JPH04141384A - Calibration method in positioning system using image processing device and device therefor - Google Patents

Abstract

PURPOSE:To automate calibration work by performing the actual measure adjustment of image processing information on the basis of the image of a jig detected by an image detecting means and the reference distance information, and bringing a robot coordinate system, and an image detecting means coordinate system in line with each other on the basis of the locus of the jig obtained by the image detecting means by moving the jig. CONSTITUTION:On the basis of a translucent plate 4, a lighting means 2 is disposed on either side and an image detecting means 3 id disposed below. A jig 12 is mounted to an industrial robot 1 for gripping a workpiece on the translucent plate 4, and the threshold value for binarization is set in such a way that the size of the jig computed on the basis of a signal taken in by the image detecting means 3 in the state of the jig 12 being moved into the preset position becomes the set value. The actual measure adjustment of image processing information is then performed on the basis of the image of the jig 12 taken in by the image detecting means 3 and the reference distance information, and both coordinate systems are brought in line with each other on the basis of the locus of the jig 12 obtained by the image detecting means 3 by moving the jig 12 afterwards.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a calibration method and apparatus for a system that performs positioning using an image processing device, and relates to a method for setting a threshold value for binarizing an image detection signal; This system automatically performs actual dimension matching to match the distance that cannot be obtained based on the image detection signal to the actual distance, and coordinate system matching work to match the robot coordinate system and the coordinate system of the image detection means. METHODS AND APPARATUS THEREOF.

<Prior art and problems to be solved by the invention> Conventionally, images of a predetermined range are captured by an image detection unit,
2. Description of the Related Art Systems that perform positioning by performing binarization processing or the like on a captured signal in an image processing unit have come to be applied to various devices including component supply devices.

FIG. 14 is a schematic diagram showing a conventional positioning system, in which an image detection section (92) is arranged above a workpiece support (91), and an image processing section ( 93) performs binarization processing to detect the type, position, etc. of the workpiece, and supplies the detection results to the robot controller (94) to generate robot operation commands and operate the industrial robot (95). By doing so, the workpiece (96) on the workpiece support base (91) can be gripped. In addition, the workpiece support stand (91) and the workpiece (9G)
The colors are set in advance to provide contrast and clarity.

Therefore, the threshold value for binarization processing, the workpiece support (
If the actual distance in 91) and the distance obtained based on the image detection signal, the coordinate system of the image detection unit < 92) and the coordinate system of the robot are properly set, the position information detected by the image detection unit By operating the industrial robot (95) based on this, accurate positioning of the workpiece (96) can be achieved.

However, when starting up the positioning system, there is no guarantee that the above settings are properly configured.
Calibration work must be performed to make these settings appropriate. Specifically, when the workpiece (96) is supported on the workpiece support base (91), the surrounding area is adjusted so that the binarized image obtained by the image processing unit (93) has a shape that is faithful to the workpiece (96). The threshold level is set while taking into account the brightness of the image detector, the aperture of the image detection unit (<92), etc. In addition, by capturing a scale image by the image detection unit (92) and teaching two points with a cursor or the like according to this scale, one pixel Set the hit dimensions. In addition, industrial robots (95
), draw a line parallel to the coordinate axis and a predetermined point within the field of view of the image detection unit (92), teach the relative relationship between these, and associate it with the position (95) of the industrial robot. By performing coordinate transformation processing, the coordinate system of the industrial robot and the coordinate system of the image detection unit are made to match.

By the way, during these operations, the field of view of the image detection unit (92) is partially covered by the industrial robot (95), making it impossible to directly capture the image of the tool gripping part of the industrial robot (95). Therefore, it is inevitable that the calibration work must be left to the manual work of an operator, which is disadvantageous in that the calibration work becomes extremely complicated. Further, a configuration is adopted in which the workpiece supporter (91) and the workpiece (96) are contrasted by the supporter (91) being made of a translucent plate, and a lighting device provided below the workpiece supporter (9I). However, it is completely impossible to eliminate the above-mentioned disadvantages.

Note that calibration work is required not only when starting up the positioning system, but also when replacing the robot hand, etc., and the complicated work described above is required each time calibration work is performed, so it is not necessary to perform the original work of the system. This will consume time and reduce system operating efficiency.

Furthermore, there is also the disadvantage that only an operator who fully understands the positioning system and the device incorporating the positioning system can perform the calibration work.

<Object of the invention> This invention was made in view of the above problems,
It is an object of the present invention to provide a new calibration method and device that can automate the calibration work and significantly simplify the work required of the operator.

Means for Solving the Problem> In order to achieve the above object, the calibration method of the first invention includes an illumination means on either side of a translucent plate as a reference, and an image detection means below. In addition to placing the means, a jig is attached to an industrial robot that grips a workpiece on a translucent plate, and the image detecting means is set while the jig is moved to a preset position. A threshold value for binarization is set so that the size of the jig is calculated based on the signal captured by the set value, and then the image of the jig captured by the image detection means and the reference value are set. The actual size of the image processing information is adjusted based on the distance information, and then the robot coordinate system and the imageless detection means coordinate system are matched based on the trajectory of the jig obtained by the image detection means by moving the jig. This is the way to do it.

In the calibration method of the second invention, the illumination means are arranged on three sides of a translucent plate, the jig has two holes, and the threshold value is set based on the size of the hole. , performing actual size alignment based on the distance between the centers of the holes calculated based on the signal captured by the image detection means and the distance between the centers of the holes given in advance,
This is a method in which the coordinate systems are matched based on the locus of the center of gravity position of one of the holes.

In the calibration method of the third invention, the illumination means is placed below a translucent plate, a predetermined position of the industrial robot also serves as a jig, and the signal captured by the image detection means is In this method, actual size alignment is performed based on the travel distance of the jig calculated based on this and a predetermined distance, and a matching operation of the coordinate system is performed based on the locus of the center of gravity position of the jig.

In the calibration method of the fourth invention, the tool holding part of the industrial robot also serves as a jig, and the tool holding part of the industrial robot also serves as a jig.
This is a method in which the wrist axis is operated, and the tool offset amount is further calculated based on the jig position calculated based on the signals captured by the image detection means before and after the wrist axis is operated.

A calibration device according to a fifth aspect of the invention includes an illumination means disposed on either side of the translucent plate and an image detection means disposed below the translucent plate, and a workpiece on the translucent plate. An industrial robot for gripping, a jig attached to the industrial robot, a robot control means for operating the industrial robot to move the jig to a preset position, and an image obtained based on the jig. 2 based on the image detection means to be detected and the signal obtained by the image detection means.
An image processing means for performing a value processing, a threshold setting means for setting a threshold for binarization so that the size of the jig obtained by the image processing means becomes a set value, and a threshold value setting means for setting a threshold for binarization so that the size of the jig obtained by the image processing means The robot coordinate system is calculated based on the jig's trajectory obtained by the image processing means and the jig's trajectory obtained by the image processing means. and coordinate system matching means for matching the coordinate system of the image detecting means and the coordinate system of the image detecting means.

In the calibration device of the sixth invention, the illumination means is arranged above a translucent plate, the jig has two holes, and the threshold value setting means sets the threshold value based on the size of the hole. The actual size adjustment is performed based on the distance between the centers of the holes obtained by the actual size adjustment means or the image processing means and the distance between the centers of the holes given in advance, and the coordinates The system matching means performs a matching operation of the coordinate system based on the locus of the center of gravity position of one of the holes.

In the calibration device of the seventh invention, the illumination means is disposed below the transparent plate, a predetermined position of the industrial robot also serves as a jig, and the actual size adjustment means is the image processing means. Actual dimension matching is performed based on the moving distance of the jig obtained by and a predetermined distance, and the coordinate system matching means performs the matching operation of the coordinate system based on the locus of the center of gravity position of the jig. It is.

In the calibration device of the eighth invention, the tool holding part of the industrial robot also serves as a jig, and the wrist axis of the industrial robot is operated, and the jig is obtained by image processing means before and after the movement of the wrist axis. The apparatus further includes tool offset calculation means for calculating a tool offset amount based on the position.

Effect> In the calibration method of the first invention, since the illumination means is arranged on either side of the light-transmitting plate and the image detection means is arranged below, the light-transmitting It is sufficient to attach a jig to an industrial robot that grips a workpiece on a flexible plate, and the calibration operation can be performed as follows. That is, the threshold value for binarization is set so that the size of the jig calculated based on the signal captured by the image detection means with the jig moved to a preset position becomes the set value. Then, the actual size of the image processing information is adjusted based on the image of the jig captured by the image detection means and the reference distance information, and then, by moving the jig, the image detection means The robot coordinate system and the image non-detecting means coordinate system are matched based on the trajectory of the jig obtained.

Therefore, after that, accurate positioning can be achieved by controlling the industrial robot based on the image processing information obtained by the image processing means.

In the calibration method of the second invention, since the illumination means and the image detection means are arranged on opposite sides of the translucent plate, a jig with two holes can be used for industrial use. It is only necessary to attach it to the robot, and the threshold value can be set and the actual size can be adjusted without causing the robot to operate.

Then, the coordinate system matching operation can be performed based on the locus of the center of gravity position of one of the holes as the industrial robot operates.

In the calibration method of the third invention, the illumination means and the image detection means are arranged below the transparent plate, and the predetermined position of the industrial robot also serves as a jig. This eliminates the need for jig installation work, further simplifying the work.

With the calibration method of the fourth invention, the tool offset amount can also be calculated by operating an industrial robot, and highly accurate calibration can be achieved regardless of the type of robot hand.

In the case of the calibration device of the fifth invention, since the illumination means is arranged on either side of the transparent plate and the image detection means is arranged below, the jig can be used as an industrial robot. The threshold value for binarization can be set by the threshold value setting means so that the size of the jig obtained by the image processing means for performing the binarization process is the set value. Then, the actual size of the image processing information can be adjusted by the actual size adjustment means based on the image of the jig obtained by the image processing means and the reference distance information, and the jig obtained by the image processing means The robot coordinate system and the image detection means coordinate system can be made to coincide with each other by the coordinate system matching means based on the locus of the robot coordinate system. .

With the calibration device of the sixth invention, since the illumination means is placed above the transparent plate, it is only necessary to attach a jig having two holes to the industrial robot. A threshold value is set based on the hole size by a threshold value setting means without operating an industrial robot,
By the actual size adjustment means, the distance between the centers of the holes obtained by the image processing means and in advance! Actual size adjustment can be performed based on the distance between the centers of the holes that have been prepared. Then, when the industrial robot is operated, the coordinate system matching means can perform a coordinate system matching operation based on the locus of the center of gravity position of one of the holes.

In the case of the calibration device according to the seventh aspect of the invention, the illumination means is placed below the translucent plate, and the predetermined position of the industrial robot also serves as a jig. No need to install tools.

With the calibration device of the eighth invention, the tool offset amount can also be calculated by operating an industrial robot, and highly accurate calibration can be achieved regardless of the type of robot hand.

<Example> Hereinafter, embodiments will be described in detail with reference to the accompanying drawings showing examples.

FIG. 2 is a schematic diagram showing the main parts of a positioning system to which the calibration method of the present invention is applied. The image detection system is equipped with a CCD camera, etc. below a workpiece support (4) made of a translucent plate. At the same time, a lighting device (2) is also placed at the bottom of the workpiece support (4). And a hand with a shield head (
11) Place the calibration jig (12) in the specified position.
is installed. ” 2. Calibration jig (
2) is a rectangular plate as a whole, as shown in FIG. 3, and has two holes (13) formed at a predetermined distance from each other.

FIG. 1 is a flowchart showing an embodiment of the calibration method of the present invention, in which the teaching position and shape data of the calibration jig (12) are input in step (2), and the calibration jig (12) is input in step (2). 12) is moved to the teaching position, and in step (2), an image of the calibration jig (12) is captured by the image detection section (3). Then, in step (2), the image-processed calibration jig (12
) is equal to a preset number of pixels, and if not, the threshold value for the binarization process is changed in step (2), and the process in step (2) is performed again.

]9 Conversely, if it is determined in step ■ that the number of pixels is equal to the preset number of pixels, then in step ■,
Calibration jig (12) subjected to image processing
The distance between the centers of the holes (3) is calculated based on the image, the size of one pixel is adapted to the actual dimension in step (■), and the calibration jigs (12) are orthogonal to each other in step (2). Operate parallel to each of the coordinate axes, obtain image processing information of one hole (13) at the start point and end point of each operation in step
In this step, a matrix for matching the robot coordinate system and the image detection section coordinate system is calculated by performing a predetermined calculation based on the obtained image processing information, and the series of processes is immediately terminated.

As is clear from the above explanation, the threshold value is automatically set, then the actual size is adjusted based on image processing information obtained from a workpiece of known size, and finally the calibration jig (12) is used. Coordinate system matching work can be performed by moving the coordinate systems in directions perpendicular to each other.

That is, the calibration operation, which could not be automated in the past, can be completely automated, and even an operator with no knowledge of positioning systems can easily accomplish the calibration.

<Example 2> Figure 6 shows an industrial robot (1), a lighting device (2), and a CCD to which the calibration method of the present invention is applied.
This is a schematic perspective view showing the relationship between an image detection unit (3) formed by a camera, etc., and a suction head (15) having a flange is attached to a predetermined position of an industrial robot (1).

Further, the illumination device (2) is a ring-shaped fluorescent lamp, and an image detection unit (3) is arranged below the center of the ring-shaped fluorescent lamp. In addition, the suction head (15) and the ring-shaped fluorescent lamp (
A workpiece support (4) is placed between the

FIG. 4 is a flowchart showing another embodiment of the calibration method of the present invention.
Adopting a preset threshold as a threshold for value conversion processing, the industrial robot (1) is operated in step (■) to bring the suction head 2 (15) close to the workpiece support (4), and step (2)
In this step, the process of step (2) is repeated until it is determined that the tip of the suction head (15) is clearly recognized with respect to the threshold value (see FIG. 5(A)). And step■
The position of the suction head (15) obtained in step 1 is set as the image recognition height from the workpiece support (4). Setting the image recognition height in this case is a process equivalent to setting a threshold value. Next, in step (2), the work whose size is known is moved to the image recognition height, and in step (2), the actual size of the image processing information is adjusted based on the binarized image of the work and the actual dimensions (step (see Figure 5 (B)), in step (2), the industrial robot (1) is moved parallel to each of the mutually orthogonal coordinate axes, and in step (2), image processing information at the start and end points of each movement is obtained (see Figure 5 (B)). (C)), in step (2), seven tricks are calculated to match the robot coordinate system and the image detection part coordinate system by performing predetermined calculations based on the obtained image processing information, and then a series of Finish the process.

As is clear from the above explanation, the threshold value is equivalently set by automatically setting the image recognition height, and then the actual cutting process is performed based on the image processing information obtained from the workpiece of known size. Then, the industrial robot (1) is finally moved in directions orthogonal to each other to perform the coordinate system matching work.

That is, the calibration operation, which could not be automated in the past, can be completely automated, and even an operator with no knowledge of positioning systems can easily accomplish the calibration.

<Embodiment 3> Fig. 10 is a schematic diagram showing the main parts of a positioning system to which the calibration method of the present invention is applied. ) is located, as well as an image detection unit (:
A ring-shaped lighting device (2) is arranged so as to surround 3). A suction head (lG) attached to the Z-axis shaft (17) of the SCARA type robot is also used as a hand and a calibration jig.

FIG. 7 is a flowchart 1 showing still another embodiment of the calibration method of the present invention, in which the suction head (16) is brought into contact with the upper surface of the workpiece support base (4) in step Binarization processing is performed on the captured signal from the detection unit (3) based on a set threshold value, and in step (2), the pixel area of the binarized image is determined by Suction head (I6) based on the threshold value that can be recognized as
It is determined whether the threshold value has been reached (the number of pixels), and if it has not been reached, the threshold value is changed in step (2), and then the process of step (2) is repeated again. If it is determined that the pixel area of the binarized image has reached the preset pixel area, in step Absolute coordinates 01. (Ol, L, 012) (see Fig. 8), and in step 2, move the Z holder (17) to raise the suction head (1G), rotate the wrist shaft 1800 times, and raise the suction head again. (16) is brought into contact with the workpiece support (4), and in step (2), absolute coordinates 02 (021, 022) (see Fig. 8) in the image detection unit coordinate system of the suction head (16) are determined based on the image processing results. Then, in step ■, the above absolute coordinates 01,0
By subtracting 2 and performing the calculation 0O=01 +02, the coordinate of the rotation axis in the image detection unit coordinate system is 00 (
O[11,002) (see FIG. 8) is obtained. Then, in step ■, the rotation matrix (0, a, 0.0) for rotation is created by giving an offset to the tool coordinates.
After the suction head (16) is raised in step [phase], the vertical axis is rotated 180 degrees to bring the suction head (16) into contact with the workpiece support (4) again, and the image is removed in step (3). Based on the processing results, the suction head (16
) in the image detection unit coordinate system oy (Oyl,
Oy2) (see Figure 8), and after raising the suction head (16) in step @, rotate the wrist axis 180 degrees in the opposite direction and place the head (16) in front of the eye again on the workpiece support base (4). Contact and offset the tool coordinates in step ■! :8i, to obtain the rotation matrix (0,0,b,Q) for rotation. Then, in step (2), after raising the suction head (16), the wrist axis is rotated 180° and the suction head (16) is raised again.
6〉 is brought into contact with the workpiece support (4), and in step ③, the absolute coordinate Oz (Ozl, 0
z2) (see Figure 8) is obtained.

After that, in step ■, the obtained absolute coordinates 02,
The tool coordinate offset amount (0,
YL, Zl, 0) are calculated. Although not shown in the flowcharts up to this point, it is possible to increase the accuracy of absolute coordinates by setting a threshold each time the suction head (16) comes into contact with the workpiece support (4) in order to obtain absolute coordinates. preferable. Further, to explain in detail the calculation of the above offset amount, the absolute coordinate Z of the rotation axis when the Z axis is offset is Z = (Oz +02)/2,
When the Y-axis is offset, the absolute coordinate Y of the rotation axis is Y = (Oy +02)/2, so the amount of offset from the rotation axis center 00 is y = Y - 00, z
=Z-00. Here y= (yll, y12
), z= (z 1.1. z 12), then
Tool coordinate offset amount Y1. Z] can be obtained by performing the following calculation. After the tool offset amount has been obtained as described above, in step 2, raise the suction head (16) by 1" and then bring the suction head (1G) into contact with any point on the workpiece support (4). , In step ■, the suction head (
16) absolute coordinate Pir(x
ir, yir) and Pi in the robot coordinate system
a(xia, yia) (i=1.2.3) is obtained, and the process of step @[exist] is repeated until it is determined in step (2) that the absolute coordinates of three points have been obtained. If it is determined that the absolute coordinates of the three points have been obtained in step (2), actual size alignment is performed in step [phase] based on the absolute coordinates of the three points in both coordinate systems, and step (2)
A transformation matrix from the image detection unit coordinate system to the robot coordinate system is calculated based on the absolute coordinates of the three points in both coordinate systems, and the series of processing is completed.

To explain in detail the calculation of the above transformation matrix, as shown in FIG. 9, the image detection unit coordinate system (x, y) and the robot coordinate system (X, Y) are given, and the image detection unit coordinate system The coordinates of the origin 0 in the robot coordinate system are (
Ox, Oy ), the coordinates (X2.Y2) of point P1 in the robot coordinate system can be obtained by performing the following calculation (where X1y1 is the coordinate of point P1 in the image detection unit coordinate system). ).

Moreover, the three points obtained above are P1 in FIG. ．． P2゜P3
In this case, if we match the origins of both coordinate systems, the X axis is the X axis rotated by (α-β), so let the X component of X be xi and the Y component be xj. Then, . Also, since the y-axis is the X-axis rotated by ±90° (+ in the case of the same species and - in the case of different species), let the X component of y be yk, and the X component be yno. In this case, (however, K = 1 in the case of the same lineage, and K = -1 in the case of the different lineage).

Therefore, the above determinant is becomes.

FIG. 11 is a diagram illustrating an application example of the calibration method of the present invention, and shows that calibration should be performed even when the position of the image detection unit (3) changes from the position shown by the broken line to the position shown by the solid line. Just by giving instructions,
A calibration operation corresponding to the new image detection section (3) can be automatically performed. In addition, lighting equipment (
Even when the illuminance of 2) decreases, the optimal threshold value can be automatically set by simply instructing that calibration should be performed.

<Embodiment 4> FIG. 12 is a block diagram showing an embodiment of the calibration device of the present invention, in which a lighting device (2 ), an image detection unit (3), and an industrial robot (1) that has a suction head (1G) that grips the workpiece on the workpiece holder (4) and the suction head (16) to a preset position. A robot controller (5) operates the industrial robot (1) to move the industrial robot (1), and a robot controller (5) operates the industrial robot (1) based on signals obtained by the image detector (3) based on the suction head (16).
An image processing unit (3a) that performs value conversion processing, etc.;
A threshold setting unit (3b) sets a threshold value for binarization so that the size of the suction spatula obtained by 3a)" (1G) or a set value, and a suction spatula obtained by the image processing unit (3a) The actual size adjustment unit (3c) performs actual size adjustment of image processing information based on the image of the head (16) and reference distance information, and the trajectory of the suction head (1G) obtained by the image processing unit (3a). a coordinate system-shikibe (3d) that matches the robot coordinate system and the image detection unit coordinate system based on the coordinate system;
The tool offset calculating section (3e) calculates the tool offset based on the position of the suction head (IB) obtained by the image processing section (3a) before and after the movement of the wrist axis.

The operation of the calibration device having the above configuration is as follows.

The lighting device (2) is turned on, the industrial robot (1) is operated by the robot control unit (5), and the suction head (]6
) to a preset position. In this state, the image processing section (3a) applies signals obtained by the image detection section (3) based on the suction head (16).
), and the threshold value setting unit (3b) sets a threshold value for the binarization so that the size (pixel area) of the suction head (IB) obtained by the image processing unit (3a) becomes the set value. Set. After that, the industrial robot (1) is operated to further move the suction spatula l'' (1G), and based on the position of the suction head <16) obtained by the image processing unit (3a) before and after the movement of the hand-color axis. The tool offset calculation unit (3e) calculates the tool offset amount, and the actual size adjustment unit calculates the tool offset amount based on the image of the suction head (16) obtained by the image processing unit (3a) and the reference distance information. The actual size of the image processing information is adjusted by (3c).

Then, an image of the suction head (16) obtained by further moving the suction head (16), or an image of the suction head (16) obtained when the suction head (16) is moved for actual size adjustment (
Based on the locus of the suction head (16) obtained from the image 16), seven tricks for matching the robot coordinate system and the image detection part coordinate system are calculated using the coordinate system-base part (3d).

FIG. 13 is a timing chart explaining the calibration operation, in which the suction head (]6) moves to the first point of the workpiece support base (4) with the robot operation, and the image processing unit (3a) At the same time as the threshold value is set, the coordinate values are calculated, and each time the coordinate value is moved to a subsequent point, the coordinate values are calculated, and the calculated coordinate values are sent, and the suction head (16) returns to the standby position. Moving. After that, the offset amount is calculated and the suction head (
After performing the movement and calculation of coordinate values in step 16), a coordinate transformation matrix is calculated.

However, even if the coordinate values for calculating the coordinate transformation matrix are not specially calculated, the coordinate values for calculating the offset amount can be used, and in this case, the suction head (16
) can be moved by 4 points.

Therefore, after that, it is only necessary to perform matrix calculation on the coordinates obtained in the image detection unit coordinate system and supply the result to the robot control unit (5), and the suction head (1G) of the industrial robot (1) can be accurately moved. Can be positioned. Therefore, if applied to a component supply device, the suction head (IB) can be accurately moved to the component position recognized by the image detection section (3) and the image processing section (3a), and good component supply can be achieved. It can be achieved. However, even if the device is other than the parts supply device, the image detection section (3) and the image processing section (3a)
Of course, the present invention can be similarly applied to any device that performs positioning using.

<Effects of the Invention> As described above, the first invention is unique in that most of the calibration work is automated, greatly reducing the work of the operator, and calibration can be achieved even without understanding the positioning system. It has the effect of

The second invention has the unique effect that good calibration can be achieved even if the number of moving parts of the jig is small by simply mounting the jig on the industrial robot.

In addition to the effects of the first invention, the third invention has the unique effect of ensuring a wide robot operating area.

The fourth invention has the unique effect of being able to achieve good calibration even when the robot hand is changed.

The fifth invention has the unique effect of automating most of the calibration work, greatly reducing the work of the operator, and achieving calibration even without understanding the positioning system.

The sixth aspect of the invention has the unique effect that good calibration can be achieved even if the number of moving parts of the jig is small just by attaching the jig to the industrial robot.

In addition to the effects of the fifth invention, the seventh invention has the unique effect of ensuring a wide robot operating area.

The eighth invention has the unique effect of being able to achieve good calibration even when the robot hand is changed.

[Brief explanation of drawings]

Figure 1 is a flowchart showing an embodiment of the calibration method of the present invention, Figure 2 is a schematic diagram showing the main parts of a positioning system to which the calibration method of the present invention is applied, and Figure 3 is a plane view of the jig. Figure 4 is a flowchart showing another embodiment of the calibration method of the present invention, Figure 5 is a diagram explaining the calibration operation, and Figure 6 is an industrial robot to which the calibration method of the present invention is applied. 7 is a flowchart showing still another embodiment of the calibration method of the present invention, and FIGS. 8 and 9 are A diagram explaining the calibration operation; FIG. 1O is a schematic diagram showing the main parts of a positioning system to which the calibration method of the present invention is applied; FIG. 11 is a diagram explaining an example of application of the calibration method of the present invention; FIG. 12 is a block diagram showing an embodiment of the calibration device of the present invention, FIG. 13 is a timing chart explaining the calibration operation, and FIG. 14 is a schematic diagram showing a conventional positioning system. (1)...Industrial robot, (2)...Lighting device,
(3)...image detection section, (3a)...image processing section,
(3b)...Threshold setting section, (3c)...Actual size adjustment section, (3d)...Coordinate system-base section, (3e)...Tool offset calculation section, (4)...
Workpiece support made of a translucent plate, (5)...Robot control unit, (12)...Calibration jig, (13)...
・Holes, (15) (16)...Suction head patent applicant Daikin Industries, Ltd. agent

Claims (1)

[Claims] 1. An illumination means (2) is arranged on either side of a translucent plate (4), and an image detection means (3) is disposed below the translucent plate (4). Jigs (12) (15) (1) are attached to an industrial robot (1) that grips a workpiece on a plate (4) with
6) is attached and the jigs (12), (15), and (16) are moved to preset positions, and the jig is calculated based on the signal captured by the image detection means (3). A threshold for binarization is set so that the sizes of (12), (15), and (16) become the set values, and then the jigs (12), (15), and ( 1
The actual size of the image processing information is adjusted based on the image of 6) and the reference distance information, and then the jig (12) (
15) By moving (16), the image detection means (
3) A calibration method characterized by matching the robot coordinate system and the image detection means coordinate system based on the trajectories of the jigs (12), (15), and (16) obtained in step 3). 2. The illumination means (2) is placed above the transparent plate (4), the jig (12) has two holes (13), and the size of the holes (13) Based on the distance between the centers of the holes (13) calculated based on the signal captured by the image detection means (3) and the distance between the centers of the holes (13) given in advance. 2. The calibration method according to claim 1, wherein actual size alignment is carried out using the same method, and the matching operation of the coordinate systems is carried out based on the locus of the center of gravity position of one of the holes (13). 3. The illumination means (2) is arranged below the transparent plate (4), and the illumination means (2) is placed at a predetermined position (16) on the industrial robot (1).
) also serves as a jig, and performs actual size adjustment based on the moving distance of the jig (16) calculated based on the signal captured by the image detection means (3) and a predetermined distance, The calibration method according to claim 1, wherein the coordinate system matching operation is performed based on the locus of the center of gravity position of the jig (16). 4. The work holding part (16) of the industrial robot (1) also serves as a jig, and the wrist axis of the industrial robot (1) is operated, and images are captured by the image detection means (3) before and after the movement of the wrist axis. The jig (16
) The calibration method according to claim 3, further comprising calculating the tool offset amount based on the position of the tool. 5. Illumination means (2) disposed on either side of the translucent plate (4) and image detection means (3) disposed below, and the translucent plate (4) Industrial robot (1) that grips the workpiece above and industrial robot (1)
The jigs (12) (15) (16) attached to the
12) A robot control means (5) that operates the industrial robot (1) to move (15) and (16) to a preset position, and a binary value based on the signal obtained by the image detection means (3). Image processing means (3a) that performs conversion processing
and a jig (12) obtained by the image processing means (3a)
(15) A threshold setting means (3b) for setting a threshold for binarization so that the size of (16) becomes a set value, and jigs (12) (15) obtained by an image processing means (3a). )
(16) Actual size adjustment means (3c) that performs actual size adjustment of image processing information based on the image and reference distance information.
); and coordinate system matching means (3d) for matching the robot coordinate system and the image detection means coordinate system based on the trajectory of the jig obtained by the image processing means (3a). . 6. The illumination means (2) is arranged above the translucent plate (4), the jig (12) has two holes (13), and the threshold setting means (3b) The threshold value is set based on the size of the hole (13), and the actual size adjustment means (3c) determines the distance between the centers of the holes (13) obtained by the image processing means (3a) and the distance given in advance. Actual size alignment is performed based on the distance between the centers of the holes (13), and the coordinate system matching means (3d) performs the matching operation of the coordinate systems based on the locus of the center of gravity position of one hole (13). The calibration device according to claim 5, wherein the calibration device is: 7. The illumination means (2) is arranged below the transparent plate (4), and the illumination means (2) is placed at a predetermined position (16) on the industrial robot (1).
) also serves as a jig, and the actual size adjustment means (3c) performs actual size adjustment based on the moving distance of the jig (16) obtained by the image processing means (3a) and a predetermined distance. 6. The calibration device according to claim 5, wherein the coordinate system matching means (3d) performs the matching operation of the coordinate systems based on the locus of the center of gravity position of the jig (16). 8. The work holding part (16) of the industrial robot (1) also serves as a jig, and the wrist axis of the industrial robot (1) is operated, and the image processing means (3a) is used before and after the movement of the wrist axis.
Based on the position of the jig (16) obtained by
Claim 7 further includes a tool offset calculation means (3e) for calculating the offset amount.
Calibration device as described in section.