JP4584877B2 - Robot teaching system and robot teaching method - Google Patents

Description

  The present invention relates to a robot teaching system for use in teaching a workpiece transfer operation to a robot, and a controller, a teaching operation terminal, and a robot teaching method used therefor.

  Conventionally, there are robots that transfer workpieces such as semiconductor wafers and glass substrates between cassettes. This robot is previously taught a predetermined operation necessary for conveyance, and performs a desired teaching operation according to teaching data. The teaching data is input by a teaching operation terminal generally called a teaching pendant.

  In recent years, safety standards for robots have become stricter, and it is required to attach an enable switch for turning on / off the servo of the robot to the teaching pendant described above. This enable switch is an emergency stop for teaching the robot. For example, the servo switch is turned on when the robot is pressed, the servo is turned off when it is released, or when it is pressed lightly. The servo is turned on, and when it is released or pressed hard, the servo is turned off.

  Ideally, it is preferable that the movable part (for example, an arm or the like) of the robot is completely stopped at the moment when the servo is turned off by releasing the enable switch. This is because if the movable part of the robot moves after the servo is turned off, the current position coordinates are shifted, and complicated work is required to restart the teaching operation that has been stopped in an emergency. In some cases, the teaching operation must be repeated from the beginning. However, in reality, even if the servo is turned off, the movable part of the robot is slightly displaced (for example, dropped by a minute distance) due to, for example, gravity or inertia.

  Therefore, for example, there is a technique disclosed in Patent Document 1 in order to prevent the movable part of the robot from being displaced as little as possible when the servo is turned off. The safety device disclosed in Patent Document 1 does not immediately turn off the servo when the enable switch is released, but waits for the brake to function sufficiently before turning off the servo. As a result, the amount of displacement by which the movable part of the robot is slightly displaced after the servo is turned off can be reduced.

JP-A-6-206183 (paragraph [0016])

  However, even with the safety device disclosed in Patent Document 1, it is difficult to make the amount of displacement that the movable part of the robot slightly displaces after the servo is turned off almost zero. That is, when the servo is turned off, there is a high possibility that a deviation of about several millimeters (several pulses to several tens of pulses in terms of the number of pulses) occurs, for example, the arm drops 0.1 mm. In particular, the larger the robot is, the more difficult it is to suppress this shift. Further, after the servo is turned off, a deviation of about several millimeters may occur, for example, when an operator touches the robot.

  On the other hand, it is possible to prevent such a shift from occurring by continuing to press the enable switch during teaching work. However, this makes it impossible for the worker to rest his hands at all. There is a risk of pain.

  The present invention has been made in view of such a point, and the purpose thereof is to perform teaching operation from the beginning even if the movable part of the robot is slightly displaced after the servo is turned off. It is an object of the present invention to provide a robot teaching system capable of easily restarting a teaching operation stopped when a servo is turned off such as in an emergency stop, a controller, a teaching operation terminal, and a robot teaching method used therefor.

  In order to solve the above problems, the present invention provides the following.

(1) A robot teaching system having a robot that operates based on the taught position information, a controller that operates the robot based on a predetermined program, and a teaching operation terminal that teaches the position information to the robot. The memory is provided in one or both of the controller and the teaching operation terminal, and stores the position coordinate A immediately before the teaching operation of the robot is stopped by turning off the servo during teaching work. Means, a return means provided in the teaching operation terminal for giving an opportunity to resume the stopped teaching operation, and when the teaching operation is resumed, the robot is moved back from the current position coordinate B to the position coordinate A. A robot teaching system comprising: return control means for performing control.

  According to the present invention, in a robot teaching system having a robot, a controller, and a teaching operation terminal, when the teaching operation of the robot is stopped by turning off the servo, it is possible to store the position coordinate A immediately before that. When the teaching operation is resumed after providing the means on one or both of the controller and the teaching operation terminal, and providing the teaching operation terminal with return means (for example, a return switch) that gives an opportunity to resume the stopped teaching operation. In addition, since the robot is provided with return control means for performing control to return the robot from the current position coordinate B to the position coordinate A, the stopped teaching operation can be easily restarted.

  In other words, even when the movable part of the robot is slightly displaced after the servo is turned off, the operator can simply use the return means (for example, by simply pressing the return switch) to move the robot to the current position coordinate B. Therefore, it is possible to return to the desired position coordinate A immediately before the teaching operation stops. Therefore, the stopped teaching operation can be easily restarted without having to restart the teaching operation from scratch. Further, during the teaching work, it is not necessary to keep pressing the enable switch for a long time, so that it is possible to suppress physical distress to the worker, and to improve the efficiency of the teaching work.

  For example, if the cassette for loading and unloading the workpiece is a glass substrate cassette, the teaching data for the rotation axis and the traveling axis are taught for the purpose of matching the movement of the arm. Need to be. Further, in the case of Z-axis teaching data, the teaching data before and after the cassette needs to match if the robot and the cassette are correctly leveled. And when an operator is an expert, there exists a situation that it is sensitive to the relationship of these numerical values. Therefore, in the conventional robot teaching system, the skilled person tries to keep pressing the enable switch in order to avoid inconsistency of teaching data (for example, in the case of the coordinate value of teaching data, the difference between 100.000 mm and 99.999 mm). There was a trend. However, this does not allow the skilled person to rest, resulting in physical distress. In this respect, in the robot teaching system according to the present invention, even if the movable part of the robot is slightly displaced after the servo is turned off, the displacement amount can be made substantially zero afterwards ( Since the robot can be moved back from the current position coordinate B to the desired position coordinate A), it is possible to prevent the skilled person from being physically painful.

  Here, the “teaching operation terminal” may be a general teaching pendant or an information processing terminal such as a PC or a PDA. The “position coordinate A” stored in the storage means may be one position coordinate immediately before the robot teaching operation stops by turning off the servo, or before the robot teaching operation stops. There may be a plurality of (for example, two) position coordinates, and the number of position coordinates does not matter. In addition, when the robot teaching operation “stops when the servo is turned off”, not only when the operator consciously operates the enable switch etc., but also when the emergency stop button is pressed down or the worker is unconscious. This includes emergency stops such as when the enable switch is operated.

  (2) The robot teaching system according to (1), wherein the teaching operation terminal includes an enable switch that stops the teaching operation of the robot by turning off a servo.

  According to the present invention, the teaching operation terminal described above is provided with an enable switch that stops the teaching operation of the robot by turning off the servo. When it is desired to take a rest, the teaching operation of the robot can be stopped at a desired timing using this enable switch. Then, the stopped teaching operation can be easily restarted by using the storage means, the return means, and the return control means described above.

  (3) The robot teaching system according to (2), wherein the teaching operation of the robot is emergency stopped by the enable switch or an emergency stop button provided separately from the enable switch.

  According to the present invention, the servo of the controller is turned off by the above-described enable switch or the emergency stop button provided separately from the above-mentioned enable switch. Can do.

  (4) The robot teaching system according to any one of (1) to (3), wherein the teaching operation terminal includes display means for displaying the position coordinates A and the current position coordinates B.

  According to the present invention, the teaching operation terminal described above is provided with the display means for displaying the position coordinates A and the current position coordinates B, so that the operator can use not only the current position coordinates B of the robot but also the robot. It is possible to visually confirm the position coordinate A immediately before the teaching operation of FIG.

  (5) The teaching operation terminal includes axis selection means for selecting any one or two or more axes among the plurality of axes constituting the position coordinates A and the current position coordinates B, and the return control means The robot teaching system according to any one of (1) to (4), wherein control is performed to return the robot to the axis selected by the axis selection means.

  According to the present invention, the teaching operation terminal described above is provided with axis selection means for selecting any one or more of the plurality of axes constituting the position coordinate A and the current position coordinate B. The return control means controls the return movement of the robot with respect to the axis selected by the axis selection means. For example, the position coordinates A and the current position coordinates B are shifted with respect to some axes instead of all axes. In this case, the robot can be returned and moved only about the offset axis, and as a result, teaching work using direct teaching can be performed quickly and efficiently. That is, when direct teaching is performed by moving the robot directly by hand in a state where the servo is stopped by turning off the servo, there may be a slight displacement on an axis other than the axis that is the target of direct teaching. Even in such a case, it is possible to realize a quick and efficient return movement by moving the robot back about only a slightly displaced axis. Note that direct teaching can generally be performed on a brake-free axis or a servo-free axis.

  (6) The robot teaching system according to any one of (1) to (5), wherein the position coordinate A is a coordinate of a final position in a state where the servo of the controller is on.

  According to the present invention, since the position coordinate A described above is the coordinate of the final position when the servo of the controller is on, the servo among the position coordinates A stored in the storage means is It is possible to move the robot back to the position coordinates closest to the moment of turning off.

The controller is a controller that operates a robot that operates based on the taught position information based on a predetermined program, and when the teaching operation of the robot is stopped by turning off the servo, the position coordinates immediately before that you further comprising a storage means for storing the a.

  According to the present invention, a controller including storage means for storing the position coordinate A immediately before the robot teaching operation is stopped by turning off the servo is provided. When the robot is stopped by turning it off, the robot can be returned to the position coordinate A immediately before the robot is stopped.

The teaching operation terminal is a teaching operation terminal for teaching the position information to a robot that operates based on the taught position information, and when the teaching operation of the robot is stopped by turning off the servo, you further comprising a storage means for storing position coordinates a immediately before.

  According to the present invention, there is provided a teaching operation terminal provided with a storage means for storing the position coordinate A immediately before the robot teaching operation is stopped by turning off the servo. When stopped by turning off the servo, the robot can be returned to the position coordinate A immediately before the robot is stopped.

(7) In the robot teaching method of teaching operation to the robot having a drive shaft which is servo-controlled by using the teaching operation terminal, a setting step of setting a target position coordinates C of the robot, to the target location coordinates C A moving step of moving the robot toward the robot, a robot position storing step of storing the position coordinates of the robot at predetermined time intervals during the moving step, and a teaching operation of the robot during the teaching operation. When the robot is turned off and stopped, the stop position storage step for storing the position coordinate A immediately before the robot teaching operation stops out of the position coordinates stored in the robot position storage step, and the servo control is turned off. A current position storage step for storing the current position coordinates B of the robot after the present time, and the current position coordinates B when the teaching operation is resumed. Robot teaching method characterized by including: a recovery control step of performing control to return movement to the position coordinates A.

  According to the present invention, in the robot teaching method, a step of setting the target position coordinates C of the robot and storing the position coordinates of the robot at predetermined time intervals while moving the robot toward the target position coordinates C; A step of storing (in the teaching operation terminal or the robot controller) the position coordinate A immediately before the stop of the stored position coordinates when the servo control is turned off and stopping, and the current state of the robot after the servo control is turned off Since it includes the step of storing the position coordinate B (in the teaching operation terminal or the robot controller) and the step of performing the control of returning from the position coordinate B to the position coordinate A when the teaching operation is resumed. Even if the moving part of the robot is slightly displaced after the servo is turned off, the amount of displacement can be reduced to almost zero afterwards, and consequently stopped. Was teaching operation can be resumed in a simple manner. In addition, the operator can be freed from physical pains such as having to keep pressing the enable switch.

(8) The teaching operation terminal may include one or two of a display unit that displays the position coordinates A and the current position coordinates B, and a plurality of axes that constitute the position coordinates A and the current position coordinates B. An axis selection means for selecting the above axes, a coordinate display step for displaying the position coordinates A and the current position coordinates B for each constituent axis on the display means, and the position coordinates A and the current position. An axis selection step of selecting any one or more of the plurality of axes constituting the coordinate B, and the return control step returns the robot with respect to the axis selected in the axis selection step (7) The robot teaching method according to (7), wherein control is performed to move the robot.

  According to the present invention, in the robot teaching method described above, the position coordinate A and the current position coordinate B are displayed for each constituent axis on the display means for displaying the position coordinate A and the current position coordinate B. Since one or two or more axes are selected and the robot is controlled to return and move on the selected axes, the teaching operation using the direct teach is quickly performed in the same manner as the invention described in (5) above. And can be performed efficiently.

  As described above, according to the robot teaching system according to the present invention, the controller used in the robot teaching system, the teaching operation terminal, and the robot teaching method, the moving part of the robot is slightly displaced when the servo is turned off. However, just using the return means (for example, by simply pressing the return switch), the amount of displacement can be reduced to almost zero afterwards, so the stopped teaching operation can be performed without re-starting the teaching operation from scratch. It can be restarted easily.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

[Robot teaching system configuration]
FIG. 1 is a configuration diagram of a robot teaching system according to an embodiment of the present invention. 2 is an external view (side view) showing an external configuration of the teaching operation terminal 300 in the robot teaching system shown in FIG.

  As shown in FIG. 1, the robot teaching system includes a robot 100, a robot controller 200, and a teaching operation terminal (teaching pendant) 300. The robot 100 operates based on the taught position information, the robot controller 200 operates the robot 100 based on a predetermined program, and the teaching operation terminal 300 sends the position information to the robot 100. It is for teaching. As shown in FIGS. 1 and 2, the teaching operation terminal 300 is provided with an LCD display (an output unit 305 to be described later) at the center of the surface, and an emergency stop switch 3043 at the upper right of the LCD display. In addition, a return switch 3041 is provided on the lower right side of the LCD display to give an opportunity to resume the teaching operation when the teaching operation of the robot 100 is stopped by turning off the servo. Further, an enable switch 3044 for turning on / off the servo of the robot controller 200 is provided on the back side of the teaching operation terminal 300, and a grip portion 3045 for gripping an operator is provided on the back surface (FIG. 2). reference). The enable switch 3044 is provided integrally or in proximity to the grip portion 3045 so that the operator can simultaneously press the grip portion 3045 when the operator grips and operates the grip portion 3045.

  In FIG. 1, the robot 100 and the robot controller 200, and the robot controller 200 and the teaching operation terminal 300 are electrically connected by wire such as a serial cable. However, the present invention is not limited to this, and infrared communication, It may be electrically connected by radio such as distance wireless communication (Bluetooth). Further, it may be connected via a LAN, the Internet, or the like.

  The outline of the robot teaching system according to the embodiment of the present invention will be described. When the teaching operation of the robot 100 is stopped by turning off the servo, when the operator presses the return switch 3041, the teaching operation terminal 300 and the robot This is a system in which a movable part (for example, arms 15A and 15B described later) of the robot 100 is moved back to a position coordinate immediately before the teaching operation of the robot 100 stops by the controller 200. A RESUME LED 3042 is provided above the return switch 3041 (see FIG. 1).

[Robot 100 mechanical configuration]
In FIG. 1, a double arm type robot is employed as the robot 100. The robot 100 includes a base 11, a rotation unit 12, a column 13, a slider 14 (a support member that supports the arms 15A and 15B), and arms 15A and 15B. The arm 15A has a hand fork portion 16a and a hand base end portion 16b (the same applies to the arm 15B). Further, the arm 15A is rotatably connected by the first joint portion 17a, the second joint portion 17b, and the third joint portion 17c, so that the rotational force from the rotational drive source can be transmitted to perform a desired operation. (The same applies to the arm 15B).

  The rotation unit 12 is rotatably arranged on the base 11, and the rotation of the rotation unit 12 allows the robot 100 to turn and change its direction. That is, the rotation unit 12 can rotate Θ around the Z axis. The rotating unit 12 can be moved in the Y-axis direction in the figure by a horizontal movement mechanism (not shown). Furthermore, the slider 14 is configured to be slidable up and down on the side surface of the column 13 (movable in the Z-axis direction in the figure).

  As described above, the arm 15A provided in the robot 100 includes the first arm portion 18 and the first arm portion together with the three joint portions (the first joint portion 17a, the second joint portion 17b, and the third joint portion 17c). 18 and a second arm portion 19 connected to the same (also applies to the arm 15B).

  A base end of the first arm portion 18 is connected to the slider 14 via a drive shaft, and constitutes a rotatable first joint portion 17a. In addition, the base end of the second arm portion 19 that is the tip of the first arm portion 18 is connected via a drive shaft to constitute a rotatable second joint portion 17b. Further, the distal end of the second arm portion 19 and the hand base end portion 16b are connected via a drive shaft to constitute a rotatable third joint portion 17c.

  The two sets of arms 15A and 15B are rotated by the first joint portion 17a, the second joint portion 17b, and the third joint portion 17c by a rotation drive source (not shown), and the hand fork portion 16a and the hand base end portion 16b. Is moved in the direction of taking out and supplying the workpiece 10. At this time, in the arm 15A, due to its mechanism, the hand fork portion 16a and the hand base end portion 16b face one direction, and the first arm portion 18 and the second arm portion 19 are fully extended. The arm portion 18 and the second arm portion 19 are folded, and an expansion / contraction operation is performed so as to linearly move between the contraction positions. That is, in this embodiment, it reciprocates in the X direction in the figure. Then, the substrate (work 10) is stored in the cassette located at the extended position, or the work 10 is carried out to the retracted position (the same applies to the arm 15B). Such a mechanism is provided with a timing pulley in each of the first joint portion 17a, the second joint portion 17b, and the third joint portion 17c, and the timing pulleys are connected to each other by a timing belt. It is comprised so that rotation can be performed (same also about the arm 15B).

The arms 15A and 15B are disposed on the slider 14 so as to face each other in the vertical direction so as not to interfere with each other. That is, the arms 15A and 15B are arranged so that the rotation center axis of the first joint portion 17a is coaxial. Thereby, it becomes possible to arrange | position so that two sets of arms 15A and 15B may not contact mutually, The supply operation | movement of the workpiece | work 10 and the taking-out operation | movement of another workpiece | work 10 can be performed efficiently. ing. Further, movements in the respective X-axis, Y-axis, Z-axis, and Θ-axis directions in the figure are controlled by servo motors 110b _{1 to} 110b _n (see FIG. 3 described later) that are servo-controlled in the robot 100. It has become so.

  In the present embodiment, a double arm type robot that conveys a glass substrate as an example of work is illustrated, but the present invention is not limited to this, and is applicable to other types of robots and other industrial equipment. can do.

[Electric configuration of robot teaching system]
FIG. 3 is a block diagram showing electrical configurations of the robot 100 and the robot controller 200 in the robot teaching system according to the embodiment of the present invention.

  In FIG. 3, the robot controller 200 includes a CPU 101, a ROM 102, a RAM 103, an EEPROM 104, a communication I / F 105, an external input / output I / F 106, and a servo control unit 110, which are connected by a bus. Has been.

  The CPU 101 controls the robot controller 200 and performs integrated control of the robot controller 200. The ROM 102 stores a system program that supports the basic functions of the robot controller 200. The RAM 103 functions as a working area for the CPU 101. That is, in the RAM 103, writing and reading of variable values are performed at random. The EEPROM 104 can be electrically erased and written any number of times, and can retain the memory without supplying power from the outside.

A teaching operation terminal 300 (an information processing apparatus such as a personal computer) as an information processing terminal is connected to the communication I / F 105, and various data and programs for robot control are input / output. Although not shown, the external input / output I / F 106 is connected to a sensor provided in the robot, an actuator of a peripheral device, or the like. The servo controller 110 includes servo controllers 1 to n (n: the total number of axes of the robot plus the number of movable axes of the tool), and arithmetic processing (trajectory creation and interpolation, reverse operation) for robot control. receiving a control command created through conversion, etc.), the servo motor 110b ₁ ~110b _n constituting the actuator of each axis of the robot mechanical unit, controlled via the servo amplifiers 110a ₁ ~110a _n.

  FIG. 4 is a block diagram showing an electrical configuration of teaching operation terminal 300 in the robot teaching system according to the embodiment of the present invention.

  4, the teaching operation terminal 300 includes a CPU 301, a ROM 302, a RAM 303, an input unit 304, an output unit 305, and a communication unit 306, and each component is connected by a bus.

  The CPU 301 serves as a control center of the teaching operation terminal 300 and performs various controls according to a program stored in the ROM 302. The RAM 303 functions as a working area for the CPU 301. The input unit 304 includes a linear operation key, a rotation operation key, each axis operation key in the various coordinate systems, the return switch 3041 (see FIG. 1) described above, and the like. The output unit 305 includes an LCD display, the above-described RESUME LED 3042 (see FIG. 1), or a sound output device such as a speaker. The communication unit 306 is electrically connected to the communication I / F 105 (FIG. 3) of the robot controller 200. The CPU 301 performs input of operation commands for the robot 100 and monitoring of information such as position and operation via the communication unit 306 and the robot controller 200.

  Here, in the robot teaching system according to the present embodiment, the RAM (memory) 103 of the robot controller 200 can store the previous position coordinates when the teaching operation of the robot is stopped by turning off the servo. It is possible. The CPU 101 of the robot controller 200 can write / read position coordinates to / from the RAM (memory) 103. In the following [Information processing flow], description will be given using two memories (memory 1 and memory 2). However, the present invention is not limited to this, and one or three or more memories may be used. . Further, the storage area in one RAM 103 may be divided into a plurality of pieces and used as a plurality of memories.

[Information processing flow]
FIG. 5 is a flowchart showing a flow of information processing in the robot teaching method according to the embodiment of the present invention. In particular, FIG. 5 focuses on the flow of information processing in the robot controller 200. Further, FIG. 5 focuses on the information processing flow in the middle of the moving process of setting the target position coordinates of the robot and moving the robot 100 toward the target position coordinates.

  In FIG. 5, first, the robot controller 200 (the CPU 101 thereof) reads the current position coordinates of the robot 100 (for example, the arms 15A and 15B) (step S1). At this time, not the position coordinates but the number of pulses may be read and the robot controller 200 may perform coordinate conversion.

  Then, the robot controller 200 determines whether or not the servo is on (step S2). If the servo is on (step S2: YES), the read position coordinates are stored in the memory 1. (Step S3). On the other hand, if the servo is not on (step S2: NO), the coordinates stored in the memory 1 are substituted into the memory 2 (step S4). In this embodiment, the servo can be switched from the on state to the off state by releasing the enable switch 3044 (see FIG. 2) provided in the teaching operation terminal 300, and conversely, the enable switch 3044 (see FIG. 2). 2), the servo can be switched from the off state to the on state. Hereinafter, the operations of Step S1 to Step S4 are periodically executed. The flow of information processing shown in FIG. 5 will be described visually and conceptually with reference to FIG.

  FIG. 6 is an explanatory diagram for visually and conceptually understanding the flowchart shown in FIG.

  As shown in FIG. 6, the robot controller 200 (the CPU 101 thereof) reads the current position coordinates of the robot 100 at a constant cycle (time interval) (FIG. 6A). When the servo is on (FIG. 6B at timings “1” to “5” in FIG. 6A), the read position coordinates are stored in the memory 1 (overwritten and saved). (FIG. 6C).

  At timing “6” in FIG. 6A, it can be seen that the teaching operation of the robot has stopped due to an emergency stop or the like because the servo is in an OFF state. At this time, the memory 1 stores the position coordinates (position coordinates at the timing “5” in FIG. 6A) immediately before the robot teaching operation stops, and the memory 2 stores the position coordinates. Will be. That is, as shown in FIG. 6D, when the teaching operation of the robot 100 is stopped and the servo control is turned off, the position coordinates immediately before the teaching operation stops (timing “5” in FIG. 6A). "Position coordinates at") is stored in the robot controller 200 (memory 2 thereof).

  The position coordinates stored in the memory 2 are used when the teaching operation stopped by turning off the servo is resumed (FIG. 6E). Specifically, when the servo transitions from the off state to the on state (at timing “9” in FIG. 6A), the position coordinates stored in the memory 2 are read into the teaching operation terminal 300 and taught. The position coordinates read into the operation terminal 300 are valid until the servo again shifts to the off state (timing “9” to “11” in FIG. 6A).

  FIG. 7 is a flowchart showing a flow of information processing in the robot teaching method according to the embodiment of the present invention. In particular, FIG. 7 focuses on the flow of information processing (pendant processing) in the teaching operation terminal 300.

  In FIG. 7, when the servo is first turned on, an initial flag is set (step S11). More specifically, when the servo is first turned on, the CPU 301 of the teaching operation terminal 300 sets an initial flag in the storage area of the RAM 303.

  Next, the CPU 301 of the teaching operation terminal 300 determines whether or not the servo has transitioned from the off state to the on state (step S12). If it is determined that the servo has transitioned (step S12: YES), the CPU 303 accesses the RAM 303. Then, it is determined whether or not the initial flag is set (step S13). If it is determined that the initial flag is not set (step S13: NO), a RESUME process (see FIG. 8) described later is executed (see FIG. 8) (see FIG. 8). Step S14). On the other hand, if it is determined that the initial flag is set (step S13: YES), the initial flag is turned off (step S15) without performing the RESUME process described later (step S15), and other operations are performed (step S13). S16). Even when it is determined that the servo has not transitioned from the off state to the on state (step S12: NO), other operations are performed without executing the RESUME process described later (step S16). Moreover, the process of step S12-step S16 is repeatedly performed as shown in FIG.

  In this way, when the servo first transitions from the off state to the on state, the RESUME process is not particularly executed. However, when the servo transitions from the off state to the on state for the second and subsequent times, the RESUME process is performed. Then, the robot 100 can be returned from the current position coordinates to the desired position coordinates immediately before the teaching operation is stopped by turning off the servo.

  FIG. 8 is a flowchart for explaining a “RESUME processing” subroutine in the flowchart shown in FIG. 7.

  In FIG. 8, when the servo transitions from the off state (robot 100 is stopped) to the on state (step S12 in FIG. 7: YES) and the initial flag is not on (step S13 in FIG. 7). : NO), the CPU 301 of the teaching operation terminal 300 accesses the robot controller 200 via the communication unit 306, and reads the current position coordinates of the robot 100 and the above-described position coordinates stored in the memory 2 (step S21). ). Note that the read position coordinates are temporarily stored in the RAM 303.

  Next, the CPU 301 determines whether or not the two position coordinates stored in the RAM 303 in the process of step S21 match (step S22). If it is determined that they match (step S22: YES), this subroutine ends. On the other hand, if it is determined that they do not match (step S22: NO), the RESUME LED 3042 (see FIG. 1) blinks (step S23), and the operator is prompted to perform return control. Then, it waits until a certain switch is pushed by the operator (step S24: NO, step S25: NO).

  If the operator does not press the return switch (EXEC Key) 3041 (step S24: NO) and presses another switch (Other Key) (step S25: YES), the RESUME function is discarded. Assuming (step S26), the CPU 301 turns off the RESUME LED 3042 (see FIG. 1) (step S34).

  On the other hand, when the operator presses the return switch 3041 (step S24: YES), the CPU 301 transmits an image display control signal to the output unit 305, and the position stored in the RAM 303 by step S21. The coordinates are displayed on the LCD display (step S27).

  Next, the CPU 301 determines which key on the teaching operation terminal 300 is pressed (step S28), and when the reset (RESET) key is pressed, determines that the RESUME function is to be discarded (step S26). , RESUME LED 3042 (see FIG. 1) is turned off (step S34). Further, when a predetermined key is operated (for example, an axis is selected by using the ↑ ↓ key (arrow key) and whether or not the operation can be performed by using the ← → key (arrow key)) (step S29), which will be described later. In the return movement, the robot 100 is returned and moved only about the selected axis.

  Next, when the return switch (EXEC Key) 3041 is pressed again, the CPU 301 distinguishes between the axis checked in step S29 and the axis not checked (step S30). A command signal for substituting the value of the memory 2 into the target value is transmitted to the robot controller 200 (step S31). For an unchecked axis, a command signal for substituting the value of the current coordinate position into the target value. It transmits to the robot controller 200 (step S32).

  Receiving such a command signal, the robot controller 200 (the CPU 101 thereof) moves the robot 100 back to the target value coordinates set for each axis (step S33). Accordingly, in the present embodiment, the teaching operation terminal 300 (CPU 301 thereof) that transmits a command signal and the robot controller 200 that operates the robot 100 based on the command signal function as an example of “return control means”. After the process of step S33 is completed, the CPU 301 turns off the RESUME LED 3042 (see FIG. 1) (step S34), and this subroutine is completed.

  FIG. 9 is a diagram illustrating an example of display contents on the screen of the output unit 305 (LCD display) of the teaching operation terminal 300.

  First, FIG. 9A shows that the current position coordinate B of the robot 100 is displayed on the screen of the teaching operation terminal 300 by pressing the return switch (EXEC Key) 3041 of the teaching operation terminal 300 when using the RESUME function. (Current Pos.) And position coordinates A (Resume Pos.) Immediately before the robot 100 teaching operation stops when the servo is turned off are displayed for each constituent axis (step in FIG. 8). S24 → step S27). In FIG. 9A, a check box (dotted line frame X) is displayed next to the axis to which the robot 100 is to be returned and only the axis to be returned is checked. Specifically, in FIG. 9A, only the axis Y1, the axis Z1, and the axis X2 are checked. As described above, by using the check box (dotted line frame X) to select the axis to be returned, the teaching work using the direct teaching can be performed quickly and efficiently. Details of this will be described later with reference to FIG.

  Next, FIG. 9B shows a state when the return switch (EXEC Key) 3041 of the teaching operation terminal 300 is pressed after selecting an axis. In the upper right corner of the screen, "Moving ..." is displayed. For example, when the return switch 3041 is released halfway, the characters “Aborted.” Are displayed on the upper right of the screen, and the return process is interrupted (see FIG. 9C). On the other hand, when the return switch 3041 is continuously pressed and the position coordinate B of the robot 100 matches the position coordinate A immediately before the robot 100 teaching operation stops when the servo is turned off, "Arrived." Is displayed, and the restoration process is completed (see FIG. 9D).

  In this way, the operator can freely select an axis to be returned and moved while visually recognizing the screen of the teaching operation terminal 300, and can return the robot only for the selected axis. In FIG. 9, there may be a case where the position coordinate B (Current Pos.) Of the robot 100 does not change. This is because the amount of movement that the robot 100 actually returns is very small.

  FIG. 10 is an explanatory diagram for explaining teaching work using direct teaching in the robot teaching system according to the present embodiment. In particular, FIG. 10 shows a state when the glass substrate (work 10) is transferred (reserved) to the cassette. Further, Pos1 in FIG. 10 indicates a position (positional coordinates) for placing the glass substrate in the cassette, and Pos2 in FIG. 10 indicates a position (positional coordinates) in which the glass substrate is pulled out from the cassette.

  In FIG. 10, first, in the teaching work, when the R axis (corresponding to the X axis in FIG. 1) is moved back and forth, the Θ axis and the traveling axis (in FIG. 1) so that the glass substrate and the cassette are parallel to each other. (Corresponding to the Y axis) is taught (running together). And if it runs well, you only have to teach the position of the R axis.

  When teaching Pos1 after teaching Pos1 in this way, JOG operation (using the teaching operation terminal 300 and manually monitoring information such as command input and position / operation while teaching Pos2) Rather than returning the arm in the R-axis direction (for example, the arms 15A and 15B shown in FIG. 1) in the operation to be performed), turning off the servo and returning the arm directly in the R-axis direction by hand, that is, direct teaching May be simple. Therefore, consider the case of direct teaching from Pos1 to Pos2.

  However, in the case of direct teaching from Pos1 to Pos2, there is a case where it is displaced in the axial direction which is not desired to move originally.

  For example, the coordinates of Pos1 are (R axis, Θ axis, travel axis) = (201, 89, 100) and are taught. After the servo is turned off, if the arm is moved by hand in the R-axis direction and direct teaching is performed, ideally, the coordinates of Pos2 (R-axis, Θ-axis, travel axis) = (100, 89, 100) Is preferred. However, in actuality, the robot arm is displaced in the axial direction of the Θ axis and the traveling axis that are not desired to move. , 99.5).

  Therefore, in such a case, the R axis is not checked, but only the Θ axis and the traveling axis are checked (by making only the Θ axis and the traveling axis as the axes to be returned), the servo is When turned on, the RESUME process is executed as described with reference to FIGS. 8 and 9, and the coordinates of Pos 2 (R axis, Θ axis, travel axis) originally intended for the robot 100 = (100, 89, 100) It can be moved back to.

[Effect of the embodiment]
As described above, according to the robot teaching system, the controller used in the robot teaching system, the teaching operation terminal, and the robot teaching method according to the present embodiment, the robot 100 (movable part thereof) is minute after the servo is turned off. Even in the case of displacement, the operator simply uses the return switch 3041 in the teaching operation terminal 300 to stop the robot 100 from the current position coordinate B (Current Pos.) By turning off the servo. Since it can be easily returned to the desired position coordinate A (Resume Pos.) Just before starting, the stopped teaching operation can be easily resumed without re-starting the teaching operation from the beginning. Can be streamlined. Further, the desired position coordinate A (Resume Pos.) Immediately before the teaching operation is stopped by turning off the servo is displayed on the screen of the teaching operation terminal 300, so that the movement amount (or It is possible to visually check how much the current position and return position are deviated on each axis.

  Furthermore, since the teaching operation terminal 300 is provided with a predetermined key capable of selecting an axis to which the robot 100 is to be returned and moved, the operator operates the key to select the selected axis. Only the robot 100 can be moved back, and as a result, teaching work using direct teaching can be performed quickly and efficiently (see FIG. 10). Note that all-axis return may be selected by default.

[Modification]
In the embodiment described above, the desired position coordinate A (Resume Pos.) Immediately before the teaching operation is stopped by turning off the servo is also stored in the RAM 303 of the teaching operation terminal 300. However, the data may be stored only in the memory (RAM 103) of the robot controller 200.

  Further, in the above-described embodiment, one position coordinate immediately before the robot teaching operation stops by turning off the servo is stored in the memory (RAM 103) of the robot controller 200 (in FIG. The position coordinate of “5” is stored in the memory 2), and the present invention is not limited to this. For example, using three memories, the two position coordinates before the robot teaching operation stops are stored. Also good. Details will be described with reference to FIGS. 11 and 12.

  FIG. 11 is a flowchart showing a flow of information processing in a robot teaching method according to another embodiment of the present invention. In particular, FIG. 11 focuses on the flow of information processing in the robot controller 200. Further, FIG. 11 focuses on the flow of information processing in the middle of the moving process of setting the target position coordinates of the robot and moving the robot 100 toward the target position coordinates.

  In FIG. 11, the robot controller 200 (CPU 101) first reads the current position coordinates of the robot 100 (step S41) as in FIG. 5, and determines whether the servo is on (step S42). If it is on, the read position coordinates are stored in the memory 1 (step S43).

  On the other hand, if the servo is not on (step S42: NO), the robot controller 200 determines whether or not the position coordinates stored in the memory 1 are different from the position coordinates stored in the memory 2. Judgment is made (step S44). If they are different (step S44: YES), the position coordinates stored in the memory 2 are substituted into the memory 3, and then the position coordinates stored in the memory 1 are substituted into the memory 2 (step S45, step S45). S46). Conversely, if they are not different (step S44: NO), the position coordinates stored in the memory 1 are substituted into the memory 2 without substituting the position coordinates stored in the memory 2 into the memory 3 ( Step S46). In addition, the operation | work of step S41-step S46 is performed periodically.

  The flow of information processing shown in FIG. 11 will be described visually and conceptually with reference to FIG.

  FIG. 12 is an explanatory diagram for visually and conceptually understanding the flowchart shown in FIG.

  As shown in FIG. 12, the robot controller 200 (the CPU 101) reads the current position coordinates of the robot 100 at a constant cycle (time interval) (FIG. 12 (a)). Then, when the servo is in an ON state (in the timings “1” to “5”, “9” to “11”, “15” to “18”, “21” to “23” in FIG. 12A). 12 (b)), the read position coordinates are stored (overwritten and saved) in the memory 1 (FIG. 12 (c)).

  Here, for example, at timing “12” in FIG. 12A, the servo is turned off and the teaching operation of the robot is stopped. At this time, the position coordinates at the timing “11” and the position coordinates at the timing “5” are stored in the memory 1 and the memory 2 immediately before the servo is turned off. Therefore, since they are different (step S44: YES in FIG. 11), after the position coordinates at the timing “5” stored in the memory 2 are substituted into the memory 3 (FIG. 12 (e), step in FIG. 11). S45), the position coordinates at the timing "11" stored in the memory 1 are substituted into the memory 2 (FIG. 12 (d), step S46 in FIG. 11).

  Next, at timing “13” in FIG. 12A, the servo is still in an off state, and the teaching operation of the robot is stopped. At this time, in the memory 1 and the memory 2 immediately before the timing “13” (at the timing “12”), the position coordinates at the timing “11” and the position coordinates at the timing “11” are stored, respectively. Therefore, since both coincide (step S44: NO in FIG. 11), the position coordinate at the timing “11” stored in the memory 1 is substituted into the memory 2 (in FIG. 12D and FIG. 11). In step S46), the position coordinate stored at the timing "5" stored in the memory 3 remains unchanged.

  Then, for example, at the timing “15” in FIG. 12A, when the servo is turned on and the robot 100 is returned and moved, the operator uses the teaching operation terminal 300 to store the optimum position coordinates (stored in the memory 2). The position coordinates at the timing “11” or the position coordinates at the timing “5” stored in the memory 3) are selected, and the robot 100 can be moved back.

  As described above, if the position coordinates immediately before turning off the servo are prepared for only one time, when the enable switch 3044 (see FIG. 2) is continuously turned on and off twice or more, it is originally required 1 The value of the first time may not be displayed. Therefore, as described above, the position coordinates for two times (in FIG. 12, the position coordinates at the timing “11” stored in the memory 2 or the position coordinates at the timing “5” stored in the memory 3). ) Are prepared and displayed on the screen of the teaching operation terminal 300. Thereby, the worker can select a position coordinate that he / she needs and can instruct a RESUME operation. In FIG. 12, only the position coordinates for the past two times are considered, but the number of position coordinates is not limited, for example, the position coordinates for the past ten times are stored.

  As described above, the present invention can provide a teaching operation that is stopped by turning off the servo by simply correcting the minute displacement even when the movable part of the robot is slightly displaced after the servo is turned off. It is useful as something that can be resumed.

It is a block diagram of the robot teaching system which concerns on embodiment of this invention. It is an external view which shows the external appearance structure of the teaching operation terminal in the robot teaching system shown in FIG. It is a block diagram which shows the electrical structure of the robot and robot controller in the robot teaching system which concerns on embodiment of this invention. It is a block diagram which shows the electrical structure of the teaching operation terminal in the robot teaching system which concerns on embodiment of this invention. It is a flowchart which shows the flow of the information processing in the robot teaching method which concerns on embodiment of this invention. FIG. 6 is an explanatory diagram for conceptually understanding the flowchart shown in FIG. 5. It is a flowchart which shows the flow of the information processing in the robot teaching method which concerns on embodiment of this invention. It is a flowchart for demonstrating the subroutine of "RESUME process" in the flowchart shown in FIG. It is a figure which shows an example of the display content of the screen of the output part (LCD display) of a teaching operation terminal. It is explanatory drawing for demonstrating the operation | work which used the direct teaching together in the robot teaching system which concerns on this embodiment. It is a flowchart which shows the flow of the information processing in the robot teaching method which concerns on other embodiment of this invention. FIG. 12 is an explanatory diagram for visually and conceptually understanding the flowchart shown in FIG. 11.

Explanation of symbols

100 Robot 200 Robot Controller 300 Teaching Operation Terminal

Claims (8)

A robot that operates based on the taught position information;
A controller for operating the robot based on a predetermined program;
In a robot teaching system having a teaching operation terminal for teaching the position information to the robot,
A storage unit that is provided in one or both of the controller and the teaching operation terminal, and stores the position coordinate A immediately before the teaching operation of the robot is stopped by turning off the servo during teaching work ; ,
A return means provided in the teaching operation terminal for giving an opportunity to resume the stopped teaching operation;
A robot teaching system comprising: return control means for performing control for returning the robot from the current position coordinate B to the position coordinate A when the teaching operation is resumed.   The robot teaching system according to claim 1, wherein the teaching operation terminal includes an enable switch that stops the teaching operation of the robot by turning off a servo.   3. The robot teaching system according to claim 2, wherein the enable switch causes the robot to perform an emergency stop by an emergency stop button provided separately from the enable switch.   The robot teaching system according to any one of claims 1 to 3, wherein the teaching operation terminal includes display means for displaying the position coordinates A and the current position coordinates B. The teaching operation terminal includes an axis selection means for selecting any one or two or more axes among a plurality of axes constituting the position coordinates A and the current position coordinates B,
5. The robot teaching system according to claim 1, wherein the return control means performs control to return and move the robot about the axis selected by the axis selection means.   The robot teaching system according to claim 1, wherein the position coordinate A is a coordinate of a final position in a state where the servo of the controller is on. In a robot teaching method for teaching an operation to a robot having a drive axis that is servo-controlled using a teaching operation terminal,
A setting step for setting the target position coordinates C of the robot;
A moving step of moving the robot toward the target position coordinates C;
In the course of the movement step, a robot position storage step for storing the position coordinates of the robot at predetermined time intervals;
When the teaching operation of the robot stops during the teaching operation, the position coordinate A immediately before the stopping of the teaching operation of the robot among the position coordinates stored in the robot position storing step is obtained. A stop position storing step for storing;
Storing a current position coordinate B of the robot after the servo control is turned off;
A robot teaching method comprising: a return control step of performing a control of returning the current coordinate from the current position B to the position A when the teaching operation is resumed. The teaching operation terminal includes display means for displaying the position coordinates A and the current position coordinates B;
Axis selection means for selecting any one or two or more of the plurality of axes constituting the position coordinates A and the current position coordinates B, and
A coordinate display step of displaying the position coordinates A and the current position coordinates B for each constituent axis on the display means;
An axis selection step of selecting any one or two or more axes among the plurality of axes constituting the position coordinates A and the current position coordinates B;
The robot teaching method according to claim 7 , wherein the return control step performs a control to return the robot with respect to the axis selected in the axis selection step.