JP2014163892A - Laser measurement system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser measurement system capable of measuring the posture (inclination direction, inclination angle) of an object to be measured with simpler configurations, in a smaller size, and at lower costs.SOLUTION: The laser measurement system includes: a laser measurement device 10 having laser measurement means capable of measuring a distance to a measurement point and displacement means capable of changing the direction and angle or position of the laser measurement means; an imaging device 20 for outputting the image data of a two-dimensional image obtained by imaging a surface WM to be measured; and control means 40. At least three measurement points are set such that a polygon is formed on the surface to be measured. The control means executes, to each of measurement points WP1 to WP3, processing of measuring an actual measured distance as a distance from the laser measurement means 12 to each measurement point by controlling the displacement means 11 such that each measurement point is irradiated with a laser beam, and calculates the inclination direction and inclination angle of the surface WM to be measured to a preliminarily set virtual reference surface on the basis of each measurement point and actual measured distance.

Description

  The present invention relates to a laser measurement system that includes a laser measurement device capable of measuring a distance of a measurement object to a measurement surface and an imaging device, and is capable of measuring the tilt state of the measurement surface.

In recent years, a measurement system has been put to practical use that can scan an entire shape of an object to be measured at high speed using an expensive laser sensor or the like, and can measure the object to be measured in three dimensions in a short time. The system is a very expensive system that has a very complex structure, is large, and costs several million yen.
For example, in the prior art described in Patent Document 1, an imaging unit provided with a CCD camera and a laser probe (laser measurement device) is driven in the XYZ directions so that each part of an LSI package having a fine structure can be measured with high accuracy. Thus, a non-contact three-dimensional measuring apparatus capable of scanning and measuring a minute displacement of a workpiece with high accuracy is disclosed.

Japanese Patent Laid-Open No. 11-351858

For example, if it is necessary to detect the posture of the object or level the object in the production line, it is sufficient to perform the inclination angle and leveling of the target measurement surface, and it is not necessary to measure the three-dimensional shape of the entire object. There is a case.
In such a case, the three-dimensional measuring apparatus described in Patent Document 1 is not preferable because it becomes an excessive facility having performance more than necessary for the application, and space, cost, and performance are wasted.
The present invention was devised in view of such points, and realizes measurement of the posture (tilt direction, tilt angle) of a measurement object with a simpler configuration and at a smaller size and lower cost. It is an object of the present invention to provide a laser measurement system capable of performing the above.

In order to solve the above problems, the laser measurement system according to the present invention takes the following means.
First, the first invention of the present invention is a laser measurement capable of measuring a distance to a laser spot where a laser beam irradiated onto the surface to be measured hits the surface to be measured. Displacement having at least one of: means, swiveling means capable of changing a direction and angle from the laser measuring means toward the surface to be measured, or moving means capable of moving the position of the laser measuring means with respect to the surface to be measured A laser measuring device, an imaging device that outputs image data of a two-dimensional image obtained by imaging at least the surface to be measured of the measurement object, image data from the imaging device, and the laser measuring unit And a control means for controlling the displacement means.
The outline shape of the measurement object and the outline shape of the surface to be measured are recognized in advance by the control means, and at least three measurement points are set on the surface to be measured so as to form a polygon. The measurement points are set by the control means or set by input from the user.
Then, the control means recognizes the measurement surface of the measurement object based on image data from the imaging device, and controls the displacement means so that the set measurement point is irradiated with laser light. Then, irradiating a laser beam from the laser measuring unit to measure an actually measured distance that is a distance from the laser measuring unit to the measuring point is performed for each of the measuring points, and each of the measuring points is measured. And the inclination direction and the inclination angle of the surface to be measured with respect to a preset virtual reference surface.

  According to the first aspect of the present invention, it is only necessary to measure each of the distances to at least three measurement points on the surface to be measured by the laser measurement device. It can be a device. Therefore, it is possible to realize a laser measurement system that can measure the posture (inclination angle) of an object (surface to be measured) with a simpler configuration, a smaller size, and a lower cost.

  Next, a second invention of the present invention is the laser measurement system according to the first invention, comprising a display means, wherein the measurement point scans the surface of the measurement object. Three or more are set on the surface of the object, and the control means measures the measured distance from the laser measuring means to each measurement point, and expresses each measurement point as a circle or polygon with a predetermined diameter. The display means displays the brightness or density of each circle or each polygon corresponding to each measurement point by decreasing the brightness or increasing the density as the measured distance or the distance based on the measured distance becomes longer. To display.

  According to the second invention, despite the relatively simple configuration, the measurement object is scanned, and the circle or polygon corresponding to the position of the measurement point is changed in luminance or density according to the distance. By changing and displaying, it is possible to assist the operator to grasp the shape of the measurement object sensuously.

  Next, a third invention of the present invention is the laser measurement system according to the first invention or the second invention, wherein the control means is set based on image data from the imaging device. The displacement means is controlled so that the position of the measurement point coincides with the position of the laser spot of the laser beam irradiated on the actual measurement target surface.

  According to the third aspect of the present invention, the laser spot can be easily and surely moved by moving the position of the laser spot to the measurement point while confirming the position of the actual laser spot on the surface to be measured based on the image data. To the measuring point.

It is a perspective view explaining the example of the whole structure of the laser measurement system of this invention. It is a figure explaining the example of a displacement apparatus. It is a flowchart explaining the example of the process sequence of a control means. (A) shows an example of image data in a state where the surface of the measurement object is scanned, and (B) represents each scanned measurement point with a circle (or polygon), and each circle (or polygon) according to the distance ( Or it is a figure which shows the example of the image data which changed the shading of each polygon).

EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated using drawing. In the figure showing the X axis, Y axis, and Z axis, the X axis, Y axis, and Z axis are orthogonal to each other, the Z axis indicates vertically upward, and the X axis and Y axis are in the horizontal direction. Is shown.
● [Overall configuration of laser measurement system 1 (Fig. 1)]
As shown in FIG. 1, the laser measurement system 1 includes a laser measurement device 10, an imaging device 20, and a control unit 40, and the laser measurement device 10 and the imaging device 20 are placed on the table 2. .

The laser measurement device 10 includes a support member 13 fixed to the table 2, a displacement means 11 held on the support member 13, and a laser measurement means 12 attached to the displacement means 11.
The laser measurement unit 12 can irradiate the laser beam toward the measurement point, and can measure the distance from the laser measurement unit 12 to the measurement point.
As shown in the example of FIG. 2 (A), the displacing means 11 is a turning means 11A capable of changing the direction and angle of the laser measuring means 12, or the laser measuring means 12 as shown in the example of FIG. 2 (B). It is at least one of moving means 11B capable of moving the position.
Note that the turning means 11A shown in FIG. 2A can change the direction of the laser measuring means 12 facing downward to an arbitrary direction, and the moving means 11B shown in FIG. 2B is an XY stage, for example. Yes, the position in the XY plane of the laser measurement means 12 directed downward can be moved to an arbitrary position. 2A and 2B, the description of the control means 40 is omitted.
FIGS. 1, 2A and 2B show an example in which laser light is irradiated from the laser measurement means 12 toward each of the measurement points WP1 to WP3 on the measurement target surface WM of the measurement object W. FIG. Yes.

The imaging device 20 includes a support member 23 fixed to the table 2 and an imaging means 22 (CCD camera or the like) held on the support member 23.
Further, the optical axis 22Z of the imaging means 22 is directed at least in the direction in which the measurement target surface WM of the measurement object W is imaged.
The color of the table 2 is preferably a color that is different from the measurement target W and can be easily removed as background from the image data.
Then, the imaging device 20 images the measurement target surface WM in the imaging area and outputs image data (in this case, two-dimensional image data) obtained by the imaging to the control unit 40.

The control means 40 is a personal computer, for example, and can take in image data from the imaging device 20 and control the displacement means 11 and the laser measurement means 12.
The image capturing apparatus 20 may output image data when receiving an image request signal from the control unit 40, or may sequentially output images at predetermined time intervals without receiving an image request signal from the control unit 40. Data may be output. In the present embodiment, an example in which image data is output when an image request signal from the control means 40 is received will be described.
The control unit 40 outputs a drive signal to the displacement unit 11 to displace the direction, angle, or position of the laser measurement unit 12, outputs a measurement start signal to the laser measurement unit 12, and a detection signal from the laser measurement unit 12. And the distance from the laser measurement means 12 to the measurement point can be obtained.

In the example of the present embodiment, the measurement object W is placed on the table 2. The measurement target surface WM of the measurement object W is inclined with respect to the table 2. Note that an inclination direction VT indicated by a two-dot chain line in FIG. 1 is a straight line orthogonal to the measurement target surface WM, and indicates an inclination direction and an inclination angle of the measurement target surface WM.
The laser measurement system 1 obtains the inclination direction and the inclination angle of the measurement target surface with respect to a preset virtual reference plane. In the description of the present embodiment, an example in which the surface of the table 2 is set as a virtual reference plane will be described. To do.
As described above, the laser measurement system 1 according to the present embodiment includes a relatively inexpensive laser measurement unit 12 having a function of measuring a distance to a measurement point, and a relatively low price capable of obtaining two-dimensional image data. The image pickup means 22, the control means 40 such as a personal computer, and the general displacement means 11 are realized with a very simple configuration. However, it has sufficient accuracy for use in obtaining the inclination direction and inclination angle of the measurement target surface WM of the measurement object W, and is extremely small and inexpensive compared to the system described in Patent Document 1. System.

[Processing procedure of control means 40 (FIG. 3)]
Next, the processing procedure of the control means 40 will be described using the flowchart shown in FIG.
In step S10, the control unit 40 outputs an image request signal to the imaging unit 22, takes in the image data from the imaging unit 22, and recognizes the measurement target W and the measurement target surface WM captured in the image data. The process proceeds to step S20. Note that the control means 40 stores the approximate shape of the measurement object W and the approximate shape of the measurement surface WM in advance in the storage means, and can recognize the measurement object W and the measurement surface WM in the image data. it can.

In step S20, the control means 40 sets at least three measurement points on the recognized measurement target surface WM so as to form a polygon, and proceeds to step S30. FIG. 1 shows an example in which three measurement points WP1 to WP3 are set so as to form a triangle on the measurement target surface WM. It is preferable to set three measurement points, and even when the measurement target surface WM is not flat, the inclination direction and the inclination angle of the plane including the three points on the measurement target surface can be obtained. In the description of the present embodiment, an example in which the measurement target surface WM is planar and there are three measurement points will be described.
If the position of the measurement point on the surface to be measured is stored in the storage unit in advance, the measurement point is automatically set on the actual surface to be measured from the control unit 40 that has recognized the surface to be measured WM as described above. be able to.
The measurement point may be set by input from an operator. The operator clicks a desired position on the surface to be measured by using an input unit such as a mouse while viewing the image of the surface to be measured WM displayed on the display unit of the control unit 40, and thereby sets the measurement point. It may be settable.

In step S30, the control unit 40 controls the displacement unit 11 and the laser measurement unit 12 to obtain each actually measured distance that is a distance from the laser measurement unit 12 to each measurement point, and proceeds to step S40.
The control means 40 outputs a drive signal to the displacement means 11 so that the laser beam from the laser measurement means 12 is irradiated to the measurement point WP1, changes the orientation or position of the laser measurement means 12, and then the laser measurement means 12 A measurement start signal is output to the image pickup means 22 and an image request signal is output to the imaging means 22. Then, the control means 40 takes in the detection signal from the laser measurement means 12, takes in the image data from the imaging means 22, and determines whether or not the position of the laser spot imaged in the image data matches the set measurement point WP1. Determine.
If the position of the laser spot does not coincide with the measurement point WP1, the difference between the position of the laser spot and the position of the measurement point WP1 is obtained, and the position is again displaced so that the position of the laser spot coincides with the position of the measurement point WP1. A drive signal is output to the means 11, a detection signal is taken in again from the laser measuring means 12, and image data is taken in from the imaging means 22.
When the position of the laser spot coincides with the measurement point WP1, an actual measurement distance L1 (distance from the laser measurement means to the laser spot) with respect to the measurement point WP1 is obtained based on the detection signal from the laser measurement means 12 at that time. And remember.
This operation is also performed for each of the measurement points WP2 and WP3, and the actual measurement distance L2 for the measurement point WP2 and the actual measurement distance L3 for the measurement point WP3 are obtained and stored.

In step S40, based on the obtained actual measured distances, the inclination direction and inclination angle of the measurement target surface WM with respect to the virtual reference plane (in this case, the surface of the table 2) (inclination direction and inclination of the inclination direction VT with respect to the virtual reference plane). The angle is determined, and the process is terminated.
In the above description, the inclination direction and the inclination angle of the measurement target surface WM, which is a part of the surface of the measurement object W, are obtained without obtaining the shape of the measurement object W, but as described below, If a large number of measurement points are set so as to scan the surface of the measurement object, the shape of the measurement object can be grasped.

● [Example of grasping the shape of the measurement object by scanning the surface of the measurement object (Fig. 4)]
For example, the control means 40 controls the displacement means 11 to move the position of the laser spot hit by the laser light from the laser measurement means 12 in a predetermined direction (X-axis direction, Y-axis direction, etc.) by a predetermined minute amount, and thereby the laser. The measurement is repeated and the surface of the measurement object is scanned. In this case, the control means 40 sets three or more measurement points so as to scan the surface of the measurement object (the operator may input three or more measurement points).
And the control means 40 calculates | requires each measurement distance Ln with respect to each measurement point WPn.
The example of the image data shown in FIG. 4 (A) shows an example in which the laser spot of each measurement point is displayed on the image of the measurement object in which two rectangular parallelepipeds are partially overlapped. Is shown.
In this way, if the number of measurement points on the surface of the measurement object is increased, not only the inclination direction and inclination angle of the surface to be measured, but also the shape of the object to be measured including a surface other than the surface to be measured is grasped. You can also

4B shows an example in which only measurement points are extracted from the image data shown in FIG. 4A and each measurement point is expressed by a circle (or polygon) having a predetermined diameter. Yes.
Further, the luminance (or density) of each circle (or each polygon) is expressed darker (or darker) as the measured distance corresponding to each measurement point or the distance based on the measured distance becomes longer.
The actually measured distance is the distance from the laser measuring means 12 to the measurement point, but the distance based on the actually measured distance is, for example, the distance from the tip of the imaging means 22 on the optical axis 22Z to each measurement point. This is the distance converted from the measured distance.
Then, the operator can change the shape of the measurement object by looking at the surface of the measurement object displayed on the display means of the control means and expressed in the light (darkness) of a circle (or polygon) of a predetermined diameter. Can be grasped sensuously.

As described above, the laser measurement system 1 described in the present embodiment can realize the measurement of the posture (tilt direction, tilt angle) of the measurement object with a simpler configuration and at a smaller size and lower cost. . For example, when the posture (inclination direction, inclination angle) of the measurement object is known, an accurate operation can be performed in a later process.
In addition, if the number of measurement points is increased so as to scan the surface of the measurement object, the shape of the measurement object can be measured.
Then, the scanned measurement points are represented by a circle (or polygon), and the luminance (or density) of the circle (or polygon) is changed and displayed according to the measured distance (or distance based on the measured distance). Thus, it is possible to display an image that allows the shape of the measurement object to be easily grasped.

The laser measurement system 1 of the present invention is not limited to the configuration, structure, shape, processing procedure, and the like described in the present embodiment, and various modifications, additions, and deletions can be made without changing the gist of the present invention. .
In the description of the present embodiment, as the displacement means 11, the example of the turning means 11A is shown in FIG. 2 (A) and the example of the moving means 11B is shown in FIG. 2 (B). You may have both means 11B. That is, the displacement means 11 only needs to have at least one of the turning means 11A and the moving means 11B.
In the description of the present embodiment, the surface of the table 2 is a virtual reference plane. However, the virtual reference plane can be set virtually on any plane, and the tilt direction and tilt with respect to the virtual reference plane can be set. The angle can be determined.

DESCRIPTION OF SYMBOLS 1 Laser measuring system 2 Table 10 Laser measuring apparatus 11, 11A, 11B Displacement means 12 Laser measuring means 20 Imaging apparatus 22 Imaging means 22Z Optical axis 40 Control means W Measurement object WM Measurement surface WP1-WP3 Measurement point

Claims (3)

Laser measuring means capable of measuring the distance to the laser spot where the irradiated laser light hits the surface to be measured by irradiating the surface to be measured of the object to be measured, and from the laser measuring means to the object to be measured A laser measuring device having: at least one of swiveling means capable of changing the direction and angle toward the surface or moving means capable of moving the position of the laser measuring means relative to the surface to be measured;
An imaging device that outputs image data of a two-dimensional image obtained by imaging at least the measurement target surface of the measurement object;
Control means for capturing image data from the imaging device and controlling the laser measurement means and the displacement means;
The approximate shape of the measurement object and the approximate shape of the surface to be measured are recognized in advance by the control means,
On the surface to be measured, at least three measurement points are set so as to form a polygon,
The measurement point is set by the control means, or is set by input from a user,
The control means includes
Recognizing the measurement surface of the measurement object based on image data from the imaging device;
The displacement means is controlled so that the set measurement point is irradiated with laser light, and the laser measurement light is irradiated from the laser measurement means to measure the measured distance that is the distance from the laser measurement means to the measurement point. Is performed for each of the measurement points,
Based on each of the measurement points and the measured distance, the inclination direction and the inclination angle of the measurement target surface with respect to a preset virtual reference surface are obtained.
Laser measurement system. The laser measurement system according to claim 1,
A display means,
Three or more measurement points are set on the surface of the measurement object so as to scan the surface of the measurement object,
The control means includes
Measure the measured distance from the laser measurement means to each measurement point,
Each measurement point is represented by a circle or polygon with a predetermined diameter and displayed on the display means.
The brightness or density of each circle or each polygon corresponding to each measurement point is displayed on the display means with the brightness becoming darker or darker as the distance based on the measured distance or the measured distance is longer.
Laser measurement system. The laser measurement system according to claim 1 or 2,
The control means includes
Based on the image data from the imaging device, the displacement means is controlled so that the set position of the measurement point and the position of the laser spot of the laser beam irradiated on the actual surface to be measured coincide with each other. To
Laser measurement system.

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