JPH0694637A - Flash detecting equipment for industrial robot and flash grinding route generating equipment therefor - Google Patents

Abstract

PURPOSE:To detect three-dimensionally the position and the shape of a flash in relation to the direction of formation thereof, using a base material surface of a workpiece whereon the flash is formed, as a reference, and being based on the positional relationship between the base material surface and the flash, without using a standard image for comparison, in detection of the flash. CONSTITUTION:A projector 7 applying a slit light 9 to a workpiece 1 having a flash 4 and an image pickup device 8 picking up an image of a part 12 irradiated by the slit light are provided. Moreover, an image memory 15 receiving and storing a light-section image 14 which is outputted from the image pickup device and contains a light image 14a corresponding to the part of the flash and a light image 14b corresponding to the part of a base material surface, a flash position computing means 17 which calculates a point A showing the position of the flash on the basis of the light image 14b, and an apex position computing means 18 which calculates a point showing the apex of the flash on the basis of the light image 14a, are provided. Besides, a height computing means 19 for calculating the height of the flash by using the coordinates of the point showing the position of the flash and the coordinates of the point showing the apex of the flash, a direction computing means 20 for calculating the direction of formation of the flash by using the aforesaid coordinates, and a conversion means 21 for determining the actual height and direction of formation of the flash by conversion of the height and direction of formation of the flash calculated above, are provided in the construction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a burr detection device and a burr grinding path generation device for an industrial robot, and more particularly, to automatically detect the formation state of a burr formed on a work and remove the burr from the work. The present invention relates to a deburring device for an industrial robot, which is useful for automating a deburring operation, and a deburring route generating device configured using this deburring device.

[0002]

2. Description of the Related Art In order to realize an industrial robot that automatically removes burrs from a workpiece formed during manufacturing and finishes the workpiece, the state of burrs formed on the workpiece is detected and the burrs are removed. It is required to determine a grinding path to be removed and control the grinding operation of the robot based on this grinding path. For example, when the work is a casting, burrs on the work are formed corresponding to the mold dividing surfaces. However, since the burr formation state, that is, its shape and formation position, differs for each work and cannot be determined as a common formation state, it is necessary to detect the burr formation state for each work in order to automate the deburring work. .

To give an example of the prior art for detecting burrs,
JP 62-113005 A, JP 63-229
The techniques disclosed in JP-A No. 317 and JP-A No. 1-152580 can be mentioned.

In Japanese Unexamined Patent Publication No. 62-113005, slit light emitted from a laser light generator is applied to a corner portion of a work, and a light-section image formed by this and a pre-teached corner-free corner are present. Compare the standard light section image of the section. In this comparison, arithmetic processing is performed to calculate the offset amount, and the position and shape of the burr are detected based on the offset amount. With this technology, the position of the burr cannot be accurately detected when there is an installation error with respect to the work position, and it is difficult to teach the standard optical cutting image when the base material shape around the burr is complicated. Have.

In Japanese Unexamined Patent Publication No. 63-229317, an illuminating device for irradiating an object to be inspected with light, an image pickup device for picking up an image formed by the light irradiation, and a video signal output from the image pickup device are subjected to data processing. A technique is disclosed in which image data of an object to be inspected is created by using a calculation unit and a burr portion is detected as a shadow. Further, in JP-A-1-152580, the position and shape of the burr are detected by taking the difference between the image of the part having a burr which is the inspection object and the image of the part having the basic shape which is taught and having no burr. A method is disclosed. In these techniques, since the image of the inspection object is created using the principle of plane projection, there is a problem that the vertical position of the burr, that is, the burr cannot be three-dimensionally detected.

[0006]

According to the recent tendency of the conventional burr detection technique, a standard image which does not have a burr which has been taught in advance is prepared in an image memory based on an image processing technique, and a work image having a burr exists. In general, it is created, the standard image and the work image are compared, and the position and shape are detected based on the burr image as the difference.

However, it is difficult or difficult to create a standard image as a reference for comparison, depending on the location where burrs are formed on the work and the complexity of the shape of the work to be inspected. It can be completely impossible. Therefore, there is a problem that it can be applied only in a considerably limited range. Also, the burr image obtained as a difference by comparison is a planar (two-dimensional)
Since it is an image, there is a problem that information such as the vertical position of the burr cannot be obtained from the data related to the image. This raises the problem that unless the information on the vertical position of the burr can be accurately obtained, the grinding path for sufficiently removing the burr cannot be accurately determined.

An object of the present invention is to determine the position in the direction of burr formation based on the positional relationship between the base material surface and the burr with reference to the base material surface of the work on which the burr is formed, without using a standard image for comparison. Another object of the present invention is to provide a burr detection device for an industrial robot capable of stereoscopically detecting a shape, and to provide a burr grinding path generation device for an industrial robot configured using this burr detection device.

[0009]

A burr detection device for an industrial robot according to the present invention comprises a projector for irradiating an object having burrs with slit light, and an image pickup device for picking up an image of a portion irradiated with slit light. , Having a configuration having an image memory for inputting and storing a light section image output from the imaging device,
The light-section image includes a light image corresponding to the burr portion and a light image corresponding to the base material surface portion, and a point representing a burr position based on the light image corresponding to the base material surface portion. A burr position calculation means, a vertex position calculation means for calculating a point representing a burr vertex based on an optical image corresponding to the burr portion, and coordinates of a point representing a burr position and a point representing the burr vertex. Height calculation means for calculating the height of the burr using the coordinates, direction calculation means for calculating the burr forming direction using the coordinates of the point representing the burr position and the coordinates of the point representing the burr apex, and And a conversion unit for converting the height and the forming direction of the formed burr to obtain the actual height and the forming direction of the burr. In the above structure, preferably, the base material surface is formed so as to intersect at a certain angle on both sides of the burr, and the number of optical images corresponding to the base material surface portion is two. A burr grinding path generation device for an industrial robot according to the present invention includes a projector that irradiates an object having burrs with slit light, an imaging device that images a portion irradiated with slit light, and light provided from the imaging device. It has a structure having an image memory for storing a cut image, and the light cut image includes a light image corresponding to the burr portion and a light image corresponding to the base material surface portion, and corresponds to the base material surface portion. The burr position calculation means for calculating a point representing the burr position based on the optical image, the apex position calculation means for calculating a point representing the apex of the burr based on the optical image corresponding to the burr part, and the burr position A height calculation means for calculating the height of the burr by using the coordinates of the point and the coordinates of the points representing the burr vertices, and the burr using the coordinates of the point representing the burr position and the coordinates of the point representing the burr vertex. Calculation means for calculating the forming direction of the Converting means for converting the height and forming direction of the formed burr to obtain the actual height and forming direction of the burr, and the height and forming of the burr at a plurality of points from the start point to the end point of the portion where the burr is formed. And a grinding path generation means for generating a grinding path for the burr by using the data of the burr height and the formation direction which are finally obtained by the output of the conversion means for the entire burr.

[0010]

In the present invention, the visual sensor consisting of the slit light projector and the television camera is used to irradiate the slit light to the peripheral portion of the burr whose position and shape are to be detected. The television camera takes an image of an irradiation line drawn as a straight line on the work surface based on the slit light, and stores it in the image memory as a light section image. Using the two light images corresponding to the base material surface portion and the light image corresponding to the burr portion included in the light section image stored in the image memory, the position and height of the burr and the formation direction (shape) Ask for. In order to obtain the position of the burr, it is desirable that the base material surfaces on both sides of the burr be flat and intersect at a certain angle. Furthermore, the data on the burr occurrence position, the burr height and the forming direction (vector) obtained by using the burr position detection are supplied to the robot controller of the grinding robot, and based on a series of burr occurrence position data. The robot controller generates a grinding path for the burr to be ground. The robot controller has a burr grinding path generating means.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a perspective view conceptually showing the principle of burr detection according to the present invention. In FIG. 1, reference numeral 1 denotes a work which is an object to be inspected, and the work 1 is supported by two support bases 2 and 3. The work 1 is, for example, a casting, and 2
It is formed using one mold. 4 in the work 1 indicates a burr. The burr 4 is a casting burr formed corresponding to the dividing surfaces of the two molds. Flat base material surfaces 5 and 6 are formed on both sides of the burr 4. As shown in FIG. 2, the base material surfaces 5 and 6 on both sides have a constant angle θ1 at the burr forming portion.
Are in a positional relationship of intersecting so as to form.

The burr detection according to this embodiment utilizes a light section image. A slit light projector 7 that emits slit-shaped laser light toward the burr portion to create a light-section image;
A television camera 8 that receives reflected light of the slit-shaped laser light and picks up an image of the burr portion is arranged. The respective arrangement positions are set so that the axis line 10 of the laser beam 9 emitted from the light projector 7 and the axis line 11 in the imaging direction of the television camera 6 form a predetermined angle θ2, for example, 30 °. In the illustrated example, the projector 7 and the television camera 8 are arranged above the burr 4. As a light source of the projector 7, a semiconductor laser that is not easily affected by ambient light is desirable. On the other hand, it is desirable to attach an interference filter having a spectral sensitivity characteristic corresponding to the wavelength region of the semiconductor laser to the light receiving portion of the television camera 6. With regard to the mounting structure of the projector 7 and the television camera 8, a detailed description of the structure will be omitted.

The projector 7 is supplied with electric power from a power source (not shown) and irradiates the surface of the work 1 including the predetermined portion of the burr 4 with the slit-shaped laser light 9. Line 12 in FIG.
An irradiation line formed by the slit-shaped laser light 9 on the surface of the work 1 is shown. The irradiation line 12 is formed so as to be substantially orthogonal to the burr 4. The television camera 8 images the burr part where the irradiation line 12 is formed and the base material surface part around the burr part. A light section image can be obtained in the image signal 13 output from the television camera 8. In this way, the light projector 7 and the television camera 8 create a light-section image of an arbitrary burr portion and the surface of the base material around it. The light cut image of the burr is shown by the projector 7.
By simultaneously moving the unit of the TV camera 8 along the burr 4, a plurality of measurement points are created at predetermined intervals.

Image signal 1 output from the television camera 8
3 is image-processed by an image processing device (not shown), and the obtained light section image 14 is stored in the image memory 15. The light section image 14 is the light image 14 corresponding to the portion of the burr 4.
a and an optical image 14b corresponding to the base material surfaces 5 and 6 on both sides of the burr 4. Information on the shape corresponding to the contour of the burr 4 formed on the base material surface of the work 1 can be obtained from the light section image 14. In the image memory 15, XY coordinates are defined. Such a light section image 14 is the work 1
Is created corresponding to each measurement point of and is stored in the image memory 15.

Using the projector 7 and the TV camera 8, the flash 4
When the light section image 14 is obtained for an arbitrary portion of, the position and shape of the burr portion which is the imaging target can be obtained using the data of the light section image 14. By performing similar imaging and data processing on a plurality of locations on the burr 4, the position and shape of the entire burr 4 can be obtained.

An image of an arbitrary portion of the burr 4 is picked up, and the image memory 1
When the light section image 14 is stored in 5, the light section image 1 is stored.
4 is used to determine the position and shape (height and direction) of the burr at the imaging location. A method of obtaining the position, height, and direction of the burr at the imaged location based on the light section image 14 of the burr will be described with reference to FIGS. 3 and 4.

The light section image 14 stored in the image memory 15
Data is taken into the arithmetic unit 16. Arithmetic unit 16
Is constituted by, for example, a microcomputer, and each function means shown in FIG. 3 is realized by software by a program stored in the memory.

The burr position calculation means 17 of the calculation device 16 obtains the position of the burr 4. The position of the burr is the intersection A of the optical image 14b corresponding to the base material surfaces 5 and 6 as shown in FIG.
Is defined as In order to obtain the intersection point A, each of the two optical images 14b is expressed by a linear equation, the solution of the two linear equations is obtained, and the coordinates of the intersection point A are the burr occurrence position.

The vertex position computing means 18 of the computing device 16 finds the coordinates of the vertex B of the optical image 14a representing the shape corresponding to the contour of the burr, and sets the coordinates as the vertex position.

When the intersection point A and the vertex B are obtained, the height calculation means 19 calculates the height H of the burr using the coordinate data of the points A and B, and the direction calculation means 20 calculates the direction K of the burr.
Is calculated. The height H of the burr is calculated as the distance between the two points A and B. The burr direction K is obtained by expressing each of the points A and B as a vector based on a predetermined reference point and performing vector subtraction to determine the direction from the point A to the point B as the burr direction.

The burr 4 which is the image pickup target of the television camera 8.
After calculating the height H and the direction K of the position of the light section image 14 stored in the image memory 15 as described above,
The conversion means 21 calculates the actual height and direction of the casting burr 4. In this conversion, the tilt angle θ2 is used. In this way, the height and direction of the actual imaging portion of the burr 4 formed on the work 1 can be obtained. A plurality of image pickup locations in the burr 4 are set in advance, and the units of the projector 7 and the TV camera 8 are sequentially moved to the respective image pickup locations of the burr 4, and the position, height, and direction of each image pickup location are set in the same manner as described above. Ask. As a result, the formation position and shape of the entire burr 4 are detected.

Light section image 14 stored in image memory 15
Does not always occur as shown in FIG. As shown in FIG. 5, for example, when the formation direction of the burr 4 is largely inclined to one side, the light section image 14 may be partially cut off (the portion indicated by the broken line 14c). In this case, the intersection A representing the position of the burr 4 is obtained in the same manner as above. On the other hand, regarding the vertex B, since there is no point corresponding to the vertex in terms of shape, the end point at the highest position is treated as the vertex B. The method of calculating the height and direction of the burr after that is the same as that in the above embodiment.

FIG. 6 is a perspective view of a robot system for deburring work in which the deburring device according to the present invention is attached to a deburring robot. Grinding of the burr 4 on the work 1 which is a casting is performed by a grinding tool 24 attached to a wrist 23 of the robot 22. For burr grinding, it is necessary to generate the grinding path of the grinding tool 24 before the work. The burr position detecting device described above is used in the generation of the grinding path. The slit laser light projector 7 and the television camera 8 are attached to a support member 27 of a wrist 23 of the robot 22. In this mounted state, the projector 7 and the TV camera 8 face the work 1 placed on the work table 25,
The work 1 is irradiated with the laser beam 9 from the light projector 7. The floodlight 7 and the television camera 8 are based on the operation of the robot 22 and, according to the data of the detection path generated by the robot controller 26 in advance teaching, the burr 4 to be ground.
Move the position above. In this movement, when the teaching point on the detection route is reached, the television camera 8 performs an imaging operation to image the irradiation line 12. The light section image obtained by the television camera 8 is supplied to the image memory 15 and stored therein. The arithmetic unit 16 detects the position, height and direction of the flash portion imaged as described above by using the light section image stored in the image memory 15. These data are obtained for each teaching point from the start point to the end point of the detection route, and the position and shape data obtained for the burr 4 are
It is stored in the memory of the robot controller 26.

At the next stage, the robot controller 26 uses the detection data on the position and shape of the burr 4 to
A grinding path of the grinding tool 4 for grinding the burr 4 is generated. The robot controller 26 includes a burr grinding path generating means inside. Further, parameters necessary for the burr grinding, such as the grinding angle and the rotational speed of the grindstone, are automatically generated. A grinding operation for grinding and removing the burr 4 with the grinding tool 24 is executed based on data such as a grinding path prepared by the robot controller 26. Various data for executing the grinding work are sent from the robot controller 26 to a drive mechanism provided inside the robot 22.

In the above embodiment, the burrs to be detected were casting burrs formed by the dividing surfaces of the mold. This burr detection device can be similarly applied to, for example, a casting burr formed on a corner portion of a casting or a burr formed by machining or the like. The base material surface of the work formed on both sides of the burr is preferably a flat surface, but is not limited to this. As the visual sensor, a device having a similar function instead of the slit light projector and the television camera, for example, a one-dimensional CC
A D camera or PSD (Position Sensing Device) can be used.

[0026]

As is apparent from the above description, according to the present invention, a visual sensor composed of a slit light projector and a television camera is used for detecting the position and shape of a burr on a work, and the mother on both sides of the burr is used. Since the detection is performed using the material surface as a reference, a standard image for comparison is not required, there is no positional deviation, etc., the detection error is small, and it is possible to deal with works with complicated shapes. Have. Also, the burr occurrence state (position and shape)
Can be detected three-dimensionally, and burrs can be detected with high accuracy. Further, by attaching the burr position detecting device to the deburring work robot and providing the burr grinding path generating means, it is possible to automatically generate the grinding path of the grinding tool provided on the wrist of the robot.

[Brief description of drawings]

FIG. 1 is a perspective view for explaining the principle of burr detection of a burr detection device according to the present invention.

FIG. 2 is a partial vertical cross-sectional view of a work to be detected.

FIG. 3 is a block configuration diagram of a burr position detection device realized by a calculation device.

FIG. 4 is a front view showing a light section image stored in an image memory.

FIG. 5 is a diagram showing another example of a light section image.

FIG. 6 is a perspective view showing a burr grinding robot provided with a burr detection device according to the present invention.

[Explanation of symbols]

 1 ... Work 4 ... Burr 5, 6 ... Base material surface 7 ... Slit light projector 8 ... TV camera 9 ... Slit light 12 ... Irradiation line 13 ... Image signal 14 ... Light section image 15 ... Image memory 16 ... Computing device 22 ... Robot 26 ... Robot controller

[Procedure amendment]

[Submission date] December 18, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0022

[Correction method] Change

[Correction content]

Light section image 1 stored in image memory 15
4 does not always occur as shown in FIG. Figure 5
As shown in, for example, when the formation direction of the burr 4 is largely inclined to one side, it is partially (a portion indicated by a broken line 14c).
There is also a case where the light section image 14 is missing and is generated. in this case,
The intersection A representing the position of the burr 4 is obtained in the same manner as above. On the other hand, regarding the vertex B, since there is no point corresponding to the vertex in terms of shape, the end point at the highest position is treated as the vertex B. The method of calculating the height and direction of the burr after that is the same as that in the above embodiment. Still partially
As another example of the case where the missing light section image 14 is generated,
Two base metal surfaces intersect at an angle of 90 ° to form a corner
Burr occurs so as to form the same surface as one base metal surface
The case can be mentioned. In this case, the burr part
Light image corresponding to the minute and the light image corresponding to one base material surface part
Is a straight line that makes it difficult to distinguish these two optical images.
Form a light-cut image. That is, the left side portion in FIG.
The minute light image 14b is not a broken line as shown in FIG.
It becomes a straight line. Also, the optical image corresponding to the burr and the mother of the other
As described above, there is a gap between the light image and the material surface.
Parts occur.

Claims (3)

[Claims] 1. A light projector for irradiating an object having burrs with slit light, an image pickup device for picking up an image of a portion irradiated with slit light, and an image memory for storing a light section image given from the image pickup device. In the burr detection device for an industrial robot, the light-section image includes a light image corresponding to a burr portion and a light image corresponding to a base material surface portion, and the light image corresponding to the base material surface portion is A burr position calculation means for calculating a point representing a burr position based on the burr position, an apex position calculation means for calculating a point representing a burr apex based on the optical image corresponding to the burr portion, and a point representing the burr position Height calculation means for calculating the height of the burr by using the coordinates of the point and the coordinates of the point representing the apex of the burr, and the coordinates of the point representing the position of the burr and the coordinates of the point representing the apex of the burr How to calculate the burr formation direction Computing means and, burr detecting device of an industrial robot in which the conversion means for obtaining the height and forming direction of the actual burr by converting the height and the formation direction of the calculated burr, characterized in that it comprises for. 2. The burr detection device for an industrial robot according to claim 1, wherein the base material surface is formed so as to intersect at a certain angle on both sides of the burr, and the light corresponding to the base material surface portion is formed. A burr detection device for an industrial robot, which has two images. 3. A light projector for irradiating an object having burrs with slit light, an image pickup device for picking up an image of a portion irradiated with slit light, and an image memory for storing a light section image given from the image pickup device. In an industrial robot, the light-section image includes a light image corresponding to a burr portion and a light image corresponding to a base material surface portion, and a burr image based on the light image corresponding to the base material surface portion is formed. A burr position calculation means for calculating a point representing a position, a vertex position calculation means for calculating a point representing a vertex of the burr on the basis of the optical image corresponding to the burr portion, and coordinates of the point representing the burr position and a burr Height calculating means for calculating the height of the burr by using the coordinates of the point representing the apex of the burr, and the burr forming direction using the coordinates of the point representing the burr position and the coordinates of the point representing the burr apex Direction calculation means for calculating Conversion means for calculating the actual height and forming direction of the burr by converting the calculated height of the burr and the forming direction, and the burr at a plurality of points while the portion where the burr is formed is reached from the start point to the end point. The height and the forming direction of the burr, and the grinding path generation means for generating the grinding path of the burr by using the data of the height and the forming direction of the burr finally obtained by the output of the conversion means for the entire burr, A burr grinding path generation device for an industrial robot, comprising: