JPH03226617A - Measuring apparatus of three dimensional form - Google Patents

Abstract

PURPOSE:To simplify the photographing process of a spot image by computing the coordinates of the position of the spot image on an object to be measured from the rotary angles of a first and a second mirrors and the distance between the axial centers thereof when the spot image is formed at a predetermined position. CONSTITUTION:When an operating part 15 is manipulated, a driving part 14 is driven to rotate a rotary structural part 9a and further a mirror 4. As a result, a laser light 2 is projected to an object 6 to be measured and a spot image 7 is formed on the object 6. Then, a mirror 5 is rotated and the spot image 7 is reflected by the mirror 5. Accordingly, the spot image is formed on an optical sensor 8a. The position of the spot image is detected by the sensor 8a and converted via an image position detecting part 13 to the information of the image forming position and input to a controlling part 10. Based on the information of the image forming position, the mirror 5 is rotated and, when the spot image formed on the sensor 8a reaches the predetermined position, the rotary angle of each mirror 4, 5 is obtained. The coordinates of the position of the spot image 7 on the object 6 are operated from the rotary angles and the distance between the axial centers 4a, 5a of the mirrors 4, 5.

Description

Detailed Description of the Invention 3. Field of Industrial Application] The present invention relates to an improvement of a three-dimensional shape measuring device using a spot projection method, and more specifically, the present invention relates to an improvement of a three-dimensional shape measuring device using a spot projection method.
) Can facilitate image capture processing and initial setting of the mounting device 3
This invention relates to a dimensional shape measuring device.

[Prior Art] Conventionally, various measurement methods such as an AM optical phase difference measurement method and a spot light projection method have been proposed as methods for non-contact measurement of the three-dimensional shape of an object to be measured. Among them, the spot light projection method, which projects a spot light onto the object to be measured, uses the principle of triangulation, as described below, and is known to be highly reliable and capable of high-precision measurements. There is.

FIG. 7 shows an example of a three-dimensional shape measuring device using the spot light projection method.

This three-dimensional shape measuring device 51 has a groove 7 on an object 52 to be measured.
) A theotrite 54 that projects light (for example, laser light) 53 at a variable projection angle, and a TV camera 56 that captures a spot image 55 projected onto the object to be measured 52.

The theodolite 54 and the TV camera 56 are the eighth
As schematically shown in the figure, they are arranged at a predetermined distance (for example, L).

A spot image 55 formed by the laser beam 53 projected from the seven-dimensional light 54 is captured by the TV camera 56 at a predetermined point on the imaging surface of the TV camera 56 (
The TV camera 56 is rotationally controlled based on the image processing information of the image processing device 57 so as to come to the spot image 55 (for example, the center point), and the same spot image 55 is tracked.

Then, the projection angle of the laser beam 53 (for example, the 8th
θ1 shown in the figure. φ+), the imaging angle of the spot image captured by the TV camera 56 (θ2.φ, in the figure), and the spot on the object to be measured 52 whose origin is the midpoint 58 at the same distance from the above distance value. Position coordinates of image 55 (X, Y, Z
) is determined based on the principle of triangulation, for example, according to the following equation, and the three-dimensional shape of the object to be measured 52 is measured.

(theory θ2 + noodle θf) as a result θ2 101 (till θ2 − tuθ1) sin θ2 Also,
When the theodore, light 54, and TV camera 56 are installed, the distance is calibrated as an initial setting, for example, as shown below. i.e. accurately calibrated length. A standard standard is installed near the object to be measured 52, and the theodolite 5 is
4 and the azimuth deviation ((θ1', φ1', θs', φ2') of both end points of the standard standard when viewed from the TV camera 56, and (
θ1−φ802″, φ2″) is measured.

Then, by substituting these azimuth angles into the equations for X, Y, and Z, the following equation is obtained: r-o'=(xce+'', 192', +111')
X (19+"*θx', d +') + (Y (θ, ゛, θ2゛, φ+'), Y (θl#, θ2#, φ1") +
(Z (θ+', θz', #t') Z (θl',
θz"7+"), the distance used as the above reference is calibrated.

The three-dimensional shape measuring device 51 described above is, for example, 5ICE'
89. Proceedings of the 28th Academic Conference, JS7-1.

It is disclosed on page 69.

[Problem to be solved by the invention]

As described above, in the conventional three-dimensional shape measuring device 51, it takes time and effort to prepare a standard of length Lo for initial setting and measure the azimuth angle of both end points of the standard, which reduces measurement work efficiency. At the same time, the workers are also limited to skilled workers who have acquired measurement techniques.

Furthermore, T is used to capture the spot image projected onto the object to be measured.
The V camera 56 has two-axis rotational freedom, and the TV
Camera 560 rotation control processing is complicated.

Therefore, the present invention has been made for the purpose of providing a three-dimensional shape measuring device that simplifies the imaging process of the sponode image projected onto the object to be measured and facilitates the initial setting of the device. be.

[Means to solve the problem]

In order to achieve the above-mentioned object, the present invention provides a
) Projecting light, capturing a spot image projected onto the object to be measured with an imaging surface spaced a predetermined distance from the projecting point, and determining the projecting angle of the spot light and the uplift angle of the spot image. And the position coordinates of the spot image on the object to be measured are determined from the distance between the light projection point and the imaging plane /i! In a three-dimensional shape measuring device for calculating a shape, a light source that emits a spot light, and a rotatable shaft S that is provided on the optical axis of the spot light from the light source and that is rotatable about an axis perpendicular to the optical axis of the spot light are provided. A first lamp is attached to the light source and reflects the spot light projected from the light source.
a mirror, and a second mirror, which is provided on the opposite side of the first mirror with the light source in between, and is rotatably mounted around an axis that is parallel to the axis of the first mirror and is integrally configured with two mirrors. an optical sensor that is provided integrally with the light source and that captures a spot image reflected by the second mirror and detects the position of the captured spot image; Projecting a spot image onto the object to be measured, rotating the second mirror to form the spot image onto the optical sensor, and when the image forming point is at a predetermined position. The rotation angle of the first mirror, the rotation angle of the second mirror, and the axis of the first mirror and the second mirror.
A three-dimensional shape that calculates the position coordinates of the spot image on the object to be measured from the distance between it and the axis of the mirror! The present invention is configured as a three-dimensional shape measuring device characterized by comprising a ji calculation means.

[This three-dimensional shape measuring device is configured such that the first mirror and the second mirror are parallel and integrated with the light source in between, as described above, so that the reference distance for triangulation [ The distance between the axis of the first mirror and the axis of the second mirror constituting the mirror is always constant.

Therefore, in the initial setting of this three-dimensional shape meter ♂lI' device, the trouble of measuring and calibrating the reference path ML, which has been conventionally performed, can be omitted.

In addition, in this three-dimensional shape measuring device, the first mirror is rotated to project a spot image onto the object to be measured, and the second mirror is rotated to form the same spot image on the optical sensor.
When the image forming point is at a predetermined position, the rotation angle of the first mirror, the rotation angle of the second mirror, and the axis between the axis of the first mirror and the axis of the second mirror are determined by three-dimensional shape calculation. The position coordinates of the spot image on the object to be measured are calculated from the distance, and the three-dimensional shape of the object to be measured is determined.

The image forming process in which the image forming point is set at a predetermined position can be performed by only one-axis rotation process of the second mirror as described above, and is therefore easier than the conventional two-axis rotation process method.

SX Example] Hereinafter, examples embodying the present invention will be described with reference to the accompanying drawings to provide an understanding of the present invention.

In addition, the following example is an example embodying the present invention,
It is not intended to limit the technical scope of the present invention.

Fig. 1 is a block diagram showing a three-dimensional shape measuring device according to an embodiment of the present invention, Fig. 2 is a block diagram of an example of the same three-dimensional shape measuring IT with a movement function added, and Fig. 3 is a block diagram showing a three-dimensional shape measuring device according to an embodiment of the present invention. Shape measuring device! Explanatory diagram schematically showing a 4-split optical sensor that can be used for
5(a), 5(b), and 5(C) are schematic diagrams showing variations in the arrangement of the light source and light condensing section of the same three-dimensional shape measuring device. A schematic diagram showing an example using a mirror, Figure 6 shows the light source and first
FIG. 3 is a schematic diagram showing an example in which mirror functions are integrated.

As shown in FIG. 1, this three-dimensional shape measuring device 1 includes a lens (not shown) that emits a spot light (for example, a laser beam) 2.
The light source #3 is attached to the rotating structure 9° of the three-dimensional shape measuring device 1.

The light source 3 in the rotating structure 9a is integrated with the optical axis 2a of the laser beam 2. The axis 4a perpendicular to
A first mirror 4 is attached so as to be rotatable about the center.

Also, on the opposite side of the first mirror 4 across the light s3, the first
Axis center of mirror 4 4. A second mirror 5 is rotatably mounted about an axis 5 parallel to the second mirror 5.

The above light #3 and the first mirror 4. The above-mentioned rotating structure section 9 that integrally houses the second mirror 5 and the like. Second, it is rotatably mounted on the support structure 9b of the three-dimensional shape measuring device 1 as shown by arrow A (FIG. 1).

When the laser beam 2 is projected from the light #3, the laser beam 2 is reflected by the first mirror 4, and an image 7 of the object to be measured 6 is formed. This sport,・1・image 7
is reflected by the second mirror 5, and the rotating structure 9
The light is condensed into a condensing unit 8 consisting of a lens (non-flash), etc., which is integrally attached to the light source 3 in the interior of the light source 3.

The light is collected by the light collecting section 8, and an optical sensor 8 is provided on the light collecting section 8. It is imaged above.

The optical sensor 8a is composed of, for example, a PSD (Position Sensitivity Detector) or the like that can detect the position of the imaged spot image.

The control circuit of this three-dimensional shape measuring device 1 is composed of a control section 10 consisting of a microcomputer CPtJ, etc., and is connected to a first drive section 11. A second drive unit 12 that rotationally drives the second mirror 5. Image position detection section 13 that processes the output signal from the optical sensor 81. and a third drive section 14 that rotationally drives the rotation structure section 91. An operating section 15 for issuing various commands to the three-dimensional shape measuring device 1 is also connected.

The rotation angle of the first mirror 40 and the rotation angle of the second mirror 5 are detected by the first encoder 16 and second encoder 17 built in the first drive section 11 and the second drive section 12, and the control section 10 is input.

In addition, the rotating structure section 9. The rotation angle is detected by the third encoder]8 built in the third drive section 14,
It is input to the control unit 10.

The reference path # for triangulation of this three-dimensional shape measuring device 1 is as follows:
The axis 48 of the first mirror 4 and the axis 50 of the second mirror 50. This distance is always constant.

Therefore, in the initial setting of this three-dimensional shape measuring device 1, there is no need to calibrate the measurement of the reference path ML, which has been done in the past.

That is, in this three-dimensional shape measuring device Fl, the three-dimensional shape measuring device Fl is installed so that a spot image 7 of the laser beam 2 can be formed on the object to be measured 6! You can immediately start measuring the three-dimensional shape shown below just by doing this.

Next↓The three-dimensional shape measuring process of this three-dimensional shape measuring device 10 will be explained.

When the operation section 15 is operated in a predetermined manner, the third drive section 4 is driven to rotate the rotating structure section 9a, and the first mirror 4 is further rotated to project the laser beam 2 onto the object to be measured 6. , a spot image 7 is projected onto the same object to be measured 6.

Then, the second mirror 5 is rotated so that the spot image 7 is reflected by the second mirror 5, and the spot image is formed on the optical sensor 8□.

The position of the formed spot image is determined by the optical sensor 8□
The spot image is detected by the image position detecting section 13, converted into spot image forming position information, and input to the control section 10.

Based on the image formation position information, the second mirror 5 is further controlled to rotate, and when the spot image formed on the optical sensor 81 is at a predetermined position (for example, the center point of the optical sensor 81), the second mirror 5 is rotated. 2 the rotation angle of the mirror 5 and the first
The rotation angle of mirror 4 is determined.

The imaging process for setting the spot image formed on the optical sensor 81 at a predetermined position is carried out by one of the second mirrors 5 as described above.
Since only axis rotation processing is required, it is easier and faster processing is possible than the conventional two-axis rotation processing method.

Then, the rotation angle of the first mirror 4 obtained above, the second
The rotation angle of the mirror 5 and the axis 4 of the first mirror 4. The coordinates of the spot image 7 on the object to be measured 6 are calculated from the distance between the center axis 5a of the second mirror 5 and the axis 5a of the second mirror 5.

Thereafter, similarly, the rotation of the rotating structure 9a, the first mirror 4, and the second mirror 5 are sequentially controlled to determine the three-dimensional shape of the entire object to be measured 6.

The above-mentioned first mirror 4 is rotated to project a spot image 7 onto the object to be measured 6, and the second mirror 5 is rotated to form the above-mentioned spot image on the optical sensor 8a. is at a predetermined position, the rotation angle of the first mirror 4, the rotation angle of the second mirror, and the first mirror 4 are changed. 2nd mirror 4.5
Axial center of 4. ．． A means for realizing the function of calculating the position coordinates of the spot image from a distance of 5 degrees is an example of a three-dimensional shape/ji calculating means.

Note that the optical sensor 8 of the above embodiment. PSD used in
Since the object to be measured is large, the distance between the three-dimensional shape measuring device 1 and the object 6 becomes longer and the light of the spot image 7 becomes weaker, the output current value becomes smaller and the position becomes smaller. Detection resolution decreases.

Therefore, the PSD may be replaced with, for example, a 4-split optical sensor 19 schematically shown in the 30th section.

This 4-split optical sensor 19 is composed of, for example, a silicon photodiode, and has four independent detection surfaces 19. , +9b, 19c19, and I, and the received light intensity of each surface can be detected.

Therefore, the position of the spot image formed on the surface of the 4-split optical sensor 19 is 2 (1
The same 4-split optical sensor 1 can process information as well.
It is possible to control the output signals from each side of 9 to have a predetermined balanced Q (for example, all equal).

Therefore, when this 4-split optical sensor 19 is used, even if the object to be measured is a large object such as a building structure, a car body, a ship, a pressure vessel, etc., and the light intensity of the image is weak, a constant It is possible to detect the same spot image (- position) with high resolution.

In addition, FIG. 2 shows the three-dimensional shape measuring device l as shown in FIG.
．． 21, etc., to configure a three-dimensional shape measuring device].

In this way, the three-dimensional shape measuring device 1 can be moved even more easily.

The three-dimensional shape measuring device 1.1a described above was designed to require a small installation space, but if there is sufficient space for installation, the light source 3 and the condenser can be The arrangement of the light section 8, etc. may be changed.

FIG. 4(a) shows an example in which the three-dimensional shape measuring device 1b is constructed by alternately arranging the light sources 3 and the condensing parts 8. In addition, FIG. 4 (bl is the light source 3 and the light condensing part 8
This is an example in which a three-dimensional shape measuring device 1c is constructed by arranging the three-dimensional shape measuring apparatus 1c. Furthermore, as shown in FIG. 4(C), the three-dimensional shape measuring device IJ is configured with the two light sources 3:8 and the condenser 8 so that the light emitting and light receiving directions O angular changes are different (for example, perpendicular to each other). This is an example.

Further, the light source 2 may be constructed using a mirror itself.

For example, FIGS. 5(a) and 5(b) respectively show the light source 3
and one mirror (Ml
), three-dimensional shape measuring devices 1e and I+ are shown. Furthermore, FIG. 5(C) shows that there are two mirrors (Ml
, M2), the three-dimensional shape measuring device 1g is shown.

Note that the functions of the light #3 and the first mirror 4 may be integrated. In this case, just as the projection angle of the laser beam 2 can be changed by rotating the first mirror 4, it is also necessary to rotate the light a3 as shown below.

In FIG. 6, in order to be able to change the projection angle of the laser beam 2 from the light source 3 attached to the rotary structure 9a, the rotary structure 9a itself is arranged with an axis Z perpendicular to the optical axis 2a. ↓This configuration allows the above function to be achieved by rotating the arrows B and C4 as shown in the same way as the first mirror 4.
- This shows the 3D shape measurement official IL.

〔Effect of the invention〕

According to the present invention, a spot light is projected onto an object to be measured, a spot image projected onto the object to be measured is captured on an imaging surface separated by a predetermined distance from the projection point, and the projection angle of the spot light is determined as described above. A three-dimensional shape measuring device that calculates positional coordinates of a spot image on an object to be measured from an imaging angle of the spot image and a distance between the light projection point and the imaging surface, the device comprises: a light source that projects a spot light; a first mirror that is provided on the optical axis of the spot light from the light source, is rotatably attached around an axis perpendicular to the optical axis of the spot light, and reflects the spot light projected from the light source; a desk provided on the opposite side of the first mirror across the light source, and a second mirror mounted rotatably about an axis that is parallel to and integrally formed with the axis of the first mirror; an optical sensor that is provided integrally with the light source and that captures a spot image reflected by the second mirror and detects the position of the captured spot image; The spot image projected onto the object to be measured is focused on the optical sensor by rotating the second mirror, and when the image forming point is at a predetermined position, the spot image projected onto the object to be measured is focused on the optical sensor. three-dimensional shape calculation for calculating the positional coordinates of the spot image on the object to be measured from the rotation angle of the mirror, the rotation angle of the second mirror, and the distance between the axis of the first mirror and the axis of the second mirror; A three-dimensional shape measuring device is provided, characterized in that it comprises means.

Therefore, the spot image capturing process can be simplified and the initial setting of the apparatus can be facilitated.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a three-dimensional shape measuring device according to an embodiment of the present invention, Fig. 2 is a block diagram of an example of the same three-dimensional shape measuring device with a movement function added, and Fig. 3 is a block diagram showing the same three-dimensional shape measuring device. Explanatory diagram schematically showing a 4-split optical sensor that can be used in a shape measuring device, Figures 4 (a), (b), (C)
5(a), 5(b), and 5(C) are schematic diagrams showing variations in the arrangement of the light source and light condensing section of the same three-dimensional shape measuring device. A schematic diagram showing an example using a mirror, Figure 6 shows the light source and first
FIG. 7 is a schematic diagram showing an example of integrating mirror functions; FIG. 7 is a block diagram showing an example of a conventional three-dimensional shape measuring device; FIG.
The figure shows the same three-dimensional shape measuring device, the Seven Odolite, and a TV camera! It is an explanatory schematic diagram showing a relationship. [Explanation of symbols] ], 11+t,, lc, la, le, 111t, I
h... Three-dimensional shape measuring device 2... Laser light (spot light) 3... Light source 4... First mirror, 4. ... Axis center 5 of the first mirror
...Second mirror 5□...Axis center of second mirror 6.
...Object to be measured 7...Spot image 8...Condensing section 8a...Optical sensor lO...Control section 16...First encoder 17...Second encoder 18...Third Encoder 19... 4-split optical sensor No. 2 @ 21 3 Redundancy Fig. 1 7 2 Fig. 8 % Fig. 7 1

Claims (1)

[Claims] 1. A spot light is projected onto the object to be measured, and a spot image projected onto the object to be measured is captured with an imaging surface separated by a predetermined distance from the projection point, and the spot light is projected onto the object to be measured. In a three-dimensional shape measuring device that calculates the positional coordinates of a spot image on an object to be measured from a projection angle, an imaging angle of the spot image, and a distance between the projection point and the imaging surface, the spot light is projected. a light source provided on the optical axis of the spot light from the light source, rotatably mounted around an axis perpendicular to the optical axis of the spot light, and reflecting the spot light projected from the light source; a first mirror, which is provided on the opposite side of the first mirror across the light source and is rotatably mounted around an axis that is parallel to and integrally formed with the axis of the first mirror; a second mirror; an optical sensor that is provided integrally with the light source and that captures a spot image reflected by the second mirror and detects the position of the captured spot image; and a second mirror that rotates the first mirror. A spot image is projected onto the object to be measured, the spot image projected onto the object to be measured is focused on the optical sensor by rotating the second mirror, and the image forming point is at a predetermined position. Then, the position coordinates of the spot image on the object to be measured are calculated from the rotation angle of the first mirror, the rotation angle of the second mirror, and the distance between the axis of the first mirror and the axis of the second mirror. A three-dimensional shape measuring device comprising three-dimensional shape calculation means.