JP2002107128A - Shape-measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a marker for specifying parts which enables also the position of the specific part of an object to be detected, when a three- dimensional shape of the object to be measured is measured by a light-section method. SOLUTION: In measuring a shape, in which the shape of the object to be measured is measured by projecting a slit light to the object and observing the slit light projected to the object by an imaging element, and the measured result is displayed using a curve by changing colors, according to the luminance of the slit light observed by the imaging element, the marker for specifying parts which is attached to a predetermined part of the object with the aim of detecting the position of the prescribed part of the object is like a sheet, having a color for reflecting the slit light painted to an outside face of a central part and a color for absorbing the slit light, painted to the outside face of the circumference of the central part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention measures the shape of an object by projecting slit light onto the object and observing the slit light projected on the object with an image sensor. When performing shape measurement such as displaying a curve by changing the color according to the brightness of the slit light observed by the image sensor, a predetermined position of the target object is detected for the purpose of detecting a position of a predetermined portion of the target object. And a part identification marker attached to the part.

[0002]

2. Description of the Related Art In general, the size of a shoe is usually expressed by the length from the heel to the fingertip. It is. When trying to make shoes according to the shape of each person's foot, it is necessary to measure the three-dimensional shape of the foot, but at present, using a measure, foot length, foot width, foot position (around the foot)
It only measures the size of limited parts such as.

[0003] On the other hand, the slit light is projected on the object to be measured, and the shape of the object to be measured is measured by observing the slit light projected on the object with an image sensor. 2. Description of the Related Art A shape measuring device that measures a three-dimensional shape of an object is known.

[0004] When manufacturing shoes corresponding to the shape of the foot, it is necessary to measure the height of the arch, the position of the instep, and the like.

[0005] The arch height is measured, for example, as the height from the floor on which the foot is placed to the navicular. The instep position is measured, for example, as the height from the floor on which the foot is placed to the first cuneiform.

Therefore, in order to measure the height of the arch, the position of the instep of the foot, and the like, it is necessary to measure the positions of the scaphoid, the first wedge, and the like. However, since the positions of the scaphoid, the first cuneiform bone, and the like can be recognized by tactile sensation, these positions cannot be specified from the measurement results of the three-dimensional shape of the foot.

[0007]

SUMMARY OF THE INVENTION According to the present invention, when a three-dimensional shape of an object to be measured is measured by a light-section method, a portion specifying a position of a specific portion of the object to be measured can be detected. It is an object to provide a marker for use.

[0008]

A part identification marker according to the present invention projects slit light on an object to be measured, and observes the slit light projected on the object to be measured by an image pickup device. When measuring the shape and performing shape measurement such as displaying the measurement result as a curve by changing the color according to the brightness of the slit light observed by the image sensor, the position of a predetermined portion of the measured object is detected. In the part identification marker to be affixed to a predetermined part of the measured object for the purpose, it is sheet-shaped, the outer surface of the central part is painted with a color that reflects slit light, and the outer peripheral surface around the central part is slit. It is characterized by being painted in a color that absorbs light. Note that the “curve” in “displaying as a curve by changing the color according to the brightness of the slit light observed by the image sensor” is actually formed by a group of points.

Preferably, a hole is formed at the center of the center of the site specifying marker. Alternatively, a projection may be formed at the center position of the center of the site identification marker. Alternatively, a protruding member may be fixed to the center position of the center of the site specifying marker.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

[A] Description of shape measuring device

[A-1] Description of Schematic Configuration of Shape Measurement Apparatus

FIG. 1 shows a schematic configuration of a shape measuring apparatus.

An oblong guide rail 204 is fixed to the measuring table 201, and a foot 100 as an object to be measured is placed in a region surrounded by the guide rail 204. In addition, a column 202 that can be attached to and detached from the table 201 is attached to the table 201, and a horizontal bar 203 is attached to the upper part thereof.

The shape measuring device performs a measurement head 10 which can be moved on a guide rail 204 by a measurer, stereo cameras 21 and 22 attached to both ends of a horizontal bar 203, control thereof, and various calculations. And a control device 30 including a personal computer. Each of the imaging lenses of the stereo cameras 21 and 22 is provided with a bandpass filter 23 for selectively transmitting a frequency band of light emitted by the measurement head marker 14 shown in FIG.

[A-2] Description of Schematic Configuration of Measuring Head

FIG. 2 shows a schematic configuration of the measuring head 10.

The measuring head 10 has a rectangular parallelepiped casing 11 having a front opening, one CCD camera 12 and a slit light source 13 housed in the casing 11, and six LED light sources 14a provided on the upper surface of the casing 11. ~ 1
And a measurement head marker 14 made of 4f. As the slit light source 13, a semiconductor laser is used.

The six Ls constituting the measuring head marker 14
The ED light sources 14a to 14f are not point-symmetrically arranged to specify the direction of the measurement head 10, but are arranged line-symmetrically with respect to the center line of the measurement head 10. Here, LED light sources 11b, 11c, 11
Five points d, 11e, and 11f are arranged so as to form a rectangle, and an LED light source 11a is arranged at the center of gravity of the five points.

In order to measure the position and direction of the measuring head 10 in a three-dimensional space, it is sufficient if at least three LED light sources are used as a measuring head marker. By using this, the measurement accuracy of the position and direction of the measurement head 10 is improved in a least square manner.

The measuring head 10 is movably mounted along a guide rail 204 by a support mechanism (not shown). The measuring head 10 is a measuring head 10 based on a predetermined position on the guide rail 204.
Is provided with an encoder 16 for detecting the position of.
The output of the encoder 16 is input to the control device 30.

[A-3] Explanation of measurement principle of shape measuring device

FIG. 3 shows the measuring principle of the shape measuring device.

The coordinates of a measurement point A are measured using the measurement head 10 which is moved on the guide rail 204 by a measurer. The measured coordinates are referred to as coordinates (X
c, Yc, Zc). This coordinate system is used for measuring head 1
This is a coordinate system that moves with the movement of 0.

On the other hand, the shape of the DUT 100 is represented by a fixed coordinate system, and this coordinate system is called world coordinates. The coordinates of the measurement point measured by the measurement head 10 in the world coordinate system are defined as (Xw, Yw, Zw). Since the shape of the DUT 100 needs to be described in the world coordinate system, the coordinates (Xc, Yc, Z) of the measurement point A measured by the measurement head 10 in the coordinate system of the center of the measurement head.
c) is transformed into a world coordinate system. This conversion is performed using the rotation matrix R representing the movement of the measuring head 10 and the translation vector t based on the following equation 1.

[0026]

(Equation 1)

Accordingly, the coordinates (Xc, Yc, Zc) of the center of the measuring head in the coordinate system are determined by determining the position and direction of the measuring head 10 in the world coordinate system as the rotation matrix R and the translation vector t. (Xw, Yw, Zw).

[A-4] Description of the shape measurement processing procedure by the shape measurement device

The shape measurement by this shape measuring device is executed according to the following processing procedure.

First, prior to actual shape measurement, pre-processing is performed.

(1) First Step (Preliminary Processing): The control device 30 associates information about each measurement position of the measurement head 10 in the world coordinate system with the output value of the encoder 16 at each measurement position of the measurement head 10. Is stored in a memory (not shown) mounted on the PC.

After the preliminary processing, a shape measurement processing including the following second and third steps is performed. The shape measurement processing is performed by supporting columns 20 that support stereo cameras 21 and 22.
2 can be removed from the measuring table 201.

(2) Second step: stereo camera 2
After removing the support 202 supporting the first and second 22 from the measurement table 201, the coordinates of the measurement point on the DUT 100 in the camera coordinate system are obtained using the measurement head 10.

(3) Third step: Based on the information on the position of the measuring head 10 in the world coordinate system, the coordinates of the measurement point on the object to be measured in the camera coordinate system are converted into coordinates in the world coordinate system.

Hereinafter, each of these steps will be described.

[A-5] Description of First Step

FIG. 4 is a flowchart for explaining the processing procedure of the first step.

First, the measuring head 10 is connected to the guide rail 20.
4 (step 1), and the output value of the encoder 16 at that position is stored in the memory of the control device 30 (step 2).

Next, the coordinates of the marker 14 provided on the measuring head 10 in the world coordinate system are measured by the stereo cameras 21 and 22. Since this position measurement method is well known as a stereo method, its description is omitted (step 3).

Next, the coordinates of the LED light sources 14a to 14f constituting the marker 14 in the camera coordinate system are respectively represented by (Xc
i, Yci, Zci), and the stereo camera 2
Each LED light source 14a-14 measured by 1 and 22
Let the coordinates of f in the world coordinate system be (Xwi,
Ywi, Zwi). Here, i is 1, 2,. Each coordinate (Xci, Yci, Zci) of the camera coordinate system of each of the LED light sources 14a to 14f is known.

A rotation matrix R and a translation vector t representing the movement of the measuring head 10 are obtained as a matrix R and a vector t satisfying the following equation 2 (step 4). Then, the obtained matrix R and vector t are stored in the memory in association with the output value of the encoder 16 previously stored in the memory (step 5).

[0042]

(Equation 2)

Then, the measuring head 10 is moved to the guide rail 2
04, and repeat the processing of steps 2 to 5 for all the measurement positions (step 6,
7). Thereby, table data in which the output value of the encoder 16 is associated with the rotation matrix R and the translation vector t at that position is generated and stored in the memory of the control device 30.

[A-6] Description of Second Step

FIG. 5 shows a method for measuring the position of a measuring point by the measuring head 10.

As shown in FIG. 5, the camera coordinate system is C
With the optical center of the CD camera 12 as the origin, the optical axis direction is Zc
This is a coordinate system in which the horizontal axis of the CCD camera 12 is the Xc axis and the vertical direction of the CCD camera 12 is the Yc axis. CCD
The image plane S of the camera 12 is located at a focal distance f from the origin. That is, the image plane S is a plane parallel to the Xc-Yc plane and Zc = f.

The position measuring method itself by the measuring head 10 is a known measuring method called a light section method. A predetermined point on a line on the surface of the DUT 100 on which the slit light from the slit light source 13 is irradiated is defined as a measurement point A.

The coordinates of this measurement point A in the camera coordinate system are (Xc, Yc, Zc), and the coordinates of the observation point A ′ corresponding to the measurement point A on the image plane S are (Xs, Ys, f). age,
The equation of the plane representing the slit light is expressed as A _L Xc + B _L Yc +
It is assumed that C _L Zc + D _L = 0. The coordinates (Xs,
F in (Ys, f) is known as the focal length of the CCD camera 12, and (Xs, Ys) is obtained from the pixel position of the slit light observed on the image plane.

The equation of the plane representing the slit light is obtained by calibrating the measuring head 10. Therefore, X
By solving a simultaneous equation represented by the following Expression 3 with c, Yc, Zc, and α as unknowns, (Xc, Yc, Zc)
Is required.

[0050]

(Equation 3)

This processing is performed by the control device 30 based on the output of the CCD camera 12.

[7] Description of Third Step

In the third step, first, the encoder 16
, The corresponding rotation matrix R and translation vector t are read from the memory of the control device 30.

Next, based on the obtained rotation matrix R and the translation vector t, the coordinates (Xc, Yc, Zc) of the measurement point on the foot 100 in the camera coordinate system obtained in the third step.
To the coordinates (Xw, Yw, Zw) in the world coordinate system.

Then, the measuring head 10 is moved to the guide rail 2.
The second step and the fourth step are performed for all observation positions on the guide rail 204 while moving along the
By repeating the process of the step, the coordinates (Xw, Yw, Yw,
The shape of the foot 100 is obtained as a set of Zw).

The obtained three-dimensional shape of the foot is shown in FIG.
As shown in FIG. 5, the display is made on the monitor of the control device 30 by a plurality of curves along the three-dimensional shape of the foot. In the above shape measuring device, each curve representing the three-dimensional shape of the foot is displayed in a different color depending on the brightness of the slit light when the slit light corresponding to the curve is detected in the second step. You. The width of each curve representing the three-dimensional shape of the foot is displayed in a width corresponding to the width of the slit light when the slit light corresponding to the curve is detected in the second step.

[B] Description of Markers for Displaying Predetermined Locations of Measured Object (hereinafter referred to as site identification markers)

As described in the prior art, when manufacturing shoes according to the shape of the foot, it is necessary to measure the height of the arch, the position of the instep of the foot, and the like. The arch height is measured, for example, as the height from the floor on which the foot is placed to the navicular. The instep position is measured, for example, as the height from the floor on which the foot is placed to the first cuneiform.

Therefore, the arch height,
In order to measure the instep position and the like of the foot, it is necessary that the positions of the scaphoid, the first wedge-shaped bone, and the like can be recognized on the image in which the three-dimensional shape of the foot is displayed.

Therefore, the scaphoid of the foot, which is the object to be measured,
In a state where a part identification marker is attached to a position such as a wedge-shaped bone,
It is conceivable to perform shape measurement. It is assumed that a sheet-shaped circular marker is used as the part identification marker.

When measuring the shape, there are a case where the socks are worn on the foot of the object to be measured and a case where the socks are not worn. In any case, when the color of the part identification marker is one color, the part identification marker is not extracted if it is the same as the ground color (skin color or sock color). Further, when a dark color that absorbs the slit light emitted from the measuring head 10 is used as the marker color, there is a problem that the marker is not extracted.

Therefore, in this embodiment, the following site identification markers are used.

[B-1] Description of Specific Example of First Part Identification Marker

FIGS. 7 and 8 show the first part identification marker 300. FIG.

The site identifying marker 300 has a circular sheet shape and includes a central circular area 300a and an annular area 300b around the circular area 300a. The outer surface of the circular region 300a is painted with a color that reflects the slit light. The outer surface of the annular region 300b is painted with a color that absorbs slit light. Part identification marker 30
A sticking member is applied to the inner side surface of 0 so that the marker can be stuck to the foot.

The pitch (measurement pitch) of the curve in FIG.
Assuming that the diameter is 2 mm, the diameter of the region specifying marker 300 is set to, for example, 15 mm, and the diameter of the circular region 300a is set to, for example, 8 mm.

When the slit light emitted from the measuring head 10 is, for example, red laser light, the outer surface of the circular area 300a is coated with a color that reflects the red laser light, for example, white, red, or the like. Can be In addition, the annular portion 300
The outer surface of b is coated with a color that absorbs red laser light, for example, blue, black, or the like.

Therefore, when the slit light emitted from the measuring head 10 is, for example, red laser light, the combination of the color of the outer surface of the circular region 300a and the color of the outer surface of the annular portion 300b is as follows. There are the following combinations.

(1) The color of the outer surface of the circular region 300a is white, and the color of the outer surface of the circular region 300b is black. (2) The color of the outer surface of the circular region 300a is white and
(3) The color of the outer surface of the circular area 300a is red, and
(4) The color of the outer surface of the circular area 300a is red, and
00b is blue on the outer surface

As described above, the central portion (circular region 300a)
When a part identification marker whose outer surface is painted with a color that reflects slit light and whose outer surface is painted with a color that absorbs slit light is used as a peripheral part (annular region 300b). Are not extracted at the time of shape measurement, and the central portion (circular region 300a) is extracted at the time of shape measurement. Therefore, on the display screen of the measurement result, the central portion (circular region 300a) of the part identification marker and the peripheral portion (circular region 300a) are displayed. Annular region 30
0b) can be recognized. Therefore, it is possible to detect the position of the part specifying marker on the display screen of the measurement result, that is, the position of the specific part.

[B-2] Description of Specific Example of Second Part Identification Marker

A specific part to be measured (the scaphoid, the first
In order to accurately place the part identification marker on the cuneiform bone, etc.,
In other words, it is preferable to reduce the size of the part identification marker so that the center of the part identification marker is located directly above the specific part. It is difficult to do.

The second part specifying marker is devised to accurately attach the part specifying marker to a specific part. That is, as shown in FIGS. 9 and 10, the second part specifying marker 301 is the first part specifying marker 30.
At the center of the center (circular region 300a) of the marker similar to 0, a hole 300c that can be recognized by the tactile sensation of a finger is formed.

[B-3] Description of Specific Example of Third Part Identification Marker

FIGS. 11 and 12 show a third part specifying marker 302. FIG. Third part specifying marker 3
Also in 02, as in the case of the second part identification marker 301, a device for accurately attaching the part identification marker to a specific part has been devised. That is, the third part specifying marker 302 has a protrusion 300d formed at the center of the center (circular area 300a) of the marker similar to the first part specifying marker 300 so as to be recognizable by the tactile sensation of the finger. ing. The projection 300d is formed by, for example, embossing used when forming Braille.

[B-4] Description of Specific Example of Fourth Site Identification Marker

FIG. 13 and FIG. 14 show the fourth part specifying marker 303.

The fourth part specifying marker 303 is provided at the center of the center part (circular area 300a) of the marker instead of the protrusion 300d of the third part specifying marker 302 so that the fourth part specifying marker 303 can be recognized by the tactile sensation of the finger. The projection member 300e is fixed.

[0079]

According to the present invention, when the three-dimensional shape of the object to be measured is measured by the light section method, the position of a specific portion of the object to be measured can be detected.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an appearance of a shape measuring device.

FIG. 2 is a perspective view showing a measuring head.

FIG. 3 is an explanatory diagram illustrating a measurement principle.

FIG. 4 is a flowchart illustrating a processing procedure in a first step.

FIG. 5 is an explanatory diagram illustrating a method of measuring a position of a measurement point by a measurement head.

FIG. 6 is a schematic diagram showing a display example of a three-dimensional shape of a foot obtained by the shape measuring device.

FIG. 7 is a plan view showing a first site identification marker 300.

FIG. 8 is a side view showing a first site identification marker 300;

FIG. 9 is a plan view showing a second part identification marker 301.

FIG. 10 is a sectional view taken along line XX of FIG. 9;

FIG. 11 is a plan view showing a third part specifying marker 302;

FIG. 12 is a sectional view taken along the line XII-XII of FIG. 11;

FIG. 13 is a plan view showing a fourth part specifying marker 303.

FIG. 14 is a side view showing a fourth part specifying marker 303.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Measurement head 12 CCD camera 13 Slit light source 14 Marker 16 Encoder 21 Stereo camera 22 Stereo camera 201 Measurement stand 204 Guide rail 300, 301, 302, 303 Site identification marker 300a Circular area 300b Annular area 300c Hole 300d Projection 300e Projection member

 ──────────────────────────────────────────────────の Continuing on the front page (72) Hiroaki Yoshida 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Shinpei Fukumoto 2-5-2 Keihanhondori, Moriguchi-shi, Osaka No. 5 Sanyo Electric Co., Ltd. F term (reference) 2F065 AA53 BB28 CC16 FF01 FF02 FF05 FF09 FF15 FF46 GG06 GG07 GG25 HH05 JJ03 JJ05 JJ26 MM09 QQ23 SS13 4F050 AA01 AA06 LA01 NA88

Claims (4)

[Claims] 1. A shape of an object to be measured is measured by projecting slit light onto the object to be measured and observing the slit light projected onto the object to be measured with an image sensor, and the measurement result is observed with the image sensor. When performing shape measurement such as changing the color according to the brightness of the slit light and displaying it as a curve, a part attached to a predetermined part of the measured object for the purpose of detecting the position of the predetermined part of the measured object In the identification marker, a sheet-like shape, a color that reflects slit light is painted on an outer surface of a central portion, and a color that absorbs slit light is painted on an outer surface around the central portion. Part identification marker to be set. 2. The part identifying marker according to claim 1, wherein a hole is formed at a central position of the central part. 3. The part identifying marker according to claim 1, wherein a projection is formed at a center position of the central part. 4. The site identifying marker according to claim 1, wherein a projecting member is fixed at a center position of the central portion.