JPH07227784A - Method and device for matching coordinates between vision device and industrial robot - Google Patents

Abstract

PURPOSE:To improve accuracy for matching coordinates between a robot coordinate system and a vision coordinate system. CONSTITUTION:In a state where positions are determined on three points, the coordinate values of a hand part 2b on a 180 deg. rotation symmetrical position are obtained by self rotating any the wrist shaft of an industrial robot 2, the coordinate values of the wrist rotary shaft on a vision coordinate system are obtained based on both coordinate values and a coordinate transformation matrix is obtained based on coordinate values on a robot coordinate system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for aligning a coordinate between a vision device and an industrial robot and the device therefor. More specifically, the hand portion of the industrial robot is positioned within the field of view of the vision device, The present invention relates to a method for obtaining coordinate values of a robot with a vision device and performing coordinate alignment between the vision device and an industrial robot and the device.

[0002]

2. Description of the Related Art Conventionally, in a system for handling an object to be processed using an industrial robot, the area to be handled is included in the visual field of a vision device, and the coordinate value of the object to be processed (vision The coordinate value in the coordinate system, hereinafter referred to as the vision coordinate value) is obtained, and the vision coordinate value is converted into the coordinate value in the coordinate system of the industrial robot (hereinafter referred to as the robot coordinate value) based on a predetermined conversion matrix. The operation command is given to the industrial robot. Therefore, in the industrial robot, the object to be processed can be gripped by operating each axis based on the operation command given from the vision device.

As is clear from the above description, in order to operate the system without any inconvenience, it is necessary to obtain a predetermined conversion matrix in advance, that is, coordinate adjustment between the vision device and the industrial robot. is there. As a method of aligning the coordinates between the vision device and the industrial robot in this way, conventionally, the hand portion of the industrial robot is sequentially positioned at three different points within the field of view of the vision device (these three points The robot coordinate values are obtained according to the conditions for positioning), and the vision coordinate values of the hand unit at each of these points (specifically, for example, the vision coordinate values at a predetermined position of the hand unit) are obtained, and the robot is divided into three points. A method of obtaining a transformation matrix based on coordinate values and vision coordinate values has been adopted. That is, if this method is adopted, the plane supporting the object to be processed is uniquely determined by three arbitrary points within the field of view of the vision device, so that the entire range of the plane supporting the object to be processed is determined by the vision device and the industrial equipment. It seems that it is possible to achieve a coordinate alignment with the application robot.

[0004]

However, in reality, since there is a deviation due to a dimensional error or the like between the rotation center of the wrist axis of the industrial robot and the predetermined position of the hand portion, Even if the transformation matrix is obtained by the above-mentioned conventional method, when the transformation coordinate matrix is used to calculate the robot coordinate value from the vision coordinate value, it deviates from the actual robot coordinate value. Further, since it is almost impossible to grasp this shift amount, it is only known that the object to be processed is present in a predetermined area centered on the converted robot coordinate value, and it is quite possible. It is not possible to obtain an accurate position and orientation (angle with respect to the reference axis).

In order to eliminate such inconvenience, it is conceivable to improve the dimensional accuracy, the assembly accuracy, etc. of the industrial robot itself so that the hand part and the rotation center of the wrist shaft coincide with each other, but there is no deviation between them. Is almost impossible to
Considering that the hand part is rotated about the center of rotation of the wrist shaft, as shown in FIG. 7, a deflection around twice the above deviation occurs.

Further, a jig for position detection is provided in a state where the hand portion is offset, and the wrist shaft is rotated by 180 °.
It is conceivable to adopt a method of detecting the position of the jig with the vision device in the rotated state and calculating the center position of both detection positions to accurately calculate the rotation center position of the wrist axis. It is difficult to make the deviation from the hand part sufficiently small, and as a result, a certain amount of deflection occurs. Therefore, when it is required to position the object to be processed with a deflection that is smaller than this deflection (highly accurately), a separate positioning device must be provided.

Further, for example, when the coordinates of the industrial robot are distorted non-linearly, even if a transformation matrix is obtained based on the coordinate values of the three points in the visual field of the vision device, the positions apart from the above three points will be obtained. In, the accuracy of the coordinate values after conversion will be reduced. As a result, it is possible to obtain highly accurate robot coordinate values in the vicinity of the above three points.
If the distance is far from the point, only the robot coordinate value including a relatively large error may be obtained.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides a vision device and an industrial robot capable of accurately achieving coordinate conversion between a vision coordinate system and a robot coordinate system. A first object of the present invention is to provide a coordinate adjusting method and an apparatus therefor, which can achieve a coordinate conversion between a vision coordinate system and a robot coordinate system almost accurately over almost the entire visual field of the vision device. A second object of the present invention is to provide a method and a device for aligning the coordinates between the robot and the industrial robot.

[0009]

According to a first aspect of the present invention, there is provided a coordinate system for aligning a vision device with an industrial robot, wherein a hand portion of the industrial robot is positioned within a visual field of the vision device. , A method of obtaining coordinate values of a hand unit by a vision device and performing coordinate adjustment between the vision device and an industrial robot, wherein the hand unit of the industrial robot is set to at least three different points in the visual field of the vision device. Sequentially position and rotate the wrist axis of the industrial robot in the state where the hand part is located at each point, and obtain the coordinate values of the hand part at multiple rotation positions with the vision device. Based on the coordinate values of the wrist rotation axis based on the
It is a method of obtaining a matrix for coordinate conversion between the coordinate system of the industrial robot and the coordinate system of the vision device based on the obtained coordinate values and the coordinate value of the industrial robot.

According to a second aspect of the present invention, there is provided a method of aligning a coordinate between a vision device and an industrial robot, wherein only the wrist axis of the industrial robot is rotated 180 ° in a state where the hand portion is positioned at each point and the hand is positioned at two rotational positions. This is a method in which the coordinate values of the parts are obtained by a vision device and the coordinate values of the wrist rotation axis are obtained based on the two obtained coordinate values. In the coordinate alignment method between the vision device and the industrial robot according to claim 3, the number of points for sequentially positioning the hand parts of the industrial robot at different points in the field of view of the vision device is 4, and the wrist rotation axis at 3 points. On the basis of the obtained coordinate value and the coordinate value by the industrial robot, obtain a matrix for coordinate conversion between the coordinate system of the industrial robot and the coordinate system of the vision device, and obtain another one point. This is a method of performing coordinate conversion based on the obtained matrix to obtain a coordinate conversion error, and correcting the matrix so that the coordinate value is translated in a direction in which the error decreases by 1/2 of the coordinate conversion error.

According to a fourth aspect of the present invention, there is provided a method for aligning a coordinate between a vision device and an industrial robot, wherein the hand part of the industrial robot is previously provided with an auxiliary tool having a predetermined shape to be recognized, and the hand part is positioned at each point. In this state, by rotating only the wrist axis of the industrial robot, the coordinate value of the predetermined position of the recognition target shape of the assist tool at multiple rotation positions is obtained by the vision device, and the wrist rotation axis is obtained based on the obtained multiple coordinate values. Is a method of obtaining the coordinate values of.

According to a fifth aspect of the present invention, there is provided a coordinate system for aligning a vision device with an industrial robot, wherein the hand part of the industrial robot is positioned within the field of view of the vision device, and the coordinate value of the hand part is obtained by the vision device. An apparatus for performing coordinate alignment with an industrial robot, comprising: first positioning means for sequentially locating the hand portion of the industrial robot at at least three different points in the visual field of the vision device;
Second positioning means for rotating only the wrist axis of the industrial robot in a state where the hand part is positioned at each point by the positioning means, and the coordinate value of the hand part at a plurality of rotational positions positioned by the second positioning means First coordinate value acquisition means obtained by the device, second coordinate value acquisition means for obtaining coordinate values of the wrist rotation axis based on the plurality of coordinate values obtained by the first coordinate value acquisition means, and wrist rotation at at least three points A matrix for coordinate conversion between the coordinate system of the industrial robot and the coordinate system of the vision device based on the coordinate value of the axis obtained by the second coordinate value obtaining means and the coordinate value of the industrial robot. And a transformation matrix obtaining means for obtaining the transformation matrix.

According to a sixth aspect of the present invention, there is provided a coordinate system for aligning a vision device with an industrial robot, wherein as the second positioning means, only the wrist axis of the industrial robot is rotated by 180 ° with the hand portion positioned at each point. Is adopted. In the coordinate alignment device for a vision device and an industrial robot according to claim 7, the number of points for sequentially locating the hand parts of the industrial robot at mutually different points in the field of view of the vision device is 4, and as a conversion matrix acquisition means, Of the above four points,
Obtaining a matrix for coordinate conversion between the coordinate system of the industrial robot and the coordinate system of the vision device based on the obtained coordinate values of the wrist rotation axis at three points and the coordinate values of the industrial robot The coordinate conversion error obtaining means for obtaining the coordinate conversion error by performing the coordinate conversion on the basis of the obtained matrix, and the coordinate value in the direction in which the error is reduced by 1/2 of the coordinate conversion error. And a conversion matrix correction means for correcting the above matrix so as to translate the matrix.

In the coordinate system for the vision device and the industrial robot according to claim 8, an auxiliary tool having a predetermined shape to be recognized is provided in advance in the hand portion of the industrial robot, and the first coordinate value obtaining means is provided. In this case, the vision device obtains the coordinate value of the predetermined position of the recognition target shape of the auxiliary tool at the plurality of rotational positions positioned by the second positioning means.

[0015]

According to the coordinate alignment method of the vision device and the industrial robot of claim 1, the hand portion of the industrial robot is positioned within the field of view of the vision device, and the coordinate value of the hand portion is obtained by the vision device. A state in which the hand part of the industrial robot is sequentially positioned at at least three different points in the field of view of the vision device when the coordinates of the device and the industrial robot are aligned, and the hand part is positioned at each point. In the industrial robot, only the wrist axis is rotated to obtain the coordinate values of the hand portion at a plurality of rotational positions by the vision device, and the coordinate values of the wrist rotational axis are obtained based on the obtained plurality of coordinate values. Based on the obtained coordinate value and the coordinate value by the industrial robot of the wrist rotation axis in, the coordinate between the coordinate system of the industrial robot and the coordinate system of the vision device is Since the matrix for conversion is obtained, even if there is a deviation between the wrist rotation axis and the hand part, by obtaining the coordinate values of the wrist rotation axis based on the coordinate values at a plurality of rotation positions, The influence of the deviation can be eliminated, and highly accurate coordinate alignment can be achieved.

According to the method of aligning the coordinates between the vision device and the industrial robot of claim 2, only the wrist axis of the industrial robot is 180 ° when the hand portion is positioned at each point.
By rotating the vision device to obtain the coordinate values of the hand part at two rotational positions and by obtaining the coordinate values of the wrist rotation axis based on the obtained two coordinate values, the number of rotational positions can be minimized. In addition, the calculation process of the coordinate value of the wrist rotation axis can be simplified.

According to the coordinate alignment method of the vision device and the industrial robot of claim 3, the number of points for sequentially positioning the hand parts of the industrial robot at different points in the visual field of the vision device is 4, and 3 Of the wrist rotation axis at the point,
A matrix for coordinate conversion between the coordinate system of the industrial robot and the coordinate system of the vision device was obtained based on the obtained coordinate value and the coordinate value of the industrial robot, and another point was obtained. Coordinate conversion based on the matrix to get the coordinate conversion error,
Since the above matrix is corrected in order to move the coordinate values in parallel in the direction in which the error is reduced by 1/2 of the coordinate conversion error, when the coordinates of the industrial robot or the coordinates of the vision device are nonlinearly distorted, Although the coordinate alignment accuracy in the vicinity of the three points is slightly lowered, the coordinate alignment accuracy at the position distant from the above three points can be increased, and as a result, the variation in the coordinate alignment accuracy can be eliminated over the entire range of the visual field of the vision device. be able to.

According to the coordinate alignment method of the vision device and the industrial robot of claim 4, an auxiliary tool having a recognition target shape of a predetermined shape is previously provided in the hand portion of the industrial robot, and the hand portion is provided at each point. In the positioned state, only the wrist axis of the industrial robot is rotated to obtain the coordinate value of the predetermined position of the recognition target shape of the assist tool at a plurality of rotation positions by the vision device, and the wrist is based on the obtained plurality of coordinate values. Since the coordinate value of the rotation axis is obtained, the coordinate value of the wrist rotation axis can be obtained in the sub-pixel order, and the coordinate alignment accuracy can be further improved.

According to a fifth aspect of the present invention, in the coordinate alignment apparatus for a vision device and an industrial robot, the hand portion of the industrial robot is positioned within the field of view of the vision device, and the coordinate value of the hand portion is obtained by the vision device. In aligning the coordinates of the apparatus and the industrial robot, the first positioning means sequentially positions the hand portion of the industrial robot at at least three mutually different points in the visual field of the vision device, and the first positioning means. In the state where the hand portion is positioned at each point by the second positioning means, only the wrist axis of the industrial robot is rotated, and on the vision coordinate system of the hand portion at a plurality of rotational positions positioned by the second positioning means. The coordinate value of is obtained by the first coordinate value acquisition means. Then, based on the plurality of coordinate values obtained by the first coordinate value obtaining means, the second coordinate value obtaining means obtains coordinate values of the wrist rotation axis, and at least three second coordinate values of the wrist rotation axis. Based on the coordinate values obtained by the acquisition means and the coordinate values on the robot coordinate system by the industrial robot, the conversion matrix acquisition means performs coordinate conversion between the coordinate system of the industrial robot and the coordinate system of the vision device. You can get the matrix for That is, coordinate alignment can be achieved. Therefore, even if there is a deviation between the wrist rotation axis and the hand portion, it is possible to eliminate the influence of the deviation by obtaining the coordinate values of the wrist rotation axis based on the coordinate values at a plurality of rotation positions. It is possible to achieve highly accurate coordinate alignment.

According to the sixth aspect of the present invention, in the coordinate system for aligning the vision device and the industrial robot, the second positioning means is:
Since the one that rotates only the wrist axis of the industrial robot by 180 ° is adopted with the hand portion positioned at each point, the number of rotation positions can be minimized and the wrist rotation axis The calculation process of the coordinate value can be simplified.

In the coordinate aligning device for the vision device and the industrial robot according to claim 7, the number of points for sequentially positioning the hand parts of the industrial robot at different points in the visual field of the vision device is 4, and the conversion is performed. As the matrix acquisition means, between the coordinate system of the industrial robot and the coordinate system of the vision device based on the obtained coordinate values of the wrist rotation axes at the three points among the above four points and the coordinate values by the industrial robot. A coordinate transformation error obtaining means for obtaining a coordinate transformation error by performing coordinate transformation on the basis of the obtained matrix is adopted.
When the coordinates of the industrial robot or the coordinates of the vision device are nonlinearly distorted, it further includes conversion matrix correction means for correcting the above matrix so as to translate the coordinate values in the direction in which the error is reduced by 1/2. In addition, although the coordinate alignment accuracy in the vicinity of the above three points is slightly lowered, the coordinate alignment accuracy in the position away from the above three points can be improved,
As a result, it is possible to eliminate the variation in the coordinate alignment accuracy over the entire range of the visual field of the vision device.

According to another aspect of the present invention, there is provided a coordinate device for a vision device and an industrial robot, wherein the hand part of the industrial robot is provided with an auxiliary tool having a predetermined shape to be recognized, and the first coordinate value is set. As the acquisition means, the one that obtains the coordinate value of the predetermined position of the recognition target shape of the auxiliary tool at the plurality of rotational positions positioned by the second positioning means by the vision device is adopted, so the coordinate value of the wrist rotation axis is sub-valued. It can be obtained in pixel order, and the coordinate alignment accuracy can be further improved.

[0023]

Embodiments will be described in detail below with reference to the accompanying drawings showing embodiments. FIG. 2 is a schematic view showing an example of a robot system to which the coordinate aligning method of the present invention is applied. The hand unit is located at a predetermined position on the wrist shaft 2a of the industrial robot 2 that operates based on the operation command from the robot controller 1. 2b is provided. An image capturing device 4 including a video camera and the like is arranged below the translucent plate 3, and a vision device 5 that performs a predetermined process based on the image captured by the image capturing device 4 is provided. It is provided. It should be noted that data can be exchanged between the robot controller 1 and the vision device 5.
Further, the vision device 5 has a function of obtaining the coordinate value of the hand portion 2b, a function of calculating the coordinate value of the wrist rotation axis based on the coordinate value of the hand portion 2b at the 180 ° rotational symmetrical position,
A function that obtains a coordinate conversion matrix based on the coordinate values on the vision coordinate system and the coordinate values on the robot coordinate system at the point, and converts the coordinate values on the vision coordinate system to the coordinate values on the robot coordinate system to the robot controller 1. It has a function of supplying and a function of correcting the coordinate conversion matrix as necessary.

FIG. 3 is a schematic view showing the relationship between the wrist rotation axis of the industrial robot 2 and the hand section 2b, in which the hand section 2b is displaced from the wrist rotation axis. However,
This shift amount is an unknown value. FIG. 1 is a flow chart for explaining an embodiment of the coordinate aligning method of the present invention. In step SP1, the robot controller 1 gives an operation command to the industrial robot up to a point of known coordinate value on the robot coordinate system. 2 is operated, in step SP2, the coordinate value of the hand portion 2b on the vision coordinate system is obtained by the vision device 5 based on the image of the hand portion 2b captured by the image capturing device 4, and in step SP3 the industrial robot Only the wrist shaft 2a of No. 2 is rotated by 180 °, and in step SP4, the hand unit 2b captured by the image capturing device 4
The coordinate value of the hand portion 2b on the vision coordinate system is obtained by the vision device 5 based on the image of
In, the coordinate value of the wrist rotation axis is obtained based on the coordinate value obtained in step SP2 and step SP4,
In step SP6, it is determined whether or not the coordinate values of the wrist rotation axis corresponding to the three points are obtained, and if the number of points for which the coordinate values are obtained is less than 3, the process of step SP1 is repeated again. On the contrary, if the number of points for which the coordinate value is obtained is 3, the coordinate conversion matrix is calculated based on the coordinate value of 3 points on the vision coordinate system and the coordinate value of 3 points on the robot coordinate system in step SP7. A series of processing is finished as it is. Therefore, even if there is an unknown deviation between the wrist rotation axis and the hand section 2b, only the wrist axis is rotated to obtain the coordinate values of the hand section 2b at the positions shifted by 180 ° from each other. Since the intermediate point of the values is the coordinate value of the wrist rotation axis, it is possible to eliminate the influence of the above-mentioned deviation and obtain a coordinate conversion matrix having a significantly small error. That is, highly accurate coordinate alignment can be achieved.

[0025]

[Embodiment 2] FIG. 4 is a schematic view showing an example of a hand jig suitable for the coordinate aligning method of the present invention, in which a white circular area 2d is formed in the center of a jig 2c having an outer shape of a square. is there.
FIG. 5 is a flow chart for explaining this embodiment. The difference from the flow chart of FIG. 1 is that the vision device 5 uses the image of the hand unit 2b captured by the image capturing device 4 in steps SP2 and SP4. Instead of obtaining the coordinate values of the hand portion 2b on the vision coordinate system, the jig 2 captured by the image capturing device 4 is used.
Only the point for which the coordinate value of the center of gravity or the center position of the white circular region 2d on the vision coordinate system is obtained by the vision device 5 based on the image of c.

Therefore, in the case of this embodiment, the coordinate value of the wrist rotation axis can be obtained in the sub-pixel order, and the coordinate conversion matrix having a smaller error than that of the first embodiment can be obtained.

[0027]

[Embodiment 3] FIG. 6 is a flow chart for explaining still another embodiment of the coordinate adjusting method of the present invention. The difference from the flow chart of FIG. 1 is that step SP1 is repeated until the number of coordinates obtained is four. From the point where the processing of step SP5 is repeated, a point where the coordinate conversion matrix is obtained based on the coordinate value of any three points among the four points in step SP7, and the step SP8 is performed after the processing of step SP7 is performed.
In, the coordinate value of the remaining one point on the vision coordinate system is converted into the coordinate value on the robot coordinate system by the coordinate conversion matrix,
In step SP9, the difference is calculated based on the converted coordinate value and the actual coordinate value, and in step SP10, the difference is halved (in the opposite direction of the difference, 1 /
The coordinate transformation matrix is corrected so that the robot coordinate system moves parallel by 2), and the series of processing is terminated as it is.

Therefore, in the case of this embodiment, although the coordinate alignment accuracy in the vicinity of the above-mentioned three points is slightly deteriorated, looking at the entire range of the visual field of the vision device,
It is possible to significantly suppress the variation in the coordinate alignment accuracy. Specifically, when the coordinate conversion matrix is obtained based on the three points indicated by P1, P2, and P3 in FIG. 7, the coordinate alignment accuracy at points apart from the three points (for example, see P4 in FIG. 7). However, according to this embodiment, as shown in FIG.
By moving the robot coordinate system in parallel as indicated by X'-Y ', it is possible to suppress the variation in the coordinate alignment accuracy.

The present invention is not limited to the above-mentioned embodiment. For example, the coordinate value of the hand portion 2b is obtained with the wrist shaft 2a rotated by 180 °, and the wrist rotation is performed based on both coordinate values. Instead of getting the coordinate values of the axis, set the wrist axis 2a to 9
It is possible to obtain the coordinate values of the hand portion 2b in a state of rotating by any angle such as 0 ° and 120 °, and obtain the coordinate values of the wrist rotation axis based on these coordinate values. Various design changes can be made within the scope of the present invention.

[0030]

As described above, according to the first aspect of the present invention, the coordinate value of the wrist rotation axis is calculated based on the coordinate values at a plurality of rotation positions even if there is a deviation between the wrist rotation axis and the hand portion. By obtaining the above, it is possible to eliminate the influence of the above-mentioned deviation, and it is possible to achieve a unique effect that highly accurate coordinate alignment can be achieved.

The invention of claim 2 has a unique effect that the number of rotational positions can be minimized and the calculation process of the coordinate value of the wrist rotation axis can be simplified. According to the invention of claim 3, when the coordinates of the industrial robot or the coordinates of the vision device are distorted nonlinearly,
Although the accuracy of coordinate adjustment in the vicinity of the above three points is slightly lowered,
It is possible to improve the accuracy of coordinate alignment at positions apart from the above-mentioned three points, and further, it is possible to eliminate the variation in accuracy of coordinate alignment over the entire range of the visual field of the vision device.

The invention of claim 4 has a unique effect that the coordinate value of the wrist rotation axis can be obtained in the sub-pixel order and the coordinate alignment accuracy can be further improved.
According to the invention of claim 5, even if there is a deviation between the wrist rotation axis and the hand portion, by obtaining the coordinate values of the wrist rotation axis based on the coordinate values at a plurality of rotation positions, the influence of the deviation is obtained. Can be eliminated, and highly accurate coordinate alignment can be achieved.

The invention of claim 6 has a unique effect that the number of rotational positions can be minimized and the calculation process of the coordinate value of the wrist rotation axis can be simplified. According to the invention of claim 7, when the coordinates of the industrial robot or the coordinates of the vision device are distorted nonlinearly,
Although the accuracy of coordinate adjustment in the vicinity of the above three points is slightly lowered,
It is possible to improve the accuracy of coordinate alignment at positions apart from the above-mentioned three points, and further, it is possible to eliminate the variation in accuracy of coordinate alignment over the entire range of the visual field of the vision device.

The invention of claim 8 has a unique effect that the coordinate value of the wrist rotation axis can be obtained in the sub-pixel order, and the coordinate alignment accuracy can be further improved.

[Brief description of drawings]

FIG. 1 is a flowchart illustrating an embodiment of a coordinate matching method of the present invention.

FIG. 2 is a schematic diagram showing an example of a robot system to which the coordinate matching method of the present invention is applied.

FIG. 3 is a schematic diagram showing a relationship between a wrist rotation axis and a hand unit of the industrial robot.

FIG. 4 is a schematic view showing an example of a hand jig suitable for the coordinate alignment method of the present invention.

FIG. 5 is a flowchart illustrating another embodiment of the coordinate matching method of the present invention.

FIG. 6 is a flow chart for explaining still another embodiment of the coordinate matching method of the present invention.

FIG. 7 is a schematic diagram illustrating a specific example of the embodiment of FIG.

FIG. 8 is a schematic diagram illustrating a specific example of the embodiment of FIG.

[Explanation of symbols]

 1 Robot Controller 2 Industrial Robot 2a Wrist Axis 2b Hand Part 2c Jig 2d White Circular Area 5 Vision System

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location G05B 19/4093

Claims (8)

[Claims] 1. A vision device (2), wherein the hand part (2b) of an industrial robot (2) is positioned within the field of vision of the vision device (5) and the coordinate values of the hand part (2b) are obtained by the vision device (2). 5) is a method for performing coordinate adjustment between the industrial robot and the industrial robot, wherein the hand portion (2b) of the industrial robot is
Only the wrist axis (2a) of the industrial robot (2) is rotated in a state where the vision device (5) is sequentially positioned at at least three points different from each other, and the hand portion (2b) is positioned at each point. Coordinate values of the hand part (2b) at a plurality of rotational positions are obtained by the vision device (5),
The coordinate value of the wrist rotation axis is obtained based on the obtained coordinate values, and the industrial robot is based on the obtained coordinate value of the wrist rotation axis at at least three points and the coordinate value of the industrial robot (2). A coordinate alignment method between a vision device and an industrial robot, wherein a matrix for coordinate conversion between the coordinate system of (2) and the coordinate system of the vision device (5) is obtained. 2. Coordinates of the hand part (2b) at two rotation positions by rotating only the wrist shaft (2a) of the industrial robot (2) by 180 ° in a state where the hand part (2b) is located at each point. The method according to claim 1, wherein the value is obtained by a vision device (5), and the coordinate value of the wrist rotation axis is obtained based on the obtained two coordinate values. 3. A hand part (2) of an industrial robot (2)
The number of points for sequentially positioning b) at different points in the visual field of the vision device (5) is 4, the obtained coordinate values of the wrist rotation axis at 3 points, and the industrial robot (2).
A matrix for coordinate conversion between the coordinate system of the industrial robot (2) and the coordinate system of the vision device (5) is obtained based on the coordinate value according to 3. The vision device according to claim 1, wherein the coordinate conversion is performed to obtain a coordinate conversion error, and the matrix is corrected to move the coordinate value in parallel in a direction in which the error is reduced by 1/2 of the coordinate conversion error. Coordinate alignment method with industrial robot. 4. A hand part (2) of an industrial robot (2)
In b), an auxiliary tool (2 having a predetermined shape to be recognized)
c) is provided in advance, and only the wrist shaft (2a) of the industrial robot (2) is rotated in a state where the hand portion (2b) is positioned at each point, and the auxiliary tool (2c) at a plurality of rotational positions.
The coordinate value of a predetermined position of the recognition target shape (2d) is obtained by the vision device (5), and the coordinate value of the wrist rotation axis is obtained based on the obtained coordinate values. A method for aligning the coordinate between the vision device and the industrial robot described in. 5. The hand device (2b) of the industrial robot (2) is positioned within the field of view of the vision device (5), and the coordinate value of the hand device (2b) is obtained by the vision device (5) to obtain the vision device (5). 5) is a device for performing coordinate alignment between the industrial robot (2) and the hand part (2b) of the industrial robot (2) at at least three different points in the visual field of the vision device (5). Only the first positioning means (1) that is sequentially positioned and the wrist axis (2a) of the industrial robot (2) are rotated while the hand part (2b) is positioned at each point by the first positioning means (1). A second positioning means (1) and a first coordinate value acquisition means (5) for obtaining coordinate values of the hand part (2b) at a plurality of rotational positions positioned by the second positioning means (1) by the vision device (5). And the first coordinate Second coordinate value acquisition means (5) for obtaining the coordinate value of the wrist rotation axis (2b) based on the plurality of coordinate values obtained by the value acquisition means (5), and second of the wrist rotation axis at at least three points. Based on the coordinate value obtained by the coordinate value obtaining means (5) and the coordinate value by the industrial robot (2), the coordinate system between the industrial robot (2) and the coordinate system of the vision device (5) A coordinate alignment device for a vision device and an industrial robot, comprising: a conversion matrix acquisition means (5) for obtaining a matrix for coordinate conversion. 6. The second positioning means (1) rotates only the wrist shaft (2a) of the industrial robot (2) by 180 ° in a state where the hand portion (2b) is positioned at each point. A coordinate alignment device between the vision device according to Item 5 and an industrial robot. 7. A hand part (2) of an industrial robot (2)
The number of points for sequentially positioning b) at different points in the visual field of the vision device (5) is 4, and the conversion matrix acquisition means (5) obtains the wrist rotation axis at three of the four points. Obtaining a matrix for coordinate conversion between the coordinate system of the industrial robot (2) and the coordinate system of the vision device (5) based on the determined coordinate value and the coordinate value by the industrial robot (2). And a coordinate conversion error obtaining means (5) for obtaining coordinate conversion error by performing coordinate conversion on the basis of the other obtained matrix, and the coordinate value in the direction in which the error is reduced by 1/2 of the coordinate conversion error. 7. The coordinate alignment device for a vision device and an industrial robot according to claim 5, further comprising: a conversion matrix correction means (5) for correcting the matrix so as to translate the matrix. 8. A hand part (2) of an industrial robot (2)
In b), an auxiliary tool (2c) having a predetermined shape (2d) to be recognized is provided in advance, and the first coordinate value acquisition means (5) is positioned by the second positioning means (1). The vision device according to any one of claims 5 to 7 for industrial use, wherein the coordinate value of a predetermined position of the recognition target shape (2d) of the auxiliary tool (2c) at the rotational position is obtained by the vision device (5). Coordinate alignment device with robot.