WO2021048579A1 - System and machine tool - Google Patents

Abstract

The present invention is provided with: a machine tool 10; a robot 25 having a camera 31; and a carrying device 35 on which the robot 25 is mounted, wherein an identification figure is disposed within a machining area of the machine tool 10.

Description

\\ 020 21/048579 卩 (: 17132019/001004

[Document name] Statement

[Title of Invention] System and Machine Tool [Technical Field]

[00 01] This disclosure consists of a machine tool that processes a work machine, a robot that works on the machine tool, and a transfer device that can move to a work position set for the machine tool. Regarding the system to be used.

[Background technology]

[00 0 2] Conventionally, as an example of the above-mentioned system, a system disclosed in Japanese Patent Application Laid-Open No. 201 7-1 32002 (Japanese Patent Application Publication No. 1, Patent Document 1 below) is known. In this system, the automatic guided vehicle equipped with the robot moves to the work position set for the machine tool, and at that work position, the robot executes work such as attaching and detaching the work to the machine tool. To.

[00 0 3] In such a system, one robot moved by an automatic guided vehicle can perform work such as attaching / detaching a work to a plurality of machine tools. Compared to the case where the robot is arranged in a fixed state, the degree of freedom of the machine tool layout is increased, so the machine tool layout can be set to a layout that can further improve production efficiency. .. In addition, compared to the conventional system in which the robots are arranged in a fixed state, it is possible to work on more machine tools with one mouth pot, so the equipment cost can be reduced. be able to.

[00 0 4] On the other hand, since the automatic guided vehicle has a structure of self-propelling using wheels, its positioning accuracy of stopping at the working position is not necessarily high. Therefore, in order for the robot to perform accurate work on the machine tool, it is set at the posture of the robot when the automatic guided vehicle is positioned at the work position and at the time of so-called teaching, which is a control standard. It is necessary to compare with the reference posture of the robot, detect the amount of error, and correct the working posture of the robot according to the amount of error.

[00 0 5] As a technique for correcting the posture of such a robot, a position correction method as disclosed in Japanese Patent Application Laid-Open No. 2016-221622 (Japanese Patent Application Publication, Patent Document 2 below) has been conventionally used. Are known. Specifically, in this position correction method, a visual target consisting of two calibration markers is placed on the outer surface of the machine tool, and the visual target is measured by a camera provided on the movable part of the robot. Based on the image obtained by imaging and the position and orientation of the camera, the relative positional relationship between the robot and the machine tool is measured, and based on the measured positional relationship, the robot's working posture. Is to correct.

[Prior Art Document]

[Patent Document]

[00 0 6]

[Patent Document 1] Japanese Patent Application Laid-Open No. 201 7-1 32002 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-221622 [Summary of Invention]

[Problems to be Solved by the Invention]

However, in the conventional position correction method described above, for example, a robot hand or the like is inserted into the machine tool, and the hand is used to attach or detach the work to or from the chuck of the machine tool. At that time, there was a problem that the posture of the robot performing this attachment / detachment work could not be corrected accurately.

[00 0 8] \\ 0 2021/048579 卩 (: 17132019/001004 That is, the automatic guided vehicle is configured to move by the movement of wheels with a relatively high degree of freedom, so the mounting surface on which the robot is mounted is It has the characteristic that it easily tilts with respect to the floor surface, and that the tilt easily changes according to changes in the posture of the robot to be mounted, in other words, according to changes in the position of the center of gravity of the robot. ..

[0 0 0 9] Therefore, when the robot takes a posture in which the hand is advanced into the machine tool when attaching / detaching the work described above, in other words, the arm of the robot is the automatic guided vehicle. The inclination of the above-mentioned mounting surface when a large overhang occurs from the above is based on the assumption that the robot hand is outside the machine tool and the arm is not overhanging or overhanging from the automatic guided vehicle. Is larger than the inclination when the amount is small.

[0 0 1 0] Therefore, as in the conventional position correction method described above, a visual target, which is a calibration marker, is arranged on the outer surface of the machine tool, and the robot is outside the machine tool. Even if the position correction amount (posture correction amount) of the robot is acquired, the obtained position correction amount is used to attach / detach the work piece, which is executed when the robot hand is inside the machine tool. Regarding the movement, the posture of the robot cannot be corrected accurately.

[0 0 1 1] If the posture of the robot when attaching and detaching the work cannot be corrected accurately, the robot hand cannot be accurately positioned with respect to the chuck. For example, the chuck is described above. In the case of a chuck such as a collet chuck where the movement allowance (stroke) of the grip is very small, that is, the clearance between the work and the chuck is very small, the work is surely applied to the chuck. There is a possibility that it cannot be grasped.

[0 0 1 2] If the work cannot be reliably attached and detached, the operating rate of the system will decrease. In this system, it is not possible to realize unmanned operation with high reliability and high production efficiency.

[0 0 1 3] Further, in the position correction method disclosed in Patent Document 2, since each of the two calibration markers is imaged by a camera, the operation of the robot for imaging the calibration markers is performed. There is also a problem that the production efficiency in the system is lowered because the time is long.

[Means for solving problems]

[0 0 1 4] Therefore, the present disclosure has a machine tool that performs predetermined processing on the work, a camera that captures an image, and an action unit that acts on the work, and the machine tool has a function. According to an operation program that includes a robot that performs work, a transfer device that is equipped with the robot and is configured to be movable to a work position set for the machine tool, and a preset operation command. The work start posture, the imaging posture in which the camera is made to face the identification figure for posture correction provided in the machine tool, and the imaging posture in which the identification figure is imaged by the camera, and the work. A control device configured to sequentially take one or more working postures for operating the working unit is provided, and the working start posture, the imaging posture, and the working posture are the teaching operations of the robot. This is a preset system, in which the identification figure is formed on a predetermined plane and arranged in the machining area of the machine tool, and the control device is used during the teaching operation. When the robot is moved to the imaging posture, the image of the identification figure captured by the camera is stored in advance as a reference image, and when the robot is operated according to the operation program, the transport device is used. The above work \\ 0 2021/048579 The image of the identification figure captured by the camera after shifting the robot from the work start posture to the imaging posture while moving to the position (: 17132019/001004), and Based on the reference image, the amount of error in the position of the camera between the current posture of the robot and the posture during the teaching operation, which is orthogonal to each other set in a plane parallel to the identification figure. The amount of positional error of the camera in the two axial directions and the amount of rotation error of the camera around the vertical axis orthogonal to the plane are estimated, and the action in the working posture is based on each estimated error amount. The present invention relates to a system configured to calculate a correction amount for a part and correct the position of the action part in the working posture based on the calculated correction amount.

[0 0 1 5] According to this system, after the transfer device is appropriately moved to a working position set for the machine tool, the robot is controlled by the control device, and a preset operation is performed. By sequentially taking a working posture according to an operation program including commands, work such as attaching / detaching a work to a machine tool is executed.

[0 0 1 6] The operation of the robot is controlled according to the operation program, and after the transfer device is moved to the work position, the robot starts the operation from the work start posture, and then is provided in the machine tool. By facing the camera with respect to the identification figure for posture correction, the camera takes an imaging posture for capturing the identification figure, and then operates so as to sequentially take one or more working postures. The work start posture, the imaging posture, and the work posture are set in advance by teaching the robot. The identification figure is formed on a predetermined plane and is arranged in the machining area of the machine tool. Also, when the robot takes the imaging posture, the camera faces the identification figure, that is, the camera is in a posture in which the lens and the identification figure are substantially parallel to each other.

Then, the control device stores in advance the image of the identification figure captured by the camera as a reference image in a state where the robot is shifted to the imaging posture during the teaching operation. Next, when the robot is operated according to the operation program, the image of the identification figure captured by the camera and the reference image in a state where the robot is shifted from the work start posture to the imaging posture. Based on, the amount of error in the position of the camera between the current posture of the robot and the posture during the teaching operation, which is orthogonal to each other set in a plane parallel to the identification figure. The amount of positional error of the camera in the biaxial direction and the amount of rotation error of the camera around the vertical axis orthogonal to the plane are estimated, and based on each estimated amount of error, with respect to the acting part in the working posture. The correction amount is calculated, and the position of the working portion in the working posture is corrected based on the calculated correction amount.

[0 0 1 8] In this system, the working posture of the robot is corrected by using the identification figure placed in the machining area of the machine tool that the robot actually works on. The work posture can be corrected accurately, so that the robot can perform the work accurately even in a work that requires high operation accuracy.

[0 0 1 9] And, by performing the work with high accuracy by the robot in this way, the system operates at a high operating rate without causing unnecessary interruption, and as a result, according to the system, it is reliable. It is possible to achieve automation with high performance and high production efficiency.

[0 0 2 0] In addition, the robot that operates according to the operation program is configured to execute this in one operation when the identification figure is imaged by the camera, so it is shorter than before. Accurate correction can be performed in time.

[0 0 2 1] In addition, another disclosure is that a robot having a camera for capturing an image including an identification figure provided in a machine tool and an acting part acting on a work is mounted on the robot. The transport device for transporting the robot to the first position where the work can be held in front of the robot. \\ 0 2021/048579 卩 (: 17132019/001004) After transporting to the first position, an image including the identification figure provided on the machine tool is imaged by the force machine, and the position of the identification figure in the image is taken. According to the information, the second position of the action part on the X-axis and the V-axis in the cubic element space of the X-axis, the V-axis, and the axis is corrected by making the action part perform linear movement and rotational movement. A machine tool for machining a work, in which the working portion acts on the work inside the machine tool after the second position is corrected, and the identification figure is arranged in the machining area of the machine tool. Related to machine tools.

【Effect of the invention】

[0 0 2 2] As described above, according to the system according to the present disclosure, the working posture of the robot is corrected by using the identification figure arranged in the machining area of the machine tool in which the robot actually works. Therefore, the working posture can be corrected accurately, so that the robot can perform the work with high accuracy even in the work requiring high operation accuracy.

[0 0 2 3] In this way, the robot performs accurate work, and the system operates at a high operating rate without causing unnecessary interruption. As a result, according to the system. , Highly reliable and highly efficient automation can be achieved.

[0 0 2 4] In addition, when the robot operates according to the operation program, the position of the action part of the robot can be corrected by performing the operation of capturing the identification figure with the camera once. Compared to the conventional method, accurate correction can be performed in a short time.

[Simple explanation of drawings]

[0 0 2 5]

FIG. 1 is a plan view showing a schematic configuration of a system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a system according to the present embodiment.

FIG. 3 is a perspective view showing an automatic guided vehicle and a robot according to the present embodiment.

FIG. 4 is an explanatory diagram for explaining the imaging posture of the robot according to the present embodiment.

FIG. 5 is an explanatory diagram showing an identification figure according to the present embodiment.

FIG. 6 is an explanatory diagram for explaining a correction amount calculation method in the present embodiment.

FIG. 7 is an explanatory diagram for explaining a correction amount calculation method in the present embodiment.

FIG. 8 is an explanatory diagram for explaining a correction amount calculation method in the present embodiment.

FIG. 9 is an explanatory diagram for explaining position correction in the present embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION

[0 0 2 6] Hereinafter, specific embodiments will be described with reference to the drawings.

As shown in Fig. 1 and Fig. 2, the system 1 of this example is a machine tool 10 and a material stocker 2 0 as a peripheral device and a product stocker 2 1 and an automatic guided vehicle 3 5 , The robot 2 5 mounted on this automatic guided vehicle 35, the camera 3 1 mounted on the robot 2 5, and the control device 4 0 that controls the robot 2 5 and the automatic guided vehicle 3 5 Will be done.

As shown in FIG. 4, the machine tool 1 0 is provided with a spindle 1 1 to which a chuck 1 2 for gripping a work (\\') is mounted, and the spindle 1 1 is in the vertical direction. It is a so-called vertical N0 (numerical control) lathe installed along the line, and it is possible to perform turning on the work (\\'). In addition, a tool presetter 1 3 equipped with a contactor 1 4 and a support bar 1 5 for supporting the contactor 1 4 is provided in the vicinity of the spindle 1 1, and the support bar 1 5 is located on the axis of the spindle 1 1. Along the line, it is provided so that it can move forward and backward with respect to the processing area, and a ceramic display board 1 6 is provided on the end face on the processing area side, and the identification figure shown in Fig. 5 is provided on this display board 1 6. Is drawn. The display board 16 is provided so as to be located on a horizontal plane.

[0 0 2 9] \\ 0 2021/048579 卩 (: 17132019/001004 In addition, Fig. 4 shows the state where the support bar 1 5 and the contact 1 4 have advanced into the machining area, but the support bar 1 5 and the contact 1 1 With the contacts 1 4 and the display board 1 6 retracted in the storage area, the contacts 1 4 and the display board 1 6 are separated from the application area by closing the shutter 1 7 with the 4 retracted. To.

[0 0 3 0] Further, the identification figure of this example has a matrix structure in which a plurality of square pixels are arranged two-dimensionally, and each pixel is displayed in white or black. In Figure 5, the black pixels are shaded. Some of these identification figures are called entry markers and entry pr 1 1 chome & _8. If the identification figure is small, a lens may be provided on the identification figure so that the enlarged image can be captured by the camera 31 described later.

[0 0 3 1] The material stocker 20 is arranged on the left side of the machine tool 10 in FIG. 1, and a plurality of materials processed by the machine tool 10 (a device for stocking a work before machining). In addition, the product stocker 2 1 is arranged on the right side of the machine tool 10 in Fig. 1, and is a plurality of products or semi-finished products processed by the machine tool 10 (processed work'). It is a device that stocks.

As shown in FIG. 1, the automatic guided vehicle 3 5 is equipped with the robot 2 5 on a mounting surface 3 6 which is the upper surface thereof, and an operation panel which can be carried by an operator. 3 7 is attached. The operation panel 37 is equipped with an input / output unit for inputting / outputting data, an operation unit for manually operating the automatic guided vehicle 35 and the robot 25, and a display capable of displaying a screen.

[0 0 3 3] In addition, the automatic guided vehicle 35 is equipped with a sensor (for example, a distance measurement sensor using laser light) that can recognize its own position in the factory, and the control device 40 Under the control of the above-mentioned machine tool 10, the material stocker 20 and the product stocker 2 1 are configured to run on an automated guided vehicle in the factory including the area where the machine tool 10 and the product stocker 2 1 are arranged. It goes through each working position set for each of the machine tool 10 and the material stocker 2 0 and the product stocker 2 1.

As shown in FIGS. 1 and 3, the robot 2 5 is articulated with three arms, a first arm 2 6, a second arm 27, and a third arm 28. It is a type robot, and a hand 2 9 as an end effector is attached to the tip of the 3rd arm 28, and one camera 3 1 is attached via a support bar 30.

As shown in FIG. 2, the control device 4 0 includes an operation program storage unit 4 1, a moving position storage unit 4 2, an operation posture storage unit 4 3, a map information storage unit 4 4, and a reference image. It consists of a storage unit 4 5, a manual operation control unit 4 6, an automatic operation control unit 4 7, a map information generation unit 48, a position recognition unit 4 9, a correction amount calculation unit 50, and an input / output interface 5 1. Then, the control device 40 uses the machine tool 10, the material stocker 2 0, the product stocker 2 1, the robot 25, the camera 3 1, and the automatic guided vehicle 3 5 through the input / output interface 5 1. And it is connected to the operation panel 3 7.

[0 0 3 6] The control device 40 is composed of a computer including 0 11, scale] ^, scale 〇] ^, etc., and is composed of the manual operation control unit 4 6, the automatic operation control unit 4 7, and a map. The functions of the information generation unit 48, the position recognition unit 49, the correction amount calculation unit 50, and the input / output interface 5 1 are realized by a computer program, and the processing described later is executed. In addition, the operation program storage unit 41, the movement position storage unit 4 2, the operation posture storage unit 4 3, the map information storage unit 4 4 and the reference image storage unit 4 5 are composed of appropriate storage media such as R AM. In this example, the control device 40 is attached to the automatic guided vehicle 35, and is connected to the machine tool 10, the material stocker 2 0 and the product stocker 2 1 by appropriate communication means, and the robot 25, the camera 3 1, automatic guided vehicle 3 5 and operation panel 3 7 are connected by wire or wireless. However, the present invention is not limited to this aspect, and the control device 40 may be arranged at an appropriate position other than the automatic guided vehicle 35. In this case, the control device 40 is appropriately connected to each part by communication means. \\ 0 2021/048579 卩 (: 17132019/001004

[0 0 3 7] The manual operation control unit 4 6 is a functional unit that operates the automatic guided vehicle 35, the robot 25, and the camera 3 1 according to an operation signal input from the operation panel 3 7 by the operator. Is. That is, the operator can manually operate the automatic guided vehicle 35, the robot 25, and the camera 3 1 using the operation panel 3 7 under the control of the manual operation control unit 46.

[0 0 3 8] The operation program storage unit 4 1 generates an automatic driving program for automatically driving the automatic guided vehicle 35 and the robot 2 5 at the time of production, and map information in a factory to be described later. It is a function unit that stores a program for generating a map for operating the automatic guided vehicle 35 at the time of operation. The automatic operation program and the map generation program are, for example, input from the input / output unit provided on the operation panel 37 and stored in the operation program storage unit 41.

[0 0 3 9] In addition, this automatic driving program includes a command code regarding the moving position, moving speed, and orientation of the automatic guided vehicle 35 as a target position for the automatic guided vehicle 35 to move. Includes a command code for the operation of the robot 2 5 in sequence and a command code for the operation of the camera 31. In addition, the map generation program includes a command code for running the automatic guided vehicle 35 without a track throughout the factory so that the map information generation unit 48 can generate map information.

[0 0 4 0] The map information storage unit 4 4 stores map information including arrangement information of machines, equipment, devices, etc. (devices, etc.) arranged in the factory where the automatic guided vehicle 35 runs. It is a functional unit, and this map information is generated by the map information generation unit 48.

The map information generation unit 4 8 generates a map stored in the operation program storage unit 4 1 under the control of the automatic operation control unit 4 7 of the control device 40, which will be described in detail later. When the automatic guided vehicle 35 is driven according to the product for use, the spatial information in the factory is acquired from the distance data detected by the sensor, and the plane shape of the equipment installed in the factory is recognized. , For example, the position of a specific device arranged in the factory based on the plan shape of the device registered in advance, in this example, the machine tool 10 and the material stocker 20 and the product stocker 2 1. , Plane shape, etc. (arrangement information) is recognized. Then, the map information generation unit 4 8 stores the obtained spatial information and the arrangement information of the devices and the like in the map information storage unit 4 4 as map information in the factory.

[0 0 4 2] The position recognition unit 4 9 is an automatic guided vehicle in the factory based on the distance data detected by the sensor and the map information in the factory stored in the map information storage unit 4 4. It is a functional unit that recognizes the position of the vehicle 3 5, and based on the position of the automatic guided vehicle 3 5 recognized by this position recognition unit 4 9, the operation of the automatic guided vehicle 3 5 is the automatic operation control unit 4 7 Is controlled by.

[0 0 4 3] The moving position storage unit 4 2 is a moving position as a specific target position for the automatic guided vehicle 3 5 to move, and is a specific moving position corresponding to a command code in the operation program. It is a functional unit that memorizes the moving position, and this moving position includes each working position set for the machine tool 10, the material stocker 20 and the product stocker 2 1 described above. For example, this movement position is determined after the unmanned vehicle 35 is manually operated by the operation panel 37 under the control of the manual operation control unit 46 and moved to each target position. , The position data recognized by the position recognition unit 4 9 is set by the operation of storing the position data in the movement position storage unit 4 2. This operation is a so-called teaching operation.

[0 0 4 4] The operation posture storage unit 4 3 is a posture (operation posture) of the robot 2 5 that changes sequentially when the robot 2 5 operates in a predetermined order, and is the operation program. Command code inside \\ 0 2021/048579 卩 (: 17132019/001004 This is a functional unit that stores data related to the operating posture corresponding to the mode. The data related to this operating posture is under the control of the manual operation control unit 46. Each joint (motor) of the robot 2 5 in each posture when the robot 2 5 is manually operated by the teaching operation using the operation panel 3 7 to take each target posture. This is the rotation angle data of the above, and this rotation angle data is stored in the operation posture storage unit 4 3 as data related to the operation posture.

[0 0 4 5] The specific operating posture of the robot 2 5 is set in the material stocker 2 0 machine tool 10 and the product stocker 2 1, respectively. For example, in the material stocker 20, the work start posture (take-out start posture) when the work is started in the material stocker 20 and the unprocessed work stored in the material stocker 20 are handed 2 9 Each work posture (each take-out posture) for grasping and taking out from the material stocker 20 and the posture when the take-out is completed (the take-out complete posture, which is the same as the take-out start posture in this example). Is set as the take-out operation posture.

[0 0 4 6] In addition, in the machine tool 10 the machine tool has been machined.

The work taking-out operation posture for removing the work from the machine tool 10 and the work mounting operation posture for attaching the pre-machined work to the machine tool 10 are set.

[0 0 4 7] Specifically, in the work taking-out operation posture, for example, the work start posture before entering the machine machine 10, the hand 2 9 and the camera 3 1 enter the machining area of the machine machine 10 Then, the camera 3 1 is made to face the identification figure provided on the support bar 15 and the identification figure is imaged by the camera 3 1 (imaging posture) (see Fig. 4), and the chuck of the machine tool 10 The machined work gripped by the chuck 1 2 is held by the chuck 1 2 by moving the hand 2 9 to the chuck 1 2 side in the posture in which the hand 2 9 is opposed to the machined work gripped by 1 2 (preparation posture for taking out). The posture of gripping the workpiece with the hand 2 9 (holding posture), the posture of separating the hand 2 9 from the chuck 1 2 and removing the processed work \\'from the chuck 1 2 (removal posture), the hand 2 9 And each posture of the posture (work completion posture) in which the camera 3 1 is pulled out from the production machine 10 is set. The posture of the camera 3 1 when the camera 3 1 is made to face the horizontal identification figure is a posture in which the lens and the identification figure are substantially parallel to each other.

[0 0 4 8] In the work mounting operation posture, for example, the work start posture before entering the machine tool 10, the hand 2 9 and the camera 3 1 are made to enter the machining area of the machine tool 10. The posture (imaging posture) (see Fig. 4) in which the camera 3 1 faces the identification figure installed on the support bar 1 5 and the identification figure is imaged by the camera 3 1, and the chuck 1 2 of the machine tool 10 On the other hand, the posture in which the pre-machine tool gripped by the hand 2 9 faces each other (preparation posture), and the posture in which the hand 2 9 is moved to the chuck 1 2 side so that the pre-machine tool can be gripped by the chuck 1 2. (Mounting posture), Hand 2 9 separated from chuck 1 2 (Separation posture), Hand 2 9 and Camera 3 1 pulled out of machine tool 10 (Work completion posture) Set.

[0 0 4 9] In the product stocker 2 1, the work start posture (storage start posture) when the work is started in the product stocker 2 1 and the processed work gripped by the hand 2 9 are held in the product stocker 2 1. Each work posture for storing in 1 (storage posture) and the posture when storage is completed (the storage completion posture, which is the same as the storage start posture in this example) are set as the storage operation postures.

[0 0 5 0] The automatic driving control unit 4 7 uses either the automatic driving program or the map generation program stored in the operation program storage unit 41, and the automatic guided vehicle 3 5 according to the program. It is a functional part that operates the robot 2 5 and the camera 3 1. At that time, the data stored in the moving position storage unit 4 2 and the operating posture storage unit 4 3 are used as necessary.

[0 0 5 1] In the reference image storage unit 4 5, the automatic guided vehicle 3 5 is in the working position set with respect to the machine tool 10 and the robot 2 5 is in the imaging posture during the teaching operation. Sometimes said two This is a functional unit that stores an image obtained by capturing an identification figure provided on the support bar 1 5 of the Lupresetter 1 3 with the camera 3 1 as a reference image.

[0 0 5 2] The correction amount calculation unit 50 is controlled by the automatic operation control unit 47, and the robot 2 5 is in accordance with the automatic operation program stored in the operation program storage unit 41. When the robot 2 5 is in the imaging posture and the identification figure is imaged by the camera 31 when the robot is automatically operated, the image of the current identification figure obtained during the automatic operation and the reference figure are obtained. Based on the reference image (image captured during the teaching operation) stored in the image storage unit 4 5, the amount of positional error of the camera 3 1 between the current posture of the robot 2 5 and the posture during the teaching operation. Estimate the amount of positional error of the camera 3 1 in the biaxial directions orthogonal to each other set in the plane parallel to the identification figure, and the amount of rotation error of the camera 3 1 around the vertical axis orthogonal to the plane. Then, based on each estimated error amount, the correction amount for the working part in the working posture is calculated.

[0 0 5 3] Fig. 6 shows an image of the identification figure captured by the camera 31 during the teaching operation, that is, the reference image. In the figure, the rectangular line shown by the solid line is the field of view of the camera 31, in other words, the outline of the reference image. In addition, Fig. 7 shows the image of the current identification figure obtained during automatic operation with a solid line. In FIG. 7, the rectangular line shown by the solid line is the outline of the current image, and the rectangular line shown by the alternate long and short dash line is the outline of the reference image. Figure 7 shows that there is a discrepancy between the reference image and the current image due to the discrepancy between the imaging posture during the teaching operation of Robot 25 and the current imaging posture. ing.

[0 0 5 4] The correction amount calculation unit 50 first sets by analyzing the reference image shown in FIG. 6, for example, from this reference image, in other words, the identification figure on the frame of the camera 31. Based on the graphic coordinate system (axis 17 axis coordinate system), the preset graphic coordinate system (x _t axis 1 y _t axis coordinate system) and robot coordinate system (X axis 1 y axis coordinate system) _{According to the conversion formula between, the position (X teach} , y teach, r Z _t ea = h) of the camera 3 1 at the time of teaching in the robot coordinate system (X-axis 1-y-axis coordinate system) is calculated. The X-axis and y-axis are two axes that are parallel to the identification figure and are directly intersecting with each other, and are the coordinate system of robot 25 during the teaching operation. Rz is orthogonal to the X-axis and y-axis. The rotation angle of the camera 3 1 around the z-axis. In this example, the x _t axis, y _t axis, X axis, and y axis are set in the horizontal plane (the same applies to the X'axis and y'axis described later).

Next, the correction amount calculation unit 50 analyzes the current image in the same manner, and the graphic coordinate system set from the identification graphic on the frame of the camera 3 1 ( ₁ axis 1 7 _1). Based on the axis coordinate system), according to the above conversion formula, the current position of the camera 3 1 in the coordinate system of Robot 2 5 (X-axis 1 y-axis coordinate system) during the teaching operation (x _curr , y _{cur r} , rz _{cur r} ) is calculated.

[0 0 5 6] Then, the correction amount calculation unit 50 has a position error amount AX, Ay and a position error between the position at the time of teaching operation of the camera 31 in the X-axis 1-y-axis coordinate system and the current position. Estimate the amount of rotation error Arz by the following formula 1 — formula 3. The rotation angle r z around the z-axis can be obtained by extracting two appropriate points with a predetermined distance from the image and calculating the angle with respect to the coordinate axes.

(Formula

△ X ^ c

(Formula

△ — ノ c

(Formula

Arz = T

[0

\\ 0 2021/048579 卩 (: 17132019/001004 Here, as shown in Fig. 7, the coordinate system of the current Robot 25 is the X'axis 1'axis coordinate system, and as shown in Fig. 8, teaching Considering that there is a translational error of X, _{17 between the X-} axis uni-axis coordinate system, which is the coordinate system of Robot 2 5 of the time, the current camera 3 in the X'axis 1 7'-axis coordinate system. The position of 1 (X', ₇ ') is calculated by the following formula 4. Note that X and 7 in the following formula are the positions of the camera 3 1 during teaching in the X-axis and 7-axis coordinate systems, respectively ( _{6). 3} = _¾ , which is known as the default value.

(Formula 4)

_{Then, the translation error 1 X} , is calculated by the following formula 5 which is a modification of the above formula 4.

The correction amount calculation unit 50 calculates the translation error amount I _X , according to this mathematical formula 5, and calculates the translation error amount _X , ₁₇ and the rotation error amount △ ^ ₂ as described above. The amount of correction in the working posture.

(Formula 5) _{X'005 / ^ å —} sίnArz ^ X + Ax y ^{^} _{sinArz (} : 〇! + However, the current position of the camera 3 1 in the X'axis 1 7'axis coordinate system (X', 7') Is the same as the current position of the camera 3 1 in the X-axis 17-axis coordinate system (X 10 △ X, 7 ㎶ 7).

Is.

[0 0 5 9] Then, the automatic operation control unit 47 is in a working posture when the robot 25 works on the machine tool 10, for example, the taking-out preparation posture, the gripping posture, and the work-taking posture in the work taking-out operation posture. Regarding the removal posture, the mounting preparation posture, the mounting posture, and the separation posture in the work mounting operation posture, the hand 2 9 of the robot 2 5 is based on the correction amount calculated by the correction amount calculation unit 50. Correct the position.

[0 0 6 0] For example, when positioning the hand 2 9 of the robot 2 5 with respect to the chuck 1 2, the hand in the X'axis 1'axis coordinate system, which is the current coordinate system of the robot 2 5. The positioning position of the hand 2 9 in the X'axis 1 7'axis coordinate system so that the positioning position of 2 9 matches the positioning position of the hand 2 9 in the X axis 17 axis coordinate system set during the teaching operation. Is corrected.

[0 0 6 1] The mode of this correction is shown in FIG. In Figure 9, position and position X. ， ，. Is the set position of hand 2 9 in the X-axis uniaxial coordinate system, which is the robot coordinate system during the teaching operation, and hand 2 9 is set for chuck 1 2 from the position X? In the imaging posture. Position X. ， V?. It is set to be positioned at. If there is no misalignment between the automatic guided vehicle 3 5 and the robot 2 5 positioned at the work position described above, c.

In FIG. 9, the position X ″ ₅ is the position of the hand 2 9 in the imaging posture in the X'axis uniaxial coordinate system, which is the robot coordinate system at the time of the current operation. These positions'and 7'are positioned with respect to _{the positions X 5} ) and ₅ ) during the teaching operation because the automatic guided vehicles 35 and robots 25 positioned at the above working positions are misaligned. An error 厶, 厶 7, and a rotation error 厶 ^ ₂ have occurred, and in the X'axis 1 7'axis coordinate system, the above X 7! > Corresponds to the position. Then, in this X'axis one'axis coordinate system, the above. ， ，. The position corresponding to is X'. ，'. However, this position is deviated from the true position of chuck 1 2. Therefore, the automatic operation control unit 4 7 is this'. ， ₇ ' \\ 0 2021/048579 卩 (: 17132019/001004

= Was corrected according to the following formula 6 based _{on the translational error amount 1 X} , which was calculated by the correction amount calculation unit 50. ，! !! '. Is calculated and this corrected position X 11'. ， 11'. While moving the hand 2 9 to, the rotation posture of the hand 2 9 around the axis is corrected based on the rotation error amount Δr 2.

(Formula 6)

This position data X 11'. ， VV h. Is converted into the angle data of each joint of the robot 25 by a preset conversion formula, and the robot 25 is controlled according to the converted angle data.

[0 0 6 4] Then, the supplement 1 ₁ , V ph _{1 corresponding to each position X 1} , V? ₁ of the hand 2 9 set in each working posture in which the robot 2 5 works on the machine tool 10 Is a generalization of the above formula 8, and the automatic operation control unit 4 7 corrects the axial posture based on the rotation error amount △ r 2, and is calculated in this way. Correction position X

Move Hand 2 9 to. However, 1 is a natural number greater than or equal to 1.

(Formula 9)

According to the system 1 of this example having the above configuration, unmanned automatic production is carried out as follows.

That is, under the control of the automatic operation control unit 47 of the control device 40, the automatic operation program stored in the operation program storage unit 41 is executed, and this automatic operation program is executed. Therefore, for example, the automatic guided vehicle 35 and the robot 25 operate as follows.

[0 0 6 7] First, the automatic guided vehicle 3 5 moves to the work position set for the machine tool 10 and the robot 2 5 takes the work start posture of the work take-out operation described above. At this time, the machine tool 10 has completed the predetermined machining, and the door cover has been opened so that the robot 25 can enter the machining area, and the automatic operation control unit 47 Upon receiving the command, it is assumed that the support bar 15 of the tool preset evening 13 is advanced into the machining area.

Next, the robot 25 shifts to the imaging posture, and the identification diagram provided on the support bar 15 is imaged by the camera 31. Then, when the identification figure is imaged by the camera 31 in this way, the correction amount calculation unit 50 displays the image of the identification figure and the reference image stored in the reference image storage unit 45. Based on the image, according to the above formulas 1-3, the robot 2 5 \\ 0 2021/048579 卩 (: 17132019/001004 The amount of position error between the imaging posture during the eating operation and the current imaging posture △ X and the rotation error amount ₂ are estimated, and each estimated error amount Based on the above formula 4-15, the amount of correction for _{robot 2 5 1 7 and rotation error}

[0 0 6 9] Then, based on each correction amount calculated by the correction amount calculation unit 50, the automatic operation control unit 47 performs the subsequent work take-out operation posture, that is, the above-mentioned take-out preparation posture and gripping posture. , The position of the hand 2 9 in the removal posture and the work completion posture is corrected according to Equation 9, and the rotation position around the axis is corrected, and the machined workpiece gripped by the chuck 1 2 of the machine tool 10 is c. Grip it to the machine tool 2 9 and take it out from the machine tool 10. After the robot 25 is made to take the gripping posture, the chuck 1 2 is opened by transmitting a chuck opening command from the automatic operation control unit 47 to the machine tool 10.

Next, the automatic operation control unit 4 7 moves the automatic guided vehicle 3 5 to the working position set for the product stocker 2 1 and at the robot 25 for the product. The storage start posture when starting work in the stocker 2 1, each storage posture for storing the processed work gripped in the hand 2 9 in the product stocker 2 1 and the storage completion posture when the storage is completed. Take them in sequence and store the processed workpieces gripped by the hand 2 9 in the product stocker 2 1.

[0 0 7 1] Next, the automatic operation control unit 4 7 moves the automatic guided vehicle 3 5 to the working position set for the material stocker 2 0, and at the robot 25 the material concerned. The take-out start posture when starting work on the stocker 20 and the work to be taken out from the material stocker 20 by grasping the unprocessed work stored in the material stocker 20 with the hand 2 9. The take-out posture and the take-out completion posture when the take-out is completed are sequentially taken, and the hand 29 is made to grip the work before machining.

Next, the automatic operation control unit 4 7 again moves the automatic guided vehicle 3 5 to the working position set for the machine tool 10 and the work described above in the robot 25. Get ready to start the installation operation. Then, the robot 25 is moved to the imaging posture, and the identification figure provided on the support bar 15 is imaged by the camera 31. Then, when the identification figure is imaged by the camera 31 in this way, the correction amount calculation unit 50 displays the image of the identification figure and the reference image stored in the reference image storage unit 45. Based on the above equations 1 to 3, the amount of positional error between the imaging posture during the teaching operation of Robot 2 5 and the current imaging posture, △ _7, and the amount of rotation error △ ^ 2 are estimated and estimated. Based on each of the error amounts, the translational error _{correction amounts 1, 17} and the rotation error correction amount △ ^ ₂ for the subsequent workpiece mounting motion posture of Robot 25 are calculated according to the above-mentioned formulas 4-15. Will be done.

[0 0 7 3] After that, the automatic operation control unit 4 7 uses the correction amount calculated by the correction amount calculation unit 50 to obtain the subsequent work mounting operation postures of the robot 25, that is, described above. The position of the hand 2 9 in the mounting preparation posture, the mounting posture, the separation posture, and the work completion posture is corrected according to Equation 9, and the rotation position around the axis is corrected, and the robot 25 is gripped by the hand 2 9. After attaching the pre-machining work to the chuck 1 2 of the machine tool 10 and then letting it move out of the machine. After that, the automatic operation control unit 47 sends a machining start command to the machine tool 10 to cause the machine tool 10 to perform the machining operation. After the robot 2 5 is made to take the mounting posture, the automatic operation control unit 47 sends a chuck closing command to the machine tool 10 to close the chuck 1 2 and the chuck 1 2 The work before machining is gripped by.

By repeating the above, unmanned automatic production is continuously executed in the system 1 of this example.

[0 0 7 5] \\ 0 2021/048579 卩 (: 17132019/001004 And in system 1 of this example, the robot 2 5 uses the identification figure placed in the processing area of the machine tool 10 that the robot actually works on. Since the working posture of 25 is corrected, the working posture can be corrected accurately, and as a result, Robot 25 can perform the work accurately even in the work that requires high motion accuracy. Can be executed.

[0 0 7 6] In this way, the robot 2 5 performs accurate work, so that the system 1 operates at a high operating rate without causing unnecessary interruption, and as a result, the system 1 According to the report, it is possible to achieve unmanned operation with high reliability and high production efficiency.

[0 0 7 7] In addition, the robot 2 5 that operates according to the operation program is configured to execute this in one operation when the identification figure is imaged by the camera 3 1, so that it is compared with the conventional one. Therefore, accurate correction can be performed in a short time.

[0 0 7 8] In this example, when the machine tool 10 is performing machining, an identification figure is provided on the support bar 1 5 of the tool presetter 1 3 stored outside the machining area. , It is possible to prevent the identification figure from being soiled by chips or the like generated at the time of addition, and as a result, the above correction can be performed with high accuracy.

[0 0 7 9] Further, in this embodiment, the discrimination figure, since a plurality of pixels are assumed to have a Ma Torikusu structure arranged in a two-dimensional, the position error amount △ X, △ ₇ and, The amount of rotation error △ ^ ₂ can be estimated with high accuracy and high repeatability.

Although one embodiment of the present invention has been described above, the specific embodiments that the present invention can take are not limited thereto.

[0 0 8 1] For example, in each of the above-described embodiments, as the identification figure, a figure having a matrix structure in which a plurality of pixels are arranged two-dimensionally is adopted, but the present invention is not limited to this. , Various figures can be used as long as the correction amount of the posture of Robot 25 can be calculated from the captured image.

[0 0 8 2] In the above example, the position error in the X-axis and 7-axis directions and the rotation error around the 2-axis are corrected, but the present invention is not limited to this, and the correction amount calculation unit 5 0 is configured to estimate the amount of position error in the two axial directions and calculate the corresponding correction amount, and the automatic operation control unit 47 is the calculated amount of correction in the axial direction. Based on this, it may be configured to correct the axial position in each working position of Robot 25. The amount of position error in the two-axis direction can be calculated, for example, from the magnification of the basic image size and the current image size.

[0 0 8 3] Further, in the above example, an embodiment using an automatic guided vehicle 35 has been illustrated, but the present invention is not limited to this. It may be a transport device that can be pushed and moved by a person like a general trolley. A robot 25 is mounted on this transfer device, and the transfer device is manually transported to the working position of the machine tool 10 and the machine tool 10 is made to attach / detach the workpiece by the robot 25. It may be an embodiment.

[0 0 8 4] In the above example, a vertical lathe was illustrated as a machine tool, but it is not limited to this, and in addition to horizontal lathes, vertical and horizontal machining centers, tool spindles and workpieces. Any previously known machine tool, such as a multi-tasking machine with a spindle, can be applied.

[0 0 8 5] In the above example, the X-axis and the axes (X'axis and'-axis) are set in the horizontal plane and the two axes are set in the vertical direction in the robot coordinate system. Not limited to this, the direction of the coordinate axes can be set arbitrarily. The same applies to the coordinate axes of the identification figure, XI axes, and axes. \\ 020 21/048579 卩 (: 17132019/001004).

[00 8 6] Again, the description of the embodiments described above is exemplary in all respects and is not restrictive. Modifications and changes can be made as appropriate for those skilled in the art. The scope of the present invention is indicated by the scope of claims, not by the embodiments described above. Further, the scope of the present invention includes modifications from the embodiment within the scope of the claims and within the scope of the claims.

[Explanation of symbols]

[00 8 7]

1 system

1 0 Machine tool 1 1 Spindle

1 2 chuck

1 3 Tool presetter

14 Contact support bar Display board

2 0 Material Stocker 2 1 Product Stocker 2 5 Robo, Soto

2 9 hands

31 camera

35 Automatic guided vehicle

3 7 Operation panel

40 Control unit

41 Operation program storage

42 Moving position storage

43 Motion posture memory

44 Map Information Storage

45 Reference image storage

46 Manual operation control unit

47 Automatic operation control unit

48 Map information generator

49 Position recognition unit

50 Correction amount calculation unit

51 Input / Exit Cainter Face Work before processing ‘Processed work

Claims

\\ 0 2021/048579 卩 (: 171 2019/001004

[Document name] Scope of claim [Claim 1] A machine tool that performs predetermined processing on a workpiece, a camera that captures an image, and an acting part that acts on the workpiece, and the workpiece is According to an operation program including a robot for performing work, a transfer device equipped with the robot and configured to be movable to a work position set for the machine tool, and a preset operation command. The work start posture, the imaging posture in which the camera is made to face the identification figure for posture correction provided in the machine tool, and the imaging posture in which the identification figure is imaged by the camera, and the work. A control device configured to sequentially take one or more working postures for operating the working unit is provided, and the working start posture, the imaging posture, and the working posture are the teaching operations of the robot. This is a preset system, in which the identification figure is formed on a predetermined plane and arranged in the machining area of the machine tool, and the control device is used during the teaching operation. When the robot is moved to the imaging posture, the image of the identification figure captured by the camera is stored in advance as a reference image, and the robot is operated according to the operation program. Based on the image of the identification figure captured by the camera after shifting the robot from the work start posture to the imaging posture and the reference image, the robot is moved to the working position. The amount of error in the position of the camera between the current posture of the camera and the posture during the teaching operation, which is the amount of error in the position of the camera in two axes perpendicular to each other set in a plane parallel to the identification figure. The amount of positional error and the amount of rotation error of the camera around the vertical axis orthogonal to the plane are estimated, and the amount of correction for the working part in the working posture is calculated based on each estimated error amount. , A system configured to correct the position of the working part in the working posture based on the calculated correction amount.

2. The control device uses the two axes as the X-axis and the seven-axis, which are coordinate systems corresponding to the posture of the robot during the teaching operation, and the position of the camera in the seven-axis coordinate system. Estimate the amount of error △ X, ₇ , and the amount of rotation error △ r 2 of the camera around the X-axis and the two axes orthogonal to the X-axis, and based on the estimated amount of position error, ₇ , and the amount of rotation error △ ^ ₂ . Then, in the X-axis uniaxial coordinate system, the translational error amount 1: of the working part between the teaching operation and the present is calculated by the following formula, and the calculated translational error amount 1 and the rotation error. The system according to claim 1, which is configured to correct the position of the working part in each of the working postures based on the quantity _2.

However, in this formula, X and 7 are the positions of the camera during the teaching operation in the X-axis and 17-axis coordinate systems, and X', is the coordinate system corresponding to the current posture of the robot. 'The current position of the camera in the uniaxial coordinate system.

3. The control device is based on the translational error amount and the rotation error amount Δ ^ 2, and is in the X'axis uniaxial coordinate system, which is the coordinate system corresponding to the current posture of the robot. The corrected position X 11 '7 11 ' ₁ of the working part in each working posture is calculated by the following formula, and the corrected position X 11'' ₁ of the working part in each working posture is calculated. The system according to claim 2, wherein the working part is configured to rotate around the two axes so as to determine and compensate for the rotation error amount Δ ^ _2. \\ 0 2021/048579 卩 (: 171 2019/001004

However, in this formula, 1 is a natural number of 1 or more, and X? 1, is the position of the action part in the X-axis 17-axis coordinate system set at the time of the teaching operation.

4. The automatic guided vehicle is an automatic guided vehicle controlled by the control device, and is configured to pass through the working position set for the machine tool under the control of the control device. The system according to claim 1, wherein the system is characterized by being used.

5. The system according to claim 1, wherein the identification figure has a matrix structure in which a plurality of pixels are arranged two-dimensionally.

6. A robot provided in a machine tool for capturing an image including an identification figure and a robot having an acting portion acting on the work are mounted, and the robot can hold the work. In the first position, the transport device for transporting the robot transports the robot to the first position, and then the camera captures an image including the identification figure provided on the machine tool. Then, according to the position information of the identification figure in the image, the second position of the action part on the X-axis and the V-axis in the three-dimensional space of the X-axis, the V-axis, and the axis is linearly moved and rotationally moved. It is a machine tool for machining a work, in which the above-mentioned acting part is made to act on the work inside the machine tool after the correction is made by putting it on the working part and the second position is corrected. Is a machine tool, characterized in that it is located within the machining area of the machine tool.