JPH10300439A - Laser cross section measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To set a measuring head in an optimum attitude relative to a subject for measurement. SOLUTION: A laser cross-section measuring device has, on plural portions of a measuring head 10, distance sensors 20A-20D provided at intervals to one another for recognizing the attitude of the measuring head 10 relative to work (example of subject for measurement) W, the measuring head 10 enclosing both a slit laser beam source 15, which applies a laser slit beam LS to the work W, and a camera 25 on which the laser slit reflected beam RLS from the work W impinges.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser cross-section measuring apparatus capable of irradiating a measuring object with a laser beam and measuring its cross-sectional shape in a non-contact manner.

[0002]

2. Description of the Related Art In a laser section measuring apparatus, a measuring head containing a slit laser light source for irradiating a laser beam to a measuring object such as a work and a camera for entering a laser slit reflected light from the measuring object is housed. Since the measuring head is not in contact with the measuring object, the direction of the measuring head with respect to the measuring object can be freely determined. In the measuring head, the position is adjusted by projecting an image on a screen display device such as a monitor so that it is difficult to know which position and how to measure.

[0003]

However, in the conventional laser section measuring apparatus, it is very difficult to exactly determine the parallelism between the workpiece and the measuring head only by viewing the image on a screen display device such as a monitor. In addition, since measurement cannot be performed without a screen display device, the configuration of the device is complicated and the price is high.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and it has been proposed to optimize the distance and angle of a measuring head with respect to a measuring object without displaying an image on a screen display device such as a monitor. It is an object of the present invention to provide a laser section measurement device that can be set.

[0005]

The present invention for achieving the above object is constituted as follows. The invention according to claim 1 is characterized in that, at a plurality of positions of a measurement head in which a slit laser light source that irradiates a laser slit light to a measurement target and a camera that receives laser slit reflected light from the measurement target are accommodated, A laser cross-section measuring device provided with a distance measuring sensor for recognizing a posture of the measuring head with respect to an object to be measured.

When the distance measuring sensors are provided at a plurality of positions on the measuring head, it is possible to recognize the posture of the measuring head with respect to the object to be measured.

According to a second aspect of the present invention, there is provided a slit laser light source for irradiating a laser slit light to an object to be measured, a camera for irradiating laser slit reflected light from the object to be measured, and a plurality of cameras arranged at a plurality of distances. Attitude display for calculating and displaying the attitude of the measurement head with respect to the measurement target based on the distance to the measurement target detected by each of the measurement heads containing the measured distance measurement sensors and the respective distance measurement sensors. Means for measuring a laser cross section.

When the distance measuring sensors are provided at a plurality of positions of the measuring head and the posture display means is provided, it is possible to know the posture of the measuring head with respect to the object to be measured. In other words, whether or not the laser slit light emitted from the slit laser light source is perpendicular to the object to be measured can be recognized while performing the operation, and accurate measurement can be performed on site.
The posture display means can clearly display the distance and angle between the work and the measuring head by numerical values. In addition, even when the robot is mounted on a robot or the like and automated, data on the distance and angle between the workpiece and the sensor can be obtained, so that it is easy to automate.

According to a third aspect of the present invention, there is provided a slit laser light source for irradiating a laser slit light to an object to be measured, a camera for irradiating laser slit reflected light from the object to be measured, and a plurality of cameras arranged at a plurality of distances. A measuring head in which the measured distance sensor is accommodated, and an image pickup signal from the camera is input to calculate the cross-sectional shape of the measured object, and the distance to the measured object detected by each of the measured distance sensors is calculated. Control means for recognizing the posture of the measurement head with respect to the measurement target based on the distance, and correcting the calculated cross-sectional shape based on the recognized posture to display an accurate cross-sectional shape of the measurement target. And a laser cross-section measuring apparatus characterized by having:

With this configuration, in addition to the operation of the second aspect of the present invention, the calculated cross-sectional shape without taking the ideal posture is based on the posture of the measuring head captured at the time of the measurement. Can be corrected,
With this correction, it becomes possible to obtain a cross-sectional shape when the laser slit light emitted from the slit laser light source is perpendicular to the object to be measured.

According to a fourth aspect of the present invention, in the laser section measuring apparatus according to any one of the first to third aspects, the distance measuring sensor outputs a point laser beam to connect the object to be measured with the distance measuring sensor. The distance is to be measured.

According to a fifth aspect of the present invention, in the laser section measuring apparatus according to any one of the first to third aspects, at least three or more distance measuring sensors are provided at arbitrary positions on the measuring head at a distance from each other. It is a thing.

[0013]

According to the first aspect of the present invention, it is possible to know the attitude of the measuring head with respect to the measuring object, so that the distance and angle of the measuring head with respect to the measuring object can be optimized. Can be set strictly parallel, for example.

According to the invention described in claim 2, according to claim 1,
In addition to the effects of the invention described in (1), it is possible to recognize whether or not the laser slit light is vertically applied to the object to be measured while performing on-site work, and it is possible to perform accurate on-site measurement. Therefore, it is not necessary to stop the work at the site every time.
Since the angle can be set optimally, on-site work can be performed continuously and efficiently.

According to the invention described in claim 3, according to claim 2
In addition to the effects of the invention described in (1), since the cross-section can be accurately measured even when the measuring head does not take an ideal posture with respect to the measurement target, the distance and angle of the measurement head with respect to the measurement target are strictly set. There is no need to do so, and the labor for the setting can be reduced.

According to the invention described in claim 4, according to claim 1 of the present invention,
In addition to the effects of the third aspect of the present invention, since the point laser beam hits only a narrow point of the object to be measured and does not spread, the error is reduced and the distance measurement becomes accurate.

According to the invention described in claim 5, according to claim 1,
In addition to the effects of the invention described in claim 3, the distance measuring sensor is provided at three or more locations on the measuring head, so
The distance to the point or more can be known, and the reference plane to be measured can be accurately recognized.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a laser section measuring apparatus according to the present invention will be described with reference to the drawings. As shown in FIG. 1, a laser cross-section measuring apparatus according to this embodiment includes a slit laser light source 15 that irradiates a work (an example of an object to be measured) W with laser slit light LS and a laser slit reflected light RLS from the work W. Distance measuring sensors (A to D) for recognizing the attitude of the measuring head 10 with respect to the work W at a plurality of positions on the measuring head 10 in which the camera 25 that receives the light is incident.
20A to 20D are provided.

Further, the cross-section measuring device is provided with the camera 2
And a control device 30 for calculating the cross-sectional shape of the work W by inputting the imaging signal from the control device 5.
A / D converter 32 which receives an analog video signal (imaging signal) from the camera 25, converts the analog video signal from analog to digital (A / D), and outputs a digital video signal; An image memory 34 for storing a captured image from a digital video signal, and calculating a cross-sectional shape of the work W from the stored digital video image, and calculating a distance to the work W detected by each of the distance measuring sensors 20A to 20D. An arithmetic processing unit 36 for calculating the attitude of the measuring head 10 with respect to the workpiece W (distance / angle to the workpiece, etc.) based on the workpiece W; and a measurement result output unit 38 for displaying the calculated attitude of the measuring head 10 and outputting the cross-sectional shape. And

Here, the arithmetic processing section 36 calculates and recognizes the attitude of the measuring head 10 with respect to the work W based on the distance to the work W detected by each of the distance measuring sensors 20A to 20D. Then, a correction based on the recognized posture is added to the calculated cross-sectional shape, and the accurate cross-sectional shape of the work W is displayed on the measurement result output unit 38.

The distance measuring sensors 20A to 20D
Preferably outputs a visible point laser beam to measure the distance between the workpiece W and the distance measuring sensors 20A to 20D. One is provided. In the embodiment, the measurement width of the distance measuring sensors 20A to 20D is set to be a measurement range WL determined by the irradiation angle of the slit laser light source 15 and the scanning field of view of the camera 25.

Next, the measurement procedure of the cross-section measuring apparatus of the embodiment will be described with reference to the flowchart of FIG. in this case,
The measurement state is as shown in FIG.
Has a step t. FIG. 3 also shows the X, Y, and Z directions. Distance sensor 20A, 20
The measurement distances of C, 20B and 20D are La and L, respectively.
b, Lc, and Ld.

First, in order to enable accurate distance measurement, the longest and shortest measurement distances L1 and L2 of the distance measurement sensors 20A to 20D are registered (step S1), and the measurement range WL is registered. (Step S2). Next, the reference surface step t of the work W is registered (step S3). Then, the type of the work to be measured (whether the work is concave or convex) is registered (step S4). The registration of these steps S1 to S4 is input to the control device 30 by any input means.

Next, the distance of the work W is measured using the point laser light of the distance measuring sensors 20A to 20D, and the work is put in the visual field of the measuring head 10 in the X direction (step S5). Then, the measuring head 10 is moved closer to the work W without moving in the X direction (moving only in the Y and Z directions) (step S6).

Next, when the workpiece W is a convex one such as a bead, it is determined whether or not the condition of La = Lb <L1, Lc = <L1 (L1 + t when there is a step) is satisfied. When W is concave, La =
Lb <L1, Lc = <L1 (L1-t when there is a step)
It is determined whether or not the condition is satisfied, and when the condition is satisfied, the automatic measurement is performed by the measuring head 10 (step S7).

Next, the section data measured by the measuring head 10 and the distance data La, Lb, Lc, Ld measured by the distance measuring sensors 20A to 20D are stored in the image memory 34 (step S8).

Then, it is determined whether or not the above-described cross-sectional data is output in parallel with the reference plane of the work W (step S).
9). If data in a state parallel to the reference plane is output (step S9: YES), the inclination angle θ of the measurement head 10 is calculated by the following equation (1) (step S10).

Θ = tan ⁻¹ (La−Lc) / w (1) Next, all the point sequence data is rotationally converted at the inclination angle θ using the following equation (2) (step S 11).

[0029]

(Equation 1)

By the above processing, the same data as in the state where the measuring head 10 is set parallel to the measuring surface of the workpiece W is calculated.

Then, the cross-section data thus converted is output from the measurement result output unit 38 (step S1).
2).

On the other hand, if the reference plane does not need to be output in parallel in step S9 (S9: NO), the measured data may be output as it is, so that the above-described rotation conversion calculation is not performed, and The data is output to the measurement result output unit 38.

FIG. 4 shows an application example in which the laser section measuring apparatus according to the present invention is attached to a robot hand and actually used on site, and the measurement is performed by attaching the measuring head 10 to the attachment 40. The form is shown.

As shown in FIG. 4A, first, a reference block 45 whose X-direction distance A to the vertex and Y-direction height B are known is measured and initialized. And FIG.
As shown in (B), the cross-sectional shape of a panel as an example of the work W is measured. In this case, the measuring head 10 is moved in the Y and Z directions without moving in the X direction, and the slit light is adjusted to the scribe line drawn in the Z direction perpendicular to the paper surface.

The cross-sectional data measured in this manner is appropriately rotated and converted to obtain the cross-sectional shape of the work.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a measuring head and a control device of a laser cross-section measuring device according to the present invention.

FIG. 2 is an operation flowchart of the apparatus shown in FIG. 1;

FIG. 3 is a diagram provided for explanation of the operation of the operation flowchart of FIG. 2;

4A and 4B are diagrams showing an application example of the laser cross-sectional shape measuring apparatus according to the present invention, wherein FIG. 4A shows initialization by reference block measurement, and FIG. 4B shows work measurement.

[Explanation of symbols]

 Reference numeral 10: measuring head, 15: slit laser light source, 20A to 20D: distance measuring sensor, 25: CCD camera, 30: control device, W: work.

Claims (5)

[Claims] 1. A measuring head (1) in which a slit laser light source (15) for irradiating a laser slit light to a measuring object (W) and a camera (25) for irradiating laser slit reflected light from the measuring object are housed. 10) A laser cross-section measuring apparatus, wherein distance measurement sensors (20A to 20D) for recognizing the attitude of the measurement head with respect to the measurement object are provided at a plurality of locations. 2. A slit laser light source (15) for irradiating a measuring object (W) with laser slit light, a camera (25) for irradiating a laser slit reflected light from the measuring object (W), and a plurality of positions at a distance from each other. Calculating and displaying the attitude of the measurement head with respect to the measurement target based on the distance to the measurement target detected by each of the distance measurement sensors and the measurement head disposed therein. Posture display means (3
0). 3. A slit laser light source (15) for irradiating the object to be measured (W) with laser slit light, a camera (25) for receiving a laser slit reflected light from the object to be measured, and a plurality of positions spaced apart from each other. A measuring head in which a distance measuring sensor arranged therein is accommodated, and an imaging signal from the camera is input to calculate a cross-sectional shape of the measuring object, and the measuring object detected by each of the distance measuring sensors Recognize the attitude of the measurement head with respect to the measurement target based on the distance to the object, and correct the calculated cross-sectional shape based on the recognized attitude to display the accurate cross-sectional shape of the measurement target. A laser section measurement device, comprising: a control unit (30). 4. The distance measuring sensor according to claim 1, wherein the distance measuring sensor outputs a point laser beam to measure a distance between the object to be measured and the distance measuring sensor. The laser cross-section measurement device according to item 1. 5. The measurement sensor according to claim 1, wherein at least three of the distance measurement sensors are provided at arbitrary positions on the measurement head at a distance from each other.
The laser cross-section measuring device according to any one of the above.