, 15
The image signals output from the first and sixth image processing circuits 31 to 36 are supplied to the first to sixth image processing circuits 31 to 36, respectively, and subjected to predetermined image processing, respectively, and the front end 3 and the rear end 4 of the tread 1 shown in FIG. The positions P1 to P8 of the parts are obtained. The method of image processing in these image processing circuits 31 to 36 will be described later in detail.

An image signal from the first video camera 12 for picking up an image of the vicinity of the marker line 5 on the tip 3 of the tread 1 is supplied to the first image processing circuit 31 to determine the position P1 of the marker line in the width direction at the tip. An image signal from the second video camera 22 that calculates and images the vicinity of the marker line at the rear end 4 of the tread is supplied to the second image processing circuit 32, and the position P2 in the width direction of the marker line at the rear end is supplied. To calculate. Furthermore, the image signal output from the third video camera 14 is supplied to the third image processing circuit 33, and based on the position P1 of the marker line 5 obtained by the first image processing circuit 31, the tip 3 of the tread 1 is fed. The position P3 of the center edge in the length direction is calculated, and the image signal output from the fourth video camera 24 is converted into the fourth image processing circuit 3.
5 and supplied to the second image processing circuit 32, and the rear end 4
The position P4 in the length direction of the center edge of the rear end 4 of the tread 1 is calculated on the basis of the position P2 of the marker line 5. The positions P1, P2, P3 and P4 calculated in this way are further supplied to the first arithmetic circuit 37 so that the length L of the tread 1 can be reduced.
Ask for. As shown in FIG. 2, the third and fourth video cameras 14 and 24 arranged above the conveyor 2 are separated from each other by a predetermined distance D, and this distance D is input to the first arithmetic circuit 37. The length L of the tread can be calculated from the distance D and the positions P1, P2, P3 and P4. As shown in FIG. 2, the length L of the tread 1 is the distance from the center edge of the front end 3 to the base of the inclined end surface of the rear end 4.

The image signal output from the fifth video camera 15 is supplied to the fifth image processing circuit 35, and the center edge position P3 of the tip 3 derived by the third image processing circuit 33 is supplied.
The left and right corner positions P5 and P6 of the tip 3 based on
Is calculated, the image signal output from the sixth video camera 26 is supplied to the sixth image processing circuit 36, and based on the center edge position P4 of the rear end 4 derived by the fourth image processing circuit 34, Left and right corner positions P7 and P8 of the edge 4 are calculated. Furthermore, the first to sixth image processing circuits 31 to 3
The positions P1 to P8 detected in 6 are supplied to the second arithmetic circuit 38, and the shapes of the front end 3 and the rear end 4 are detected based on these positions. The length L of the tread 1 thus detected, the width and shape of the tread at the leading end 3 and the trailing end 4, the positions P1 and P2 of the marker line 5 at the leading and trailing ends, the leading end center edge position P3, and the trailing end center edge The position P4 is supplied to the determination circuit 39, these values are compared with the reference range, and if the value exceeds the reference range, a tread abnormality signal is generated.

Next, an image processing method in the image processing circuits 31 to 36 will be described. First, the processing in the first and second image processing circuits 31 and 32 will be described. These detect the positions P ₁ and P ₂ in the width direction of the marker line 5 at the front end 3 and the rear end 4 of the tread 1, but since the image processing is the same at the front end and the rear end, only the front end is detected. explain. The field of view of the first video camera 12 is set so as to capture an image of a portion near the tip 3 of the tread 1 as indicated by F in FIG. After capturing all the image signals in the field of view F, a window W is set in the field of view and a luminance histogram in the width direction is obtained for the image signals in this window. The brightness histogram thus obtained is shown in FIG. The vertical axis of the brightness histogram in the width direction shows a value obtained by integrating the brightness values of pixels on the line extending in the length direction of the tread 1, and the horizontal axis shows the position of each line in the width direction.

When the luminance histogram in the width direction is obtained in this manner, a peak is shown at the position of the marker line 5, so the position P ₁ ′ of this peak line on the image is obtained.
On the other hand, since the coordinate P ₀₁ ′ on the image of the origin P ₀₁ of the absolute coordinate in the plane of the conveyor 2 is obtained in advance, the position P _{1 in} the width direction of the marker line 5 at the tip 3 is P ₁ = k ₁ ( P ₁ ′ −P ₀₁ ′)
Can be obtained from In this formula, k ₁ represents a scale factor. The center position of the tip 3 of the tread 1 viewed in the width direction can be obtained by adding or subtracting a constant distance between the marker line 5 and the center position to P ₁ obtained as described above. The center position P _{2 in} the width direction of the rear end 4 of the tread 1 can be similarly obtained.

Next, the operation of processing the image signal representing the shadow image of the tip 3 of the tread 1 imaged by the third video camera 14 by the third image processing circuit 33 to detect the position P _{3 of the} center edge. explain. Field of view F of the third video camera 14
Is set so as to capture an image of a portion near the tip 3 as shown in FIG. Next, the window W is set in the visual field F based on the position P1 of the marker line 5 in the width direction obtained as described above. The setting method of the window W is to set the window W in the field of view F based on the position P2 of the marker line 5 in the width direction. Next, when the luminance histogram in the length direction is obtained, it suddenly changes at the center edge as shown in FIG. The coordinate P ₃ ′ on the image in the length direction of this point is obtained. Since the coordinate P ₀₃ ′ on the image of the origin P ₀₃ of the absolute coordinate in the plane of the conveyor 2 is obtained in advance, the position P ₃ of the center edge at the tip ₃ is P ₃ = k ₃ (P
It can be obtained from the ₃ '-P _03'). In this equation, k ₃ represents a scale factor.

The center edge position P _{4 at} the rear end 4 of the tread 1 is calculated by processing the image signal output from the fourth video camera 24 by the fourth image processing circuit 34. is similar to the case of detecting the position P ₃ of the center edge at the tip 3 described above, the fourth back surface image of the illuminated rear 4 in the illumination device 23 of which is arranged below the conveyor 2 in this case Since the fourth video camera 24 takes an image, the luminance becomes large on the bottom of the tread,
It becomes a little smaller on the inclined surface. Therefore, the luminance histogram in the length direction suddenly changes at the center edge as shown in FIGS. 8a and 8b. The coordinate P ₄ ′ in the length direction of this point is obtained. Since the origin P ₀₄ ′ of the absolute coordinate in the plane of the conveyor 2 is obtained in advance, the rear end 4
The position P ₄ of the center edge at is P ₄ = k ₄ (P ₄ ′ −P
It can be obtained from ₀₄ ′). In this formula, k ₄ represents a scale factor.

Next, a method of obtaining the positions P ₅ and P ₆ of the left and right corners of the tip 3 of the tread 1 in the fifth image processing circuit 35 will be described. First, the vicinity of the tip 3 of the tread 1 is imaged by the fifth video camera 15, and its visual field F is assumed to include left and right corners as shown in FIG. Next, the first windows WR1 and WL1 are set on the left and right side edges based on the measurement result of the center edge position P ₃ obtained by the third image processing circuit 33. These windows are set at positions as shown in FIG. 9 based on the leading edge position P ₃ so that the leading edge does not hang inside thereof. Next, when the luminance histogram in the width direction is obtained within these windows, the histogram changes abruptly at each side edge. The coordinates of this point on the image in the width direction P _5x ′ and
_Find P _6x ′. Origin of absolute coordinates in the plane of conveyor 2
'Since, calculated in advance, the position P _5x and P _6x in the width direction of the corner of the left and right tip _{5, P 5x = k 5x (P} 5x' coordinates P _05x on the image of the P _05x -P _05x ') P it can be obtained from _{6x = k 6x (P 6x '} -P 05x'). In these equations, k _5x and k _6x represent scale factors. The width of the tip portion of the tread 1 can be measured from the positions P _5x and P _{6x of} the left and right corners thus detected.

Second windows WR2 and WL2 as shown in FIG. 9 based on the widthwise positions of the left and right corners and the center edge position P ₃ detected as described above.
Are set respectively. And these windows WR2
When the luminance histogram in the length direction is obtained in each of WL2 and WL2, the histogram changes abruptly at the left and right edges. The coordinates P _5y ′ and P _6y ′ on the image in the length direction of this point are obtained. Since the coordinate P _05y ′ on the image of the origin P _05y of the absolute coordinate in the plane of the conveyor 2 is obtained in advance, the positions P _5y and P _6y of the left and right corners of the tip 5 in the lengthwise direction are P _5y = k _5y (P _5y ′ −P _05y ′) P _6y ＝ k _6y (P _6y ′ −P _05y ′) In these equations, k _5y and k _6y indicate scale factors.

Next, a method for obtaining the positions P ₇ and P ₈ of the left and right edges of the rear end 4 of the tread 1 will be described. Figure 2
As shown in, the fifth illumination device 25 is arranged below the conveyor 2 and the sixth television camera 26 is arranged above the conveyor to capture a shadow image of the rear end of the tread. The field of view F of the sixth video camera 26 is large so as to simultaneously include the left and right corner portions as shown in FIG. Similar to the case of detecting the left and right corner positions P ₅ and P ₆ at the tip 3, the left and right side edges are included based on the rear end center edge position P ₄ output from the fourth image processing circuit 34. Left and right first windows WR1 and W
Set L1. The luminance histogram in the width direction is obtained in these windows, and the coordinates P _7x ′ and P _7x ′ on the image in the width direction of the points that change abruptly are obtained. Coordinate P _07x ′ on the image of origin P _07x of absolute coordinates in the plane of conveyor 2
Since the positions P _7x and P _8x of the left and right corners of the rear end 7 are obtained in advance, P _7x = k _7x (P _7x ′ −P _07x ′) P _8x ＝ k _8x (P _8x ′ − It can be obtained from P _07x ′). In these equations, k _7x and k _8x represent scale factors. The width of the rear end portion of the tread 1 can be measured from the positions P _7x and P _{8x of} the left and right corners thus detected.

Next, the left and right corners are included as shown in FIG. 10 based on the widthwise coordinates P _7x and P _{8x of} the left and right corners obtained as described above and the position P ₄ of the rear center edge. The second windows WR2 and W
Set L2 respectively. Next, after binarizing the image signals in these windows, the features of the corner points are extracted to obtain the coordinates of the left and right corner points in the longitudinal direction.
_Find P _7y ′ and P _7y ′. Since the coordinates P _07y ′ on the image of the origin P _07y of the absolute coordinates in the plane of the conveyor 2 are obtained in advance, the positions P _7x and P _8x of the left and right corners of the rear end 7 in the width direction are P _7y = k _7y (P _7y ′ −P _07y ′) P _8y ＝ k _8y (P _8y ′ −P _07y ′) In these equations, k _7y and k _8y indicate scale factors.

The positions P ₁ and P _{2 in} the width direction of the marker line 5 at the front end 3 and the rear end 4 of the tread 1 obtained by the first and second image processing circuits 31 and 32 as described above, and Center edge position P ₃ and rear center edge position P ₄
And the positions P ₅ and P ₆ in the width direction and the length direction of the left and right corners of the tip obtained by the fifth image processing circuit 35, and
The positions P ₇ and P ₈ in the width direction and the length direction of the left and right corners of the rear end obtained by the image processing circuit 36 are supplied to the second arithmetic circuit 38, and the shapes of the edges of the front end and the rear end are obtained. .. The shapes of these edges are not precise, but they are sufficient for judging the quality of the tread.

The present invention is not limited to the above-mentioned embodiments, but various changes and modifications can be added. For example, in the above-described embodiment, the fifth lighting device 25 is arranged below the conveyor 2 in order to detect the positions P7 and P8 of the left and right corners of the rear end 4 of the tread 1,
Although the sixth video camera 26 is arranged above the conveyor to capture the shadow image of the rear end of the tread, the sixth video camera 26 is arranged below the conveyor 2 so that the image of the rear end of the tread is rear surface. You may make it image-capture from. The image processing in this case includes the positions P of the left and right corners of the tip 3.
Similarly to detecting 5 and P6, the luminance histogram image processing in the length direction may be performed to detect the position of the corner in the length direction. Further, the fifth illumination device 25 may be arranged above the conveyor 2 so that the image of the rear end is captured from the back surface. In this case as well, since it is not a shadow image, luminance histogram image processing can be performed.

[0032]

As described above, according to the method and apparatus for measuring the position and shape of the belt-shaped member according to the present invention, the positions of the marking lines at the front and rear ends of the belt-shaped member, the length of the belt-shaped member,
It is possible to simultaneously measure the positions of the center edge of the leading and trailing edges, the positions of the left and right corners of the leading and trailing edges, and the shapes of the leading and trailing edges at the same time at a high speed. Accurate and reliable measurement is possible without being affected by unevenness, gloss, stains, etc. on the front and rear ends.

[Brief description of drawings]

FIG. 1 is a diagram showing a portion whose position is to be detected by a method for measuring the position and shape of a belt-shaped member according to the present invention.

FIG. 2 is a schematic side view showing an arrangement of an illuminating device and a video camera in an embodiment of the position and shape measuring device for a strip-shaped member according to the present invention.

FIG. 3 is a block diagram showing a configuration of an image processing portion of the same.

FIG. 4 is a diagram showing an operation of detecting the position of a marker line at the tip.

FIG. 5 is a graph showing a luminance histogram at that time as well.

FIG. 6 is a diagram showing an operation of detecting the position of the center edge of the tip.

FIG. 7 is a graph showing a luminance histogram at that time as well.

FIG. 8 is a graph showing a luminance histogram when detecting a rear center edge position.

FIG. 9 is a diagram showing an operation for detecting the positions of the left and right corners of the tip.

FIG. 10 is a diagram showing an operation of detecting left and right corner positions of a rear end.

[Explanation of symbols]

 1 tread 2 conveyor 3 tip 4 trailing end 5 marking line P1 tip marking line position P2 trailing marker line position P3 tip center edge position P4 trailing center edge position P5, P6 tip left and right corner position P7 , P8 Left and right corner positions of rear end 11 First lighting device 12 First video camera 13 Third lighting device 14 Third video camera 15 Fifth video camera 21 Second lighting device 22 Second video camera 23 Fourth lighting device 24th 4 video camera 25 5th illuminating device 26 6th video camera 31-36 1st-6th image processing circuit 37, 38 1st and 2nd arithmetic circuit 39 Judgment circuit

Claims (6)

[Claims] 1. The position and shape of a belt-shaped member in which a marker line is formed at the center position in the width direction or at a position at a constant distance from the center over the entire length in the length direction is measured on a member supply conveyor in a tire forming process. In doing so, the front and rear marker line portions of the strip-shaped member are illuminated from above, respectively, images are taken from above and the images of the front and rear marker line portions are input, and brightness histogram image processing is applied to the front and rear markers. Obtaining the member center by deriving the width direction position of the marker line at the rear end; Image from the center edge portion is input, luminance histogram image processing is performed to derive the position of the center edge in the longitudinal direction, and the other is imaged from below and the section is taken. The image of the center edge is input, brightness histogram image processing is performed to derive the position of the center edge in the length direction, and a strip shape is formed from the position of the center edge at the front and rear ends in the length direction and the center position in the width direction. And a step of calculating the length of the member, the method for measuring the position and shape of the belt-shaped member. 2. The left and right corners of one of the front end and the rear end of the belt-shaped member are illuminated from below, the images of the left and right corners are captured from above, the brightness histogram image processing is performed, and the left and right corners are processed. The widthwise positions of the left and right corners are derived, brightness histogram image processing is performed based on the positions of the left and right corners in the widthwise direction, and the positions of the left and right corners in the lengthwise direction are derived, and the other is illuminated from below and imaged from above. Then, the images of the left and right corners are input, brightness histogram image processing is performed to calculate the widthwise positions of the left and right corners, and binarized image processing is performed based on the widthwise positions of the left and right corners. The positions of the left and right corners in the lengthwise direction are derived, and the widthwise positions of the left and right corners of the leading end and the rear end and the positions of the left and right corners in the lengthwise direction thus derived, 2. The belt-shaped member according to claim 1, further comprising the step of measuring the shapes of the front and rear end portions from the positions in the lengthwise direction of the center edges of the front and rear ends and the center position in the width direction. Position and shape measurement method. 3. The left and right corners of one of the front end and the rear end of the strip-shaped member are illuminated from below, the images of the left and right corners are input from above, and brightness histogram image processing is performed to obtain left and right corners. The positions of the corners in the width direction are derived, luminance histogram image processing is performed based on the positions of the left and right corners in the width direction, and the positions of the left and right corners in the length direction are derived. Input the images of the left and right corners, perform luminance histogram image processing to derive the widthwise positions of the left and right corners, and perform the luminance histogram image processing based on the widthwise positions of the left and right corners. The lengthwise positions of the left and right corners are derived, and the widthwise positions of the left and right corners of the leading and trailing edges and the positions of the left and right corners in the lengthwise direction are derived. 2. The belt-shaped member according to claim 1, further comprising the step of measuring the shapes of the front and rear end portions from the positions in the lengthwise direction of the center edges of the front and rear ends and the center position in the width direction. Position and shape measurement method. 4. A band-like shape in which a marker line is formed at a center position in the width direction or at a position at a constant distance from the center over the entire length in the length direction, and a front end and a rear end thereof are obliquely cut when viewed from a side surface. In the device for measuring the position and shape of the member on the member supply conveyor in the tire forming process, a means for transporting the belt-shaped member such that the end where the marking line is upward and the inclined surface is upward is the tip. A first illuminating device which is arranged above the conveying means and which illuminates the marker line portion at the tip of the belt-shaped member from above; and a belt-shaped member which is arranged above the conveying means and which is illuminated by the first illuminating means. A first video camera for picking up an image of the marker line portion at the tip from above; a second illuminating device which is arranged above the conveying means and illuminates the marker line portion at the rear end of the belt-shaped member from above; Above Is arranged, a second imaging the labeled line portion from the upper side of the rear end which is illuminated by the second illuminating means
Of the video camera and the image of the marker line portion at the tip of the strip-shaped member captured by the first video camera is subjected to the luminance histogram image processing in the width direction to derive the position of the marker line at the tip in the width direction. A first image processing circuit, and a width direction luminance histogram image processing is performed on the image of the marker line portion at the rear end of the band-shaped member captured by the second video camera to perform width direction of the marker line at the rear end. A second image processing circuit for deriving the position of ???, a third illuminating device arranged below the conveying means and illuminating the center edge portion of the front end of the belt-shaped member from below, and arranged above the conveying means. , A third image capturing a shadow image of the center edge portion of the tip illuminated by the third illumination device
And a fourth illuminating device which is arranged below the carrying means and illuminates the center edge portion of the rear end of the belt-like member from below, and a fourth illuminating device which is arranged below the carrying means. A fourth video camera for imaging the illuminated center edge portion of the rear end, and a width direction of the front end derived by the first image processing circuit with respect to the image signal output from the third video camera. A third image processing circuit for performing a luminance histogram image processing in the length direction based on the center position to derive the position of the center edge of the tip in the length direction, and an image signal output from the fourth video camera. On the other hand, the luminance histogram image processing in the length direction is performed based on the center position in the width direction of the rear end derived by the second image processing circuit to derive the position in the length direction of the center edge at the rear end. A first operation for obtaining the length of the strip-shaped member from the fourth image processing circuit, the positions in the lengthwise direction of the center edges of the leading and rear ends of the strip-shaped member thus derived, and the center position in the width direction. A device for measuring the position and shape of a belt-shaped member, comprising: a circuit. 5. A fifth illuminating device which is arranged below the conveying means and which illuminates the left and right corners of the tip, and a tip which is arranged above the conveying means and which is illuminated by the fifth illuminating device. A fifth video camera that captures shadow images of left and right corners, a sixth illuminating device that is arranged below the conveying means and illuminates the left and right corners of the rear end, and is arranged above the conveying means. And a sixth video camera that captures shadow images of the left and right corner portions of the rear end illuminated by the sixth illuminating device, and an image of the left and right corner portions of the tip output from the fifth video camera. On the other hand, the luminance histogram image processing in the width direction is performed based on the position of the center edge of the tip derived in the third image processing circuit to derive the widthwise positions of the left and right corners of the tip. Based on the positions of the left and right corners in the width direction and the position of the center edge of the tip, which are derived in this way, the luminance histogram image processing in the length direction is performed to derive the positions of the left and right corners of the tip in the length direction. The image processing circuit and the width direction based on the position of the center edge of the rear end derived by the fourth image processing circuit with respect to the images of the left and right corners of the rear end output from the sixth video camera. The brightness histogram image processing is performed to derive the widthwise positions of the left and right corners at the rear end, and the binarized image processing is performed based on the widthwise positions of the left and right corners and the center edge positions thus derived. And a sixth image processing circuit for deriving the positions of the left and right corners in the lengthwise direction, and the positions in the width direction and the tips of the marker lines at the front and rear ends of the strip-shaped member derived as described above. Second arithmetic circuit for deriving the shapes of the front and rear end portions of the belt-shaped member from the positions of the center edge of the rear end and the rear end in the length direction and the positions of the left and right corners of the front and rear ends in the width and length directions. 5. The position and shape measuring device for a strip-shaped member according to claim 4, further comprising: 6. A fifth illuminating device which is arranged below the carrying means and illuminates the left and right corners of the tip, and a fifth illuminating device which is arranged above the carrying means and is illuminated by the fifth illuminating device. A fifth video camera that captures shadow images of the left and right corners, a sixth illuminating device that is arranged below the conveying means and illuminates the left and right corners of the rear end, and is arranged below the conveying means. And a sixth video camera for taking images of the left and right corner portions of the rear end illuminated by the sixth illuminating device, and an image of the left and right corner portions of the tip output from the fifth video camera. Then, the luminance histogram image processing in the width direction is performed based on the position of the center edge of the tip derived by the third image processing circuit to derive the widthwise positions of the left and right corners of the tip. Fifth image processing for deriving the luminance histogram image processing in the length direction based on the derived positions in the width direction of the left and right corners and the position of the center edge of the tip to derive the positions in the length direction of the left and right corners of the tip. And the luminance in the width direction based on the position of the center edge of the rear end derived by the fourth image processing circuit for the images of the left and right corners of the rear end output from the sixth video camera. Histogram image processing is performed to derive the widthwise positions of the left and right corners at the rear edge, and the luminance histogram image in the lengthwise direction is obtained based on the widthwise positions of the left and right corners and the center edge positions thus derived. A sixth image processing circuit that performs processing to derive the positions of the left and right corners in the length direction, and the width of the marker lines at the front and rear ends of the strip-shaped member derived as described above. The position of the center edge of the front and rear ends in the length direction, and the positions of the left and right corners of the front and rear ends in the width and length directions. The device for measuring the position and shape of a belt-shaped member according to claim 4, further comprising two arithmetic circuits.