JP2011048467A - Machining system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inexpensively configure a machining system having a robot. <P>SOLUTION: The machining system having a machine tool 1 to be controlled by a machine tool controller 10 and a robot 2 to be controlled by a robot controller 20 to perform work on the machine tool 1 is provided with: a data acquisition means 20 for acquiring, based on known position relation of a set point P determined at a predetermined movable part of a robot 2 to a robot control point Q, the position data of the set point P on a robot coordinate system; measurement means 10 and 14 for measuring the position of the set point P on the machine tool coordinate system; and a relative relation deriving means 20 for deriving a relative relation between the robot coordinate system and the machine tool coordinate system based on the position data acquired by the data acquisition means 20 and the position data measured by the measurement means 10 and 14. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a machining system having a robot that performs a work operation of a workpiece or a tool on a machine tool.

  On the coordinate system of the machine tool and on the robot coordinate system that performs handling operations, the positions of three or more predetermined measurement points are measured, and the relative relationship between the two coordinate systems is obtained based on the measured values. An apparatus that corrects position data is known (see, for example, Patent Document 1). In the apparatus described in Patent Document 1, three-dimensional positions of three points on a jig attached to a machine tool are measured on a robot coordinate system by an imaging means attached to the tip of a robot arm, and the measured value is obtained. Based on this, the robot position data is corrected.

JP 2005-138223 A

  However, the apparatus described in Patent Document 1 is expensive because the imaging means is attached to the tip of the robot arm.

  The present invention is a machining system having a machine tool controlled by a machine tool control device and a robot controlled by the robot control device and performing work on the machine tool, and is defined as a predetermined movable part of the robot. Based on the known positional relationship of the set point to the robot control point, data acquisition means for acquiring the set point position data on the robot coordinate system determined for the robot, and setting on the machine tool coordinate system determined for the machine tool Based on the measuring means for measuring the position of the point, the position data on the robot coordinate system acquired by the data acquiring means, and the position data on the machine tool coordinate system measured by the measuring means, And a relative relationship deriving unit for deriving the relative relationship of the machine tool coordinate system.

  According to the present invention, since it is not necessary to provide a position detector on the robot side in deriving the relative relationship between the robot coordinate system and the machine tool coordinate system, the machining system can be configured at low cost.

It is a figure showing a schematic structure of a processing system concerning an embodiment of the invention. It is a block diagram showing a schematic structure of a processing system concerning an embodiment of the invention. It is a perspective view which shows roughly the various shapes of a robot hand. It is a figure which shows the position of the measurement point of a robot hand which has A shape nail | claw, and a setting point. It is a figure which shows the position of the measurement point and setting point of a robot hand which has a B-shaped nail | claw. It is a figure which shows the position of the measurement point of a robot hand which has a C-shaped nail | claw, and a setting point. It is a flowchart which shows an example of the process in the machine control controller of FIG. 2, and a robot controller.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing a schematic configuration of a machining system according to the present embodiment.

  This machining system includes a machine tool 1 having a table 11 on which a workpiece W is mounted and a tool post 12 to which a tool T is attached, and an articulated robot 2 in which a hand 22 as an end effector is attached to the tip of an arm 21. And a machine control controller 10 that controls the operation of the machine tool 1 and a robot control controller 20 that controls the operation of the robot 2. The robot 2 operates under the control of the robot controller 20 in accordance with a predetermined work program created in advance, and supplies processing-related objects such as the workpiece W and the tool T to the mounting unit such as the table 11 and the tool post 12. Or handling work to remove from the mounting part.

  In such a machining system, the position data of the workpiece W and the tool T operating on the mounting portion of the machine tool 1 is, for example, the orthogonal coordinate system using the feed axis of the table 11 or the tool post 12 as a coordinate axis. It is given with reference to the coordinate system (machine tool coordinate system). On the other hand, the position data of the robot itself during the handling operation of the robot 2 is given with reference to the coordinate system (robot coordinate system) of the robot 2 such as the world coordinate system. Therefore, in order for the robot 2 to perform the handling operation with respect to the machine tool 1 with high accuracy, a relative relationship between the machine tool coordinate system and the robot coordinate system is obtained in advance, and position data of the machine tool coordinate system is obtained using the relative relationship. Must be accurately converted to position data in the robot coordinate system. The position data is data including the position and orientation.

  The relative relationship between the machine tool coordinate system and the robot coordinate system can be obtained, for example, as follows. That is, the position measuring device provided on the machine tool 1 is used to measure the positions of three different points on the machine tool coordinate system, and the position measuring device provided on the robot 2 is used to measure the position on the robot coordinate system. Then, the same three positions are measured. Using the measurement data on the machine tool coordinate system and the robot coordinate system, a coordinate transformation matrix for coordinate transformation from the robot coordinate system to the machine tool coordinate system is obtained. Represents a relationship.

  However, if the machine tool 1 and the robot 2 are each provided with a position measuring device as described above, and each position measuring device performs position measurement on the machine tool coordinate system and the robot coordinate system, the system configuration is as follows. It becomes expensive. Therefore, in the present embodiment, as described below, the positional relationship with respect to the control reference point (robot control point) of the robot 2 is not provided by the position measuring device provided in the machine tool 1 without providing the position measuring device in the robot 2. Measure the position of the set point for which is known.

  FIG. 2 is a block diagram showing a schematic configuration of the machining system according to the present embodiment. The machine controller 10 includes an arithmetic processing unit having a CPU, ROM, RAM, communication device, and other peripheral circuits. Similarly, the robot controller 20 includes an arithmetic processing unit having a CPU, a ROM, a RAM, a communication device, and other peripheral circuits. The machine control controller 10 and the robot control controller 20 are connected via an internal communication device and an external cable 31, and communication is performed between the machine control controller 10 and the robot control controller 20 as described later.

  The machine controller 10 and the robot controller 20 are connected to the machine controller 1 via the input device 30 including, for example, a keyboard, a touch panel, and various switches. Etc. are input. Various information can also be input from the input device 30 via a storage medium storing programs and various data.

  Although not shown, the machine control controller 10 processes a signal from the machine tool controller that controls the drive of the table 11 (work W) and the tool post 12 (tool T), and the measuring instrument 14 in a measurement mode that will be described later. And a signal processing unit. The machine tool control unit outputs a control signal to an actuator 13 provided in the machine tool 1 to control the position and orientation of the workpiece W and the tool T on the machine tool, the driving of the tool T, and the like.

  Although not shown, the robot controller 20 calculates a relative relationship between the machine tool coordinate system and the robot coordinate system, and based on this relative relationship, creates a work program for the robot 2, and the work program. And a robot control unit that outputs a control signal to the actuator 23 for driving the robot and controls the operation of the robot 2 during handling work.

  The measuring instrument 14 is configured, for example, by attaching a probe to the tool mounting portion of the tool post 12 instead of the tool T, and a pressing switch that outputs an ON signal when the tip of the probe is pressed against the object to be measured. And a position detector for detecting the three-dimensional position of the object to be measured in the machine tool coordinate system.

  In the present embodiment, the positions of a plurality of arbitrary points on the surface of the hand 22 attached to the tip of the robot arm are measured by the measuring instrument 14 as will be described later, and on the predetermined hand based on the measured values. Find the position of the set point on the machine tool coordinate system. The position measurement procedure in this case varies depending on the shape of the hand 22. FIG. 3 is a perspective view schematically showing various shapes of the hand 22, and the shapes of FIGS. 3A to 3C are referred to as A shape, B shape, and C shape, respectively.

  The A shape shown in FIG. 3A has two substantially rectangular parallelepiped claws 22a that can be expanded and contracted at the tip of the hand, and the workpiece W is gripped by these claws 22a. The B shape shown in FIG. 3B has three substantially rectangular parallelepiped-shaped claws 22a that can be expanded and contracted at the tip of the hand at intervals of 120 °, and the work W is gripped by these claws 22a. The C shape shown in FIG. 3C has three substantially cylindrical claws 22b that can be expanded and contracted at the tip of the hand at intervals of 120 °, and the workpiece W is gripped by these claws 22b.

  3A to 3C, a point P at the tip of the hand is a set point for obtaining position data on the machine tool coordinate system, and is given as position data in the robot coordinate system. Further, the point Q is a control reference point to be controlled during robot control, and is given as position data in the robot coordinate system. In the figure, the control point Q is set as the center point of the tip of the robot hand, but the position of the control point Q can be arbitrarily set by the operator, and the control point Q can be matched with the set point P.

  As shown in FIG. 3, when the control point Q is set at the center point of the tip of the robot hand, the positional relationship (distance, etc.) in the robot coordinate system between the control point Q and the predetermined point P is a design value or an actual measurement value. It can be set in the robot controller 20 in advance. Thereby, the position data of the control point Q and the position data of the set point P on the robot coordinate system become known data. By determining the set point P on the robot hand whose positional relationship with the control point Q is known, when the robot 2 is moved, the position data of the set point P on the robot coordinate system without using a position detector. Can be requested.

Main operations of the machining system according to the present embodiment will be described. In the following, a method for deriving a relative relationship for each shape of the robot hand 22 in the machine tool coordinate system and the robot coordinate system will be mainly described.
(1) A shape FIG. 4A is a perspective view showing an A-shaped hand tip, and FIG. 4B is an enlarged view of the claw 22a of FIG. 4A. Here, the set point P is indicated by Pa. The set point Pa is set at a point where three adjacent surfaces S1 to S3 of the rectangular parallelepiped forming the claw 22a intersect, that is, a tip corner of the claw 22a.

  First, the operator attaches the probe to the tool attachment portion of the tool post 12 and changes the operation mode of the robot 2 from the work mode to the measurement mode by operating the input device 30 (for example, operating a mode selection switch). The work mode is a mode for handling work, and the measurement mode is a mode for obtaining position data of the set point P. When the power is turned on, the operation mode is set to the work mode.

Next, in a state where the robot hand 22 is fixed to the first position and posture, the operator operates the tool mounting portion of the tool post 12, and moves the probe of the measuring instrument 14 to any three measurement points P1 to P1 on the surface S1. Press against P3. Based on the signal from the measuring instrument 14 at this time, the machine controller 10 causes the position data P1 (x1, y1, z1) and P2 (x2) of the measurement points P1 to P3 on the machine tool coordinate system (for example, xyz coordinate system). , Y2, z2), P3 (x3, y3, z3), and the following plane formula (I) of the surface S1 is calculated from these position data.
A1.x + B1.y + C1.z = D1 (I)

Similarly, the probe of the measuring instrument 14 is pressed to arbitrary measurement points P4 to P6 on the surface S2, thereby acquiring the position data of the points P4 to P6, and the following plane formula (II) of the surface S2 is obtained. calculate.
A2 ・ x + B2 ・ y + C2 ・ z = D2 (II)
Further, the probe of the measuring instrument 14 is pressed against arbitrary measurement points P7 to P9 on the surface S3, thereby acquiring the position data of the points P7 to P9, and the following plane formula (III) of the surface S3 is calculated. To do.
A3 ・ x + B3 ・ y + C3 ・ z = D3 (III)
In the above formulas (I) to (III), A1 to A3, B1 to B3, C1 to C3, D1 to D4 are constants. The machine controller 10 calculates position data (xa, ya, za) of the set point Pa by solving these equations (I) to (III) simultaneously.

  Next, the operator operates the robot hand 22 to a second position and posture different from the first position and posture, and fixes the robot hand 22 to the second position and posture in the same manner as described above. Then, the positions of arbitrary measurement points P1 to P9 on the surfaces S1 to S3 are measured, and the position data of the set point Pa is calculated based on these measurement values. Further, the robot hand 22 is operated to the third position and posture different from the first position, posture and second position and posture, and the robot hand 22 is fixed to the third position and posture as described above. In the same manner as above, the positions of arbitrary measurement points P1 to P9 on the surfaces S1 to S3 are measured, and the position data of the set point Pa is calculated based on these measurement values.

  As a result, position data of the set point Pa in the first position, posture to third position, and posture, that is, three position data of the set point Pa in the machine tool coordinate system is obtained. The machine controller 10 transmits these position data to the robot controller 20 via the cable 31. The robot controller 20 has the first position, the posture to the third position, the position data of the robot control point Q in the posture, and the positional relationship on the robot coordinate system between the predetermined set point Pa and the control point Q. Based on this, three position data of the set point Pa in the robot coordinate system are obtained.

After determining the three position data of the set point Pa on the machine tool coordinate system and the three position data of the set point Pa on the robot coordinate system in this way, the robot controller 20 may, for example, ) To obtain a coordinate transformation matrix Ta from the robot coordinate system to the machine tool coordinate system that satisfies the relationship (1).
Tm = Ta ・ Tr (IV)
Here, Tr is a matrix representing the position and orientation in the robot coordinate system, and Tm is a matrix representing the position and orientation in the machine tool coordinate system.

  This conversion matrix Ta represents the relative relationship between the machine tool coordinate system and the robot coordinate system. Since this type of determinant calculation is well known, description of the conversion matrix Ta calculation is omitted. The robot controller 20 creates a work program for the robot 2 using this conversion matrix Ta, and controls the operation of the robot 2 during handling work based on this work program. If the work program is created in advance offline or the like, the position data of the work program is corrected using the conversion matrix Ta, and the operation of the robot 2 during the handling work is controlled based on the corrected program.

(2) B shape FIG. 5A is a perspective view showing a B-shaped hand tip, and FIG. 5B is an enlarged view of the claw 22a of FIG. 5A. Here, the set point P is indicated by Pb. Similarly to the shape A, the set point Pb is set at a point where three adjacent surfaces S1 to S3 of the rectangular parallelepiped forming the claw 22a intersect, that is, at the corner of the tip of the claw 22a.

  The relative relationship between the machine tool coordinate system and the robot coordinate system is derived in the same manner as in the case of the A shape. That is, the operator presses the probe of the measuring instrument 14 against arbitrary measurement points P1 to P9 on the surfaces S1 to S3 with the robot hand 22 fixed at the first position and posture. Thereby, the machine controller 10 acquires the position data of the measurement points P1 to P9 in the machine tool coordinate system, calculates the plane expressions (I) to (III) of the surfaces S1 to S3 based on these position data, and these planes The position data of the set point Pb is calculated by solving the equations (I) to (III) simultaneously.

  Next, the robot hand 22 is operated to the second position and posture, and the positions of arbitrary measurement points P1 to P9 on the surfaces S1 to S3 are measured with the robot hand 22 fixed to the second position and posture. . Furthermore, the robot hand 22 is operated to the third position and posture, and the positions of arbitrary measurement points P1 to P9 on the surfaces S1 to S3 are measured in a state where the robot hand 22 is fixed to the third position and posture. Based on these measured values, the machine controller 10 calculates three position data of the set point Pb in the machine tool coordinate system, and transmits the calculated three position data to the robot controller 20.

  Based on the first position, the posture to the third position, the position data of the robot control point Q in the posture, and the positional relationship between the set point Pb of the robot coordinate system and the control point Q, the robot controller 20 The three position data of the set point Pb on the robot coordinate system in the posture to the third position and posture are obtained. After obtaining the three position data of the set point Pb on the machine tool coordinate system and the three position data of the set point Pb on the robot coordinate system in this way, the coordinate transformation matrix Ta is obtained as described above. Thus, the relative relationship between the machine tool coordinate system and the robot coordinate system is derived.

(3) C shape FIG. 6A is a perspective view showing a C-shaped hand tip, and FIG. 6B is an enlarged view of the claw 22b of FIG. 6A. Here, the set point P is indicated by Pc. The set point Pc is set at the center point of the circular upper end surface S1 of the cylinder forming the claw 22b.

First, the operator presses the probe of the measuring instrument 14 against arbitrary measurement points P1 to P3 on the surface S1 with the robot hand 22 fixed at the first position and posture. Thereby, the machine controller 10 acquires the position data of the measurement points P1 to P3 on the machine tool coordinate system, and calculates the following plane formula (V) of the surface S1 from these position data.
A1 · x + B1 · y + C1 · z = D1 (V)
A1, B1, C1, and D1 are constants.

Further, the probe is pressed against an arbitrary point P4 on the cylindrical side surface S2, and the position of the point P4 is measured, and the position data at this time is used to pass the point P4 on the cylindrical side surface S2 perpendicular to the surface S1. A linear equation (VI) such as
x / A1 = (y / B1) + B2 = (z / C1) + C2 (VI)
A1, B1, B2, C1, and C2 are constants. The machine controller 10 calculates the position P7 (x1, y1, z1) of the intersection P7 between the straight line and the plane S1 by solving the linear expression (VI) and the planar expression (V) simultaneously.

  Similarly, the probe of the measuring instrument 14 is pressed against arbitrary measurement points P5 and P6 on the surface S2, respectively, to acquire position data of the points P5 and P6. As a result, a straight line equation perpendicular to the surface S1 and passing through the point P5 and a straight line equation perpendicular to the surface S1 and passing through the point P6 are calculated, and positions P8 of intersections P8 and P9 between these straight lines and the plane S1 are calculated. (X2, y2, z2) and P9 (x3, y3, z3) are calculated, respectively.

Here, assuming that the center position of the circle is Pc (xc, yc, zc) and the radius is R, the following equations (VII), (VIII), and (IX) hold respectively.
^{(X1-xc) 2 + (} y1-yc) 2 + (z1-zc) 2 = r 2 (VII)
^{(X2-xc) 2 + (} y2-yc) 2 + (z2-zc) 2 = r 2 (VIII)
(X3-xc) ² + (y3-yc) ² + (z3-zc) ² = r ² (IX)
Further, when (xc, yc, zc) is substituted into the plane formula (V), the following formula (X) is obtained.
A1.xc + B1.yc + C1.zc = D1 (X)
The machine controller 10 calculates the position data of the set point Pc by solving the above equations (VII), (VIII), (IX), and (X) simultaneously.

  Next, after the robot hand 22 is operated to the second position and posture different from the first position and posture, the position and posture of the robot hand 22 are fixed, and the surface on the surface S1 is the same as described above. The positions of arbitrary measurement points P1 to P3 and arbitrary measurement points P4 to P6 on the surface S2 are measured, and position data of the set point Pc is calculated. Further, after the robot hand 22 is operated to the third position and posture different from the first position, posture, and second position and posture, the position and posture of the robot hand 22 are fixed as described above. Similarly, the positions of arbitrary measurement points P1 to P3 on the surface S1 and arbitrary measurement points P4 to P6 on the surface S2 are measured, and the position data of the set point Pc is calculated.

  Thereby, the machine controller 10 acquires the position data of the set point Pc in the first position, the posture to the third position, and the posture, that is, the three position data of the set point Pa in the machine tool coordinate system. Data is transmitted to the robot controller 20. The robot controller 20 is based on the first position, the posture to the third position, the position data of the robot control point Q in the posture, and the positional relationship between the set point Pc and the control point Q on the robot coordinate system. Three position data of the set point Pc at is calculated.

  After obtaining the three position data of the set point Pc on the machine tool coordinate system and the three position data of the set point Pc on the robot coordinate system in this way, the coordinate transformation matrix Ta is obtained as described above. Thus, the relative relationship between the machine tool coordinate system and the robot coordinate system is derived.

  The operations in the machine controller 10 and the robot controller 20 will be described more specifically. Hereinafter, a case where the robot hand 22 has an A shape will be described. FIG. 7 is a flowchart illustrating an example of processing executed by the CPUs of the machine controller 10 and the robot controller 20. The processing shown in this flowchart is started when the machine controller 10 and the robot controller 20 are turned on, for example.

  First, the process of the machine controller 10 will be described. In step S11, it is determined whether or not the operation mode of the robot 2 has been changed from the work mode to the measurement mode based on a signal from the input device 30 (mode changeover switch). If step S11 is affirmed, the process proceeds to step S12, and a signal is output to the robot controller 20 via the cable 31 to notify the change to the measurement mode. In step S <b> 13, whether or not the probe has been pressed against the measurement points P <b> 1 to P <b> 9 of the robot hand 22 as a result of the operator operating the tool mounting portion of the tool post 12, that is, whether or not an on signal is output from the measuring instrument 14. Determine.

  When step S13 is affirmed, the process proceeds to step S14, and the position data on the machine tool coordinate system detected by the measuring instrument 14 is stored in the memory of the machine control controller 10. In step S15, it is determined whether or not the position data of all measurement points P1 to P9 has been acquired, that is, whether or not acquisition of necessary data has been completed. If step S15 is negative, the process proceeds to step 13 and the same process is repeated until the acquisition of necessary data is completed.

  If step S15 is affirmed, the process proceeds to step S16, and the signal processing unit calculates the position of the set point P as described above using the position data of the measurement points P1 to P9. In other words, the plane equations (I) to (III) of the surfaces S1 to S3 are calculated from the position data of the measurement points P1 to P3, P4 to P6, and P7 to P9, respectively. The position data of the set point P at is obtained. In step S17, the position data of the set point P is transmitted to the robot controller 20 via the cable 31.

  In step S18, it is determined whether or not the end of the measurement mode has been commanded by an operation of the input device 30, for example, an operation of a mode switch. The end of the measurement mode is instructed after the operator operates the robot hand 22 from the first position, posture to third position, posture, and then finishes measurement of the measurement points P1 to P9 at each position. Until the termination is instructed, the processes in steps S13 to S17 are repeated. As a result, three position data corresponding to each position of the set point P are transmitted to the robot controller 20. If step S18 is affirmed, the process proceeds to step S19 to output a signal to the robot controller 20 via the cable 31 to notify the end of the measurement mode.

  Next, processing of the robot controller 20 will be described. In step S21, it is determined whether or not the machine controller 10 has notified the mode change from the work mode to the measurement mode. When step S21 is affirmed, the process proceeds to step S22, and it is determined whether or not the position data of the set point P has been received from the machine controller 10. If step S22 is affirmed, the process proceeds to step S23, and if not, step S23 is passed and the process proceeds to step S24.

  In step S23, the position of the set point P in the robot coordinate system is obtained based on the position data of the robot control point Q and the positional relationship between the set point P and the control point Q on the predetermined robot coordinate system. The position data is stored in the memory of the robot controller 20. In step S <b> 24, it is determined whether or not the machine control controller 10 has notified the end of the measurement mode. If step S24 is positive, the process proceeds to step S25, and if negative, the process proceeds to step S22.

  In step S25, based on the three position data of the set point P on the machine tool coordinate system transmitted from the machine controller 10 and the corresponding three position data of the set point P on the robot coordinate system, A coordinate transformation matrix Ta from the robot coordinate system to the machine tool coordinate system is obtained, and a relative relationship between the machine tool coordinate system and the robot coordinate system is derived. In step S26, a work program is created or the coordinates of the existing program are converted using the transformation matrix Ta, and the work program is stored in the memory. Note that the same processing as in FIG. 7 is also performed when the robot hand 22 has the B shape and the C shape.

According to the present embodiment, the following operational effects can be achieved.
(1) The position data of the set point P on the robot coordinate system is obtained based on the known positional relationship of the set point P determined at the tip of the robot hand with respect to the robot control point Q by the processing in the robot controller 20 (step S23). In addition to the acquisition, position data of the set point P on the machine tool coordinate system is acquired by using the measuring instrument 14 attached to the machine tool 1 by the processing in the machine controller 10 (step S16). Based on the above, the relative relationship between the robot coordinate system and the machine tool coordinate system is derived by the process (step S25) in the robot controller 20. As a result, there is no need to provide the robot 2 with a position detector for measuring the set point P, and the machining system can be configured at low cost.

(2) When the claw 22a of the robot hand 22 has a substantially rectangular parallelepiped A shape (FIG. 4) and B shape (FIG. 5), the corners of the claw 22a at which three adjacent planes S1 to S3 of the substantially rectangular parallelepiped intersect each other Set point P was set. And while detecting the position of measurement point P1-P9 on surface S1-S3 with the measuring device 14, based on the position data of these measurement points P1-P9, the plane type of each surface S1-S3 is calculated, and plane type | formula is calculated. The position of the set point P is calculated by solving them simultaneously. Thereby, compared with the case where the probe is pressed against the corner of the claw 22a and the position of the set point P is directly measured by the measuring instrument 14, the measurement accuracy of the set point P is increased.
(3) When the claw 22b of the robot hand 22 has a substantially cylindrical C shape (FIG. 6), the set point P is set at the center of the upper end surface of the substantially cylindrical shape. And while detecting the position of the measurement points P1-P6 of an upper end surface and a cylindrical side with the measuring device 14, it calculates the intersections P7-P9 of an upper end surface and a cylindrical side based on the position data of these measurement points P1-P6, The position of the set point P is calculated based on the intersection points P7 to P9. Thereby, compared with the case where the probe is pressed against the center of the claw 22b and the position of the set point P is directly measured by the measuring instrument 14, the measurement system of the set point P is increased.
(4) A transformation matrix Ta representing the relative relationship between the robot coordinate system and the machine tool coordinate system is calculated by the processing in the robot controller 20 (step S25), and a work program for the robot 2 is created based on this transformation matrix. Since the coordinate transformation of the program is performed (step S26), the handling work can be performed with high accuracy.

  In the above embodiment, the robot hand 22 is moved to the first position, posture to third position, posture, and the position data of the set point P at each position is obtained. It is also possible to obtain four or more position data of the set point P by moving and derive the relative relationship between the robot coordinate system and the machine tool coordinate system based on these position data. If the number of set points P is large, the position accuracy can be further increased.

  If the set point P is determined at a location where the positional relationship with the robot control point Q is known, the set point P may be determined as a movable part other than the robot hand, and the position data of the set point P on the robot coordinate system. The configuration of the robot controller 20 as data acquisition means for acquiring is not limited to that described above. Although the probe is attached to the tool attachment portion of the tool post 12, the configuration of the measuring instrument 14 as the measuring means is not limited to this, and a non-contact measuring instrument such as a laser position detector may be used. Instead of attaching the measuring means to the machine tool, the measuring means may be provided at another location.

  If the position data of the set point P in the robot coordinate system and the machine tool coordinate system is 3 points or more, the relative relationship between the robot coordinate system and the machine tool coordinate system can be obtained, and the robot control controller as a relative relationship deriving means The processing at 20 may be any. When the claw 22a of the robot hand 22 has an A shape and a B shape, position data on three planes is detected by the measuring instrument 14 as a detection unit, and a set point is set by a signal processing unit of the machine control controller 10 as a calculation unit. The position of P is calculated. Further, when the claw 22b of the robot hand 22 is C-shaped, the position data of the upper end surface and the side surface of the cylinder are detected by the measuring instrument 14 as the detection unit, and the set point is set by the signal processing unit of the machine controller 10 as the calculation unit. Although the position of P is calculated, the configuration of the robot measuring means is not limited to this. The shape of the robot hand 22 is not limited to the A shape to the C shape described above.

  Although the present invention is applied to the machine tool 1 that processes the workpiece W, the present invention can be similarly applied to other machine tools such as an injection molding machine. That is, as long as the features and functions of the present invention can be realized, the present invention is not limited to the processing system of the embodiment.

DESCRIPTION OF SYMBOLS 1 Machine tool 2 Robot 10 Machine control controller 14 Measuring instrument 20 Robot control controller 22 Hand 22a, 22b Claw

Claims (3)

A machining system having a machine tool controlled by a machine tool control device and a robot controlled by a robot control device and performing work on the machine tool,
Data acquisition means for acquiring position data of the set point on a robot coordinate system determined for the robot based on a known positional relationship with respect to a robot control point of a set point determined for a predetermined movable part of the robot;
Measuring means for measuring the position of the set point on the machine tool coordinate system defined for the machine tool;
Based on the position data on the robot coordinate system acquired by the data acquisition means and the position data on the machine coordinate system measured by the measurement means, the robot coordinate system and the machine tool coordinate system A machining system comprising: a relative relationship deriving unit for deriving a relative relationship. The processing system according to claim 1,
The robot has a substantially rectangular parallelepiped claw in the hand part of the arm tip,
The set point is a corner of the nail where three adjacent planes of a substantially rectangular parallelepiped intersect each other,
The measuring means includes
A detector for detecting position data on the three planes;
A processing system comprising: an arithmetic unit that calculates the position of the set point based on the position data. The processing system according to claim 1,
The robot has a substantially cylindrical claw in the hand part of the arm tip,
The set point is the center point of the upper end surface of the substantially cylinder,
The measuring means includes
A detection unit for detecting position data of an upper end surface and a side surface of the substantially cylinder;
A processing system comprising: an arithmetic unit that calculates an intersection between the upper end surface and the side surface based on the position data, and calculates a position of the set point based on the intersection.

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