JPH0735968B2 - Three-dimensional shape measuring device for long materials - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional shape measuring apparatus for a long material for measuring the shape of an object to be measured which is obtained by bending a long material.

[0002]

2. Description of the Related Art Conventionally, for measuring whether or not an object to be measured, which is formed by bending an elongated material, for example, an object to be measured, which is bent into a three-dimensional shape, is bent as originally designed. As a measuring device, there is known one having a contactor, as disclosed in JP-A-62-36514. In such a measuring device, a three-dimensional movable
The contactor is supported by the three-dimensional movement mechanism, and the amount of movement of the three-dimensional movement mechanism when the contactor is brought into contact with the outer circumference of the object to be measured is detected. Then, there is known one that measures the shape of the object to be measured from the coordinates of a plurality of contact points.

[0003]

However, in such a conventional measuring device, a three-dimensional moving mechanism must be provided in order to move the contactor three-dimensionally, and there is a problem that the structure is complicated. It was Further, there is a problem that the operator has to bring the contactor and move it so as to contact the outer circumference of the object to be measured, which is a troublesome operation.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a three-dimensional shape measuring apparatus for a long material, which has a simple structure and is easy to operate, with the object of solving the above problems.

[0005]

In order to achieve such an object, the present invention has the following constitution as means for solving the problem. That is, as illustrated in FIG. 1, the entire measured object M1 obtained by bending a long material placed on a plane is 2
Whole detector M2 for detecting as a three-dimensional image and the whole detector
Of the object to be measured M1 based on the two-dimensional image from the device M2.
Central point detecting means M3 for detecting the central point of the straight line portion is provided.
Well, it is possible to scan on the plane and to measure the object M1.
Some measurement points are enlarged from the image of the whole detector M2
First and second image detectors for detecting as two-dimensional image
M4 and M5 are arranged at a predetermined position with a predetermined distance therebetween, and the center detected by the center point detecting means M3.
Based on the points, the first and second image detectors M4 and M5 are
The object to be measured M1 is controlled by scanning the plane.
Image control means M6 for detecting the linear portion of
Projection calculating means M7 for calculating the projection center lines of the measurement object M1 onto the plane from the images of the measurement object M1 by the second image detectors M4 and M5, and the calculated both projection center lines and The first and second image detectors M4 and M5
3 for a long material, which is provided with a centerline calculating means M8 for calculating respective planes including these from the position and calculating the intersection line of both planes as the centerline of the object to be measured M1. That is the configuration of the dimension measuring device.

[0006]

In the three-dimensional shape measuring apparatus for a long material having the above-mentioned structure, the whole detector M2 is placed on a flat surface.
The whole of the measured object M1 in which the material is bent is examined as a two-dimensional image.
The center point detecting means M3 outputs 2 from the whole detector M2.
The center point of the straight line part of the object to be measured M1 is detected based on the three-dimensional image.
Put out. The image control means M6 is the center point detection means.
Based on the center point detected by M3, the first and second images
Control the image detectors M4 and M5 to scan on the plane
Then, the first and second image detectors M4 and M5 are connected to the object to be measured M1.
The two-dimensional image of the straight line part of is detected. Projection calculation means M7
Calculates the projection centerlines from the 2D image onto the plane.
The center line calculation means M8 outputs the projection center line and the first and
From the positions of the two image detectors M4 and M5, a plane including them is calculated, and an intersection line between the two planes is calculated as a center line of the object to be measured M1.

[0007]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 2 is a schematic configuration diagram of a three-dimensional shape measuring apparatus for a long material which is an embodiment of the present invention. Reference numeral 1 denotes a mounting table, which is formed of rectangular translucent frosted glass in this embodiment, and has a flat plane 2 on the upper side. In this embodiment, the short side direction of the plane 2 is the X axis, and the long side direction is the Y axis. Scales 4 and 6 are drawn on the plane 2 at regular intervals along each axis. There is. The Z axis is perpendicular to the plane 2 and the XYZ coordinates are defined with the plane 2 as a reference.

The scales 4 and 6 may be drawn on the plane 2 in a grid pattern for each unit length, or
A mark or the like may be drawn at the intersection. A fluorescent lamp 8 is provided below the mounting table 1, and the mounting table 1
The object to be measured 10 mounted on the mounting table 1 is illuminated through the light. Here, the object to be measured 10 is a three-dimensionally bent long material such as a round bar or a pipe.

Further, above the mounting table 1, the whole detector 1
2 is provided, the whole detector 12 includes a two-dimensional image pickup device 13a, and the lens 13b forms an entire image of the mounting table 1 on the two-dimensional image pickup device 13a.
An image in a range of 50 mm (X axis) × 1250 mm (Y axis) is formed. This two-dimensional image sensor 13
In the present embodiment, a is such that the image is decomposed into 512 × 512 pixels, quantized by each element, photoelectrically converted into a charge amount corresponding to the light amount for each element, and then output as image data. Has been done.

In this embodiment, the whole detector 12 is provided right above the center of the plane 2. Then, it has been measured in advance that the center of the two-dimensional image pickup device 13a is at a predetermined position (x0, y0, z0) of coordinates having the X-axis, Y-axis, and Z-axis as coordinate axes. Further, first and second image detectors 14 and 16 are provided on both sides of the whole detector 12 at a predetermined distance in the Y-axis direction and at a predetermined height from the plane 2. The first and second image detectors 14 and 16 are
Since they have the same configuration, one first image detector 14 will be described in detail with reference to FIG.

The first image detector 14 includes first and second scanners 18 and 20, and the first scanner 18 is a plane 2
As shown in FIG. 4, a pulse motor 23 rotates a mirror 22 which is placed on the object 10 and reflects the object 10 to be measured, around an axis parallel to the X axis. Then, the second scanner 20 causes the mirror 24 that reflects the image projected on the mirror 22 to move to the Z position.
The pulse motor 25 rotates about an axis parallel to the axis.

The first image detector 14 is also provided with a two-dimensional image pickup device 26, which has a two-dimensional image pickup device 28, and the image projected on the mirror 24 is the lens 3.
0, it is arranged so as to be formed on the two-dimensional image pickup device 28. In the present embodiment, the two-dimensional image pickup device 28 decomposes an image into 512 × 512 pixels, is quantized by each device, and is photoelectrically converted into a charge amount corresponding to the light amount of each device, and then image data is obtained. Is output as.

The size of the image formed on the two-dimensional image pickup device 28 is an image of a part of the object to be measured placed on the plane 2 at a measurement position, and the measurement accuracy and the number of pixels 512 × 512
Is determined in relation to. In this embodiment, 15 is set on the plane 2.
The range of 0 mm × 150 mm can be output as enlarged image data. Further, it has been measured in advance that the center of the two-dimensional image pickup device 28 is at a predetermined position (x1, y1, z1) of coordinates having the X-axis, Y-axis, and Z-axis as coordinate axes.

This predetermined position (x1, y1, z1) is 2
It is not the actual coordinate position of the three-dimensional image pickup device 28 but the mirror 2
Since it is reflected at 2, 24, it is a position on optical coordinates. In the present embodiment, the mirror 2 is located on an extension connecting the object to be measured 10 and the mirror 22 on the plane 2 and from the position of the mirror 22.
It is at a position equal to the distance connecting the two, the mirror 24, and the two-dimensional image pickup device 28.

On the other hand, like the first image detector 14, the second image detector 16 also includes the first and second scanners 32 and 34 and the two-dimensional image pickup device 35. As shown in FIG. 4, the first scanner 32 rotates the mirror 36 by the pulse motor 37, and the second scanner 34 also rotates the mirror 3.
8 is rotated by the pulse motor 39 so that the plane 2 can be scanned. Then, the two-dimensional imager 35
Is equipped with a two-dimensional image sensor (not shown), and the center coordinates of the two-dimensional image sensor have been measured in advance to be at predetermined positions (x2, y2, z2) of the X-axis, Y-axis, and Z-axis coordinates. There is.

The overall detector 12, the first and second image detectors 14 and 16 are connected to a control circuit 40, and the control circuit 40 stores a well-known CPU 42 and control programs and data in advance. ROM44, readable and writable RA
It is configured as a logical operation circuit centering on M46, and input / output circuits 48 are connected to each other via a common bus 50 to perform input / output with the outside.

Then, the CPU 42, via the input / output circuit 48, the whole detector 12, the first and second image detectors 14,
Image data is input from 16 and these signals, R
The CPU 42 is configured to display the measurement result on the display 52 via the input / output circuit 48 based on the programs and data in the OM 44 and the RAM 46.

Next, the operation of the three-dimensional shape measuring apparatus for a long material according to this embodiment will be described with reference to the flowchart of FIG. First, when the power is turned on, the planes 2 are scanned by the first and second image detectors 14 and 16, and a correction process is executed (step 100). In the present embodiment, the first and second image detectors 14 and 16 optically scan the plane 2 and output the image data. Therefore, the angle of projection on the plane 2, that is, the XY plane. DUT 10 output as image data depending on the position in
Of different length.

Therefore, the pulse motors 22, 23, 37,
39 is rotated and the scales 4 and 6 drawn on the plane 2 are scanned, and the image data at each position of the coordinates of the XY axes corresponding to the pulse is read. And the scale 4, 1 of 6
With the number of pixels at intervals as the unit length, correction data of the unit length at each position on the plane 2 is obtained.

The object to be measured 1 placed on the plane 2
The whole 0 is detected by the whole detector 12 and the whole image data is read (step 110). This whole image data is binarized by a predetermined threshold value, and the center point of the straight line portion of the DUT 10 is detected from the contour and the end point of the DUT 10 is detected (step 120).

Taking the case shown in FIG. 2 as an example, the image data from the overall detector 12 corresponds to the projected image of the object 10 to be measured on the plane 2, and the first to third parts of the straight line portion of this projected image. XY coordinates (xa, ya) of each point of the central points a, b, c, (x
b, yb) and (xc, yc) are calculated. In addition, both ends of the image of the DUT 10 are defined as temporary end points d and e, and X
The Y coordinates (xd, yd) and (xe, ye) are calculated.

Subsequently, the first and second image detectors 14 and 16
The pulse signals are output to the pulse motors 23, 25, 37, 39 so that the center of the image of the image of the image is aligned with the first center point a (xa, ya), and the first scanners 18, 32, the second scanner 20, Rotate each 34 (step 130).
Then, it is determined whether or not there is the DUT 10 in this image (step 140).

For example, as shown in FIG.
When the first center point A of the three-dimensional coordinate of is at a position of a predetermined height from the plane 2, if the image center is aligned with the first center point a on the plane 2, Images may not be obtained. In this case, the first scanner 18, 3
2. By rotating the second scanner 20, 34,
The object to be measured 10 is scanned so that it is in the center of the image (step 150).

The central point A of the three-dimensional coordinates is the whole detector 12
Is on a straight line connecting the coordinates (x0, y0, z0) of the center of X and the center point a (xa, ya) on the plane 2 which is the projected image. Therefore, at the time of scanning, the scanning time is shortened by tracing along this straight line.

Then, as shown in FIG. 6, scanning is performed so that the object 10 to be measured comes to approximately the center of the image by the first image detector 14. Further, as shown in FIG. 7, the object 10 to be measured is scanned so that the object 10 is located substantially at the center of the image by the second image detector 16. When it comes to the center of the image, the scanning is stopped and the enlarged image data from the first and second image detectors 14 and 16 is read (step 160).

Next, the magnified image data corresponds to the projected image of the object 10 to be measured on the plane 2, and the magnified image data is binarized by a predetermined threshold value. From the contours, the respective projection center lines g and h on the plane 2 are calculated in the XY coordinate system as in the following formula (step 170).

Y = Ag X + Bg Y = Ah X + Bh Then, the formulas showing these projection center lines g and h, and the first,
Positional coordinates (x1, y1, z of the second image detectors 14, 16)
1) and (x2, y2, z2), X of the object to be measured 10 is calculated.
The first center line La in the YZ coordinate system is calculated (step 180). The calculation of the first center line La is first performed with reference to FIG.
As shown in, the projection center lines g and h and the position coordinates (x1, y1, z1) of the first and second image detectors 14 and 16, (x1
2, y2, z2) and m, n in the XYZ coordinate system including
The plane is calculated by the following formula.

Am X + Bm Y + Cm Z + Dm = 0 An X + Bn Y + Cn Z + Dn = 0 Next, since the intersecting line of the m and n planes is the first center line La of the DUT 10, the formulas of the above m and n planes are given. From the above, the first center line La is calculated as two linear equations as in the following equation.

Y = ALaX + BLa Z = CLaX + DLa Then, it is determined whether or not the steps 130 to 180 have been executed for all the first to third center points a, b and c calculated by the step 120. (Step 190).

The above-described processing is executed for all the first to third center points a, b and c to obtain the first to third center lines La and Lb.
, Lc, the coordinates of the end points D and E are detected (step 200). To detect the end points D and E, first, the end points d and e detected by the processing in step 120 are scanned so that they are at the centers of the images of the first and second image detectors 14 and 16.

Then, the image data is binarized by a predetermined threshold value, and from the contour of the outer periphery of the end of the object to be measured 10,
Calculate the equation for that curve in the XY coordinate system. Figure 9
As shown in, when the end surface of the DUT 10 is circular, this contour curve is an ellipse. The surface including the ellipse is erected so that the ellipse becomes a circle, and the erected angle is calculated. From this angle, the equation of the plane orthogonal to the first center line La is calculated, and the intersections of this plane and the first center line La are calculated as the end points D and E.

In this way, the calculated center lines La, Lb,
The intersection points i and j of Lc and the end points E and D are three-dimensionally displayed on the display 52 as shown in FIG.
It is displayed in YZ coordinates (step 210). in this way,
In the above-described three-dimensional shape measuring apparatus for a long material according to the present embodiment, the whole detector 12 detects the whole image of the object to be measured 10, and based on the whole image data, the straight line portion of the object to be measured 10 is detected. The center points a, b, c and the temporary end points d, e are detected (step 120). Then, the first and second image detectors 1
4, 16 detect the enlarged image of the straight line portion of the DUT 10 based on the center points a, b, c. Next, the projection center lines g and h of the XY coordinate system on the plane 2 are calculated from the enlarged image data, and the position coordinates (x1, y1, z1) of the first and second image detectors 14 and 16 (x2, y2, z2) and
The first center line La of the DUT 10 in the XYZ coordinate system is calculated (step 180). This is repeated for each center point b, c to obtain each center line La of the DUT 10.
, Lb, Lc are calculated (step 190).

Therefore, the object 10 to be measured is placed on the flat surface 2, and the whole detector 12 and the first and second image detectors 14, 1 are placed.
It is possible to measure the shape of the object to be measured 10 with a simple configuration in which 6 is arranged, and with a simple operation of placing the object to be measured 10 bent into a three-dimensional shape on the plane 2. .

[0034]

[0035]

It should be noted, first, second scanner 18,20,3
Without providing the second and the second, the first and second image detectors can be connected to the X
The object to be measured on the plane 2 may be configured to be scanned by allowing mechanical movement parallel to the axis and the Y axis.
Then, the first and second image detectors may be moved for each measurement location of the object to be measured, image data may be obtained, and the processing from step 130 onward may be performed.

[0037]

Next, an embodiment of another scanner 60 having a configuration different from the first and second scanners 18, 20, 32 and 34 of the above-described embodiment will be described with reference to FIG. This scanner 60 is provided with one mirror 62, and this mirror 62 is rotatably supported by a substantially U-shaped rotary frame 64 by a rotary shaft 66 parallel to the mirror surface. The rotary shaft 66 is connected to the pulse motor 6 fixed to the rotary frame 64.
It is configured to be rotated by 8.

The rotary frame 64 is formed so as to be rotated by a pulse motor 70 that rotates around an axis orthogonal to the rotary shaft 66. This scanner 60 is arranged in place of the first and second scanners 18 and 20 of the first image detector 14, and the image projected on the mirror 62 is formed on the two-dimensional image pickup device 28 by the lens 30. In this way, the image data is output from the two-dimensional image pickup device 26. Also for the second image detector 16, this scanner 60 is arranged in place of the first and second scanners 32 and 34.

The first and second image detectors 14 and 16 provided with the scanner 60 are attached so that the rotation shaft 66 forms an angle of 45 degrees with the X axis and the Y axis, and the respective predetermined positions thereof. (X1, y1, z1), (x2, y2
, Z2), it can be carried out in the same manner as described above. By using the scanner 60, the device can be downsized.

Alternatively, a single image detector equipped with the scanner 60 and the two-dimensional image pickup device 26 is provided by a mechanical device (not shown) between the predetermined positions (x1, y1, z1) and (x2, y2, z2). It is also possible to move by a simple moving mechanism. At this time, when one image detector is at one predetermined position (x1, y1, z1), it functions as the first image detector 14, and when it is at the other predetermined position (x2, y2, z2), It functions as the second image detector 16 and can measure the shape of the DUT 10 in the same manner as in the above-described embodiment.

The present invention is not limited to the embodiments described above, and can be carried out in various modes without departing from the scope of the present invention.

[0043]

As described in detail above, the three-dimensional shape measuring apparatus for a long material according to the present invention is provided with the whole detector and the first and second screens.
It has a simple configuration with an image detector, and it can be measured on a flat surface.
Simply place a fixed object and you will not have to perform operations for subsequent measurements.
Calculate the center line for each straight part of the DUT without requiring
Can be bent into a three-dimensional shape with a simple operation.
It is possible to measure the shape of the processed object to be measured.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating a basic configuration of a three-dimensional shape measuring apparatus for a long material according to the present invention.

FIG. 2 is a schematic configuration diagram of a three-dimensional shape measuring apparatus for a long material according to the present embodiment.

FIG. 3 is a schematic configuration diagram of an image detector of the three-dimensional shape measuring apparatus for a long material according to the present embodiment.

FIG. 4 is a block diagram showing a configuration of an electric system of the three-dimensional shape measuring apparatus for a long material according to the present embodiment.

FIG. 5 is a flowchart showing an example of a shape measuring process executed in a control circuit of the three-dimensional shape measuring apparatus for a long material according to the present embodiment.

FIG. 6 is 2 detected by the first image detector of the present embodiment.
It is explanatory drawing which shows the image after a value-ized process.

FIG. 7 shows 2 detected by the second image detector of the present embodiment.
It is explanatory drawing which shows the image after a value-ized process.

FIG. 8 is an explanatory perspective view illustrating calculation of a centerline from a plane including a projection centerline according to the present embodiment.

FIG. 9 is an explanatory diagram illustrating calculation of an end point from the end of the measured object according to the present embodiment.

FIG. 10 is an explanatory diagram showing a display example of measurement results of the device under test according to the present embodiment.

FIG. 11 is a perspective view of a scanner according to another embodiment.

[Explanation of symbols]

M1, 10 ... M2, 12 ... Whole object detected
Vessel M3 ... central point detecting means M4,14 ... first image
Detector M5 , 16 ... Second image detector M6 ... Image control means M7 ... Projection calculation means M8 ... Center line calculation means 2 ... Plane 18 ... First scanner 20 ... Second scanner 40 ... Control circuit

Claims (1)

[Claims] 1. A whole inspection for detecting an entire object to be measured, which is obtained by bending a long material placed on a plane, as a two-dimensional image.
Based on the source and the two-dimensional image from the global detector
Center point detecting means for detecting the center point of the straight line portion of the DUT and
And capable of scanning on the plane, the object to be measured.
Some measurement points are magnified than the image of the whole detector
The first and second image detectors for detecting a two-dimensional image
It is placed at a predetermined position with a predetermined distance and the center point
Based on the center point detected by the detection means, the
Scan the plane by controlling the first and second image detectors
And image control means for detecting the linear portion of the measured object
And projection calculation means for calculating projection centerlines of the measurement object on the plane from the images of the measurement object by the first and second image detectors, the calculated projection centerlines, and Center plane calculating means for calculating respective planes including these from the positions of the first and second image detectors and calculating a line of intersection of the two planes as a center line of the object to be measured. 3D measuring device for long materials.