JP2014097560A - Robot controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that a changing operation of jog feeding speed becomes necessary again in order to simply return the jog feeding speed to an original setting value when the jog feeding speed is changed once and it is complicated.SOLUTION: A robot controller RC which performs jog feeding of a robot on the basis of a setting value of jog feeding speed is provided with a CPU 15 as speed control means. When a rotation operation signal Td including a rotation amount and a rotation direction is input from a teach pendant TP having a jog dial 13, the CPU 15 calculates a jog feeding speed change value according to rotational speed on the basis of the rotation operation signal Td, and changes the jog feeding speed by adding and subtracting the calculated jog feeding speed change value in addition and subtraction directions corresponding to the rotation direction. When input of the rotation operation signal is released, the jog feeding speed is returned to an original setting value by setting the jog feeding speed change value to zero. Temporary change of the jog feeding speed can be realized by simple operations.

Description

  The present invention relates to an industrial robot control apparatus, and more particularly to a jog feed operation for manually moving a work tool attached to a robot.

  When processing operations such as arc welding and spot welding are realized by a robot, a method called teaching playback is generally adopted. In the teaching playback method, a work is set at a predetermined position, and the teaching data that teaches the robot's operation with respect to the work is created in a state where the relative positional relationship between the robot and the work is constrained. This is a method in which the same kind of work is continuously processed by repeatedly reproducing the teaching data (see, for example, Patent Documents 1 and 2).

  FIG. 6 is a general configuration diagram of a robot control system 60 employing a teaching playback method. In the figure, a robot 61 includes a work tool T for machining a workpiece W at the tip of an arm 62. The teach pendant 63 is a portable operation device for an operator to teach the operation of the robot 61 with respect to the workpiece W. On the surface of the teach pendant 63, a direction instruction key 64 for moving the work tool T, a speed switching key. 66 etc. are equipped. As shown in the figure, the direction instruction key 64 is generally provided with a plurality of buttons corresponding to the directions of the coordinate system (± X, ± Y, ± Z, etc.). For example, when the work tool T is moved in the base coordinate system which is one of the reference coordinate systems, when the X + of the direction instruction key 64 is pressed, the work tool T is moved in the X + direction of the base coordinate system. Note that an operation in which the operator manually moves the work tool T is often referred to as jog feed or manual operation, but is hereinafter referred to as jog feed.

  The speed switching key 66 is a key for changing the speed at which the work tool T is moved (hereinafter referred to as jog feed speed). Generally, a speed level consisting of several stages is determined in advance, and an operator sets a jog feed speed by selecting a desired speed level.

More specifically, after the operator sets the jog feed speed with the speed switching key 66, the operator moves the work tool T to a desired position by operating the direction instruction key 64 to perform the machining work. Teach work route. Then, the position and orientation coordinate values of the work tool T at the teaching point on the work path are stored in the robot control device 65 as teaching data.

  As described above, when jog feed is performed, it is necessary to select a jog feed speed and to select and press a desired key from a plurality of direction instruction keys 64, which is complicated. For the purpose of reducing this complexity, Patent Document 2 proposes a technique in which a jog dial is provided on the teach pendant 63 and the work tool T can be jog-fed using this jog dial. In Patent Document 2, the movement direction of the work tool T is made to correspond to the rotation direction of the jog dial, and the movement amount of the work tool T is determined according to the rotation amount. Further, by rotating the jog dial while pushing it, the jog feed speed can be changed according to the amount of rotation.

JP-A-6-278066 JP 2001-269883 A

  In the teaching scene, there is a case where the jog feed speed is temporarily increased or decreased from the current set value and returned to the original set value after the change. In Patent Document 1 described above, once the jog feed speed is changed, the jog feed speed changing operation is required again in order to easily return to the original set value. In Patent Document 2, although the operability is improved by enabling the speed change operation and the jog feed operation only with the jog dial, as in Patent Document 1, once the jog feed speed is changed, the original setting is obtained. In order to return to the value, it is necessary to change the jog feed speed again.

  Therefore, an object of the present invention is to provide a robot control device that can realize temporary change of the jog feed speed by a simple operation.

In order to solve the above-described problems, the invention of claim 1
In the robot control device that jogs the robot based on the predetermined value of the jog feed speed,
When a rotation operation signal including the rotation amount of the rotation operation means is input from an operation unit having a rotation operation means, the jog feed speed is changed from the predetermined value based on the rotation operation signal, and the rotation operation signal A robot control device comprising speed control means for returning the jog feed speed to the predetermined value when the input is released.

  According to a second aspect of the present invention, the speed control means calculates a rotation speed of the rotation operation means based on the rotation amount while the rotation operation signal is input, and a jog feed speed corresponding to the rotation speed. 2. The robot control apparatus according to claim 1, wherein a change value is calculated and the jog feed speed is changed based on the jog feed speed change value.

  According to a third aspect of the present invention, when a rotation direction is input from the operation unit in addition to the rotation amount, a jog feed speed change value in an addition / subtraction direction corresponding to the rotation direction is calculated. 2. The robot control device according to 2.

  The invention according to claim 4 is characterized in that the jog feed speed change value is calculated within a range not exceeding a predetermined speed change rate allowable value for a predetermined period after the input of the rotation operation signal is detected. The robot control device according to claim 2 or claim 3.

  According to the present invention, the jog feed speed can be changed by a simple operation, and can be returned to the original set value without performing a special operation. That is, operability can be improved.

It is a block diagram of the configuration of an arc welding robot to which the present invention is applied. It is a general-view figure of a teach pendant. It is a functional block diagram of a teach pendant and a robot control device. It is a figure which shows an example of a jog feed speed change value calculation table. It is a figure for demonstrating a mode that a jog feed speed is changed from a predetermined value. It is a general block diagram of the robot control system which employ | adopted the teaching playback system.

[Embodiment 1]
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the invention will be described based on examples with reference to the drawings.

  FIG. 1 is a system configuration diagram when a robot control device RC according to the present invention is applied to an arc welding robot system 101. As shown in the figure, the arc welding robot system 101 controls the operation of a robot R having a wire feed motor WM for feeding a welding wire 1, a teach pendant TP, which is a portable teaching operation device, and a robot R. It consists of a robot controller RC and a welding power source WP. The teach pendant TP is provided with a jog dial 13 as a rotation operation means and a rotary encoder (not shown) for detecting the rotation direction and the rotation amount of the jog dial 13. The attachment position of the jog dial 13 may be anywhere as long as it is easy for the operator to operate. However, in this embodiment, as shown in FIG. 2, the right hand holding part 41 and the left hand holding part 42 of the teach pendant TP are respectively both hands. When gripped, the jog dial 13 is attached in such a range that it can be operated by the thumb of the right hand and the rotation center axis of the jog dial 13 perpendicularly intersects the side surface of the teach pendant TP.

  Returning to FIG. 1, the robot controller RC outputs an operation control signal Mc for controlling the operation of the servo motors arranged on the robot R based on the operation signal Td from the teach pendant TP, or welding. A welding control signal Wc (a welding start signal, a gas output signal, a feed control signal, a welding voltage setting signal, etc.) is output to the power source WP. The welding power source WP inputs the above various signals, supplies the welding voltage Vw and the welding current Iw, outputs a shield gas by controlling a solenoid valve provided in a gas cylinder (not shown), and supplies a feed control signal Fc. For example, the wire feed motor WM is driven to rotate. The robot R mounts the wire feed motor WM, the welding torch 4 and the like, and moves the tip position of the welding torch 4 according to the operation signal Td. The welding wire 1 is fed through a welding torch 4 by a wire feeding motor WM, and an arc 3 is generated between the workpiece 2 as a work object and welding is performed.

  The operation signal Td includes rotation operation information (rotation direction and rotation amount) of the jog dial 13. Although details will be described later, when the jog dial 13 is rotated, the robot control device RC corresponds to the rotation direction with a change amount predetermined for each unit (one scale) of the detected rotation amount. Increase or decrease the jog feed speed in the direction. In the present embodiment, the jog dial 13 is set to decrease the jog feed speed when rotated to the near side and increase the jog feed speed when rotated to the opposite side. Yes, it can be changed by changing the setting.

  FIG. 3 is a functional block diagram of the arc welding robot system 101 according to the present invention. On the teach pendant TP, a keyboard 11 including a speed switching key 11a, a jog dial 13 as a rotation operation means, a rotary encoder 14 for detecting the rotation direction and the rotation amount of the jog dial 13, an operation menu, a guide message, and the like are displayed. A communication interface unit 12 for communicating with the display 18 and the robot controller RC is provided.

  The speed switching key 11a described above is a key for changing the jog feed speed. Like the prior art, a speed level consisting of several stages is determined in advance, and the operator selects a desired speed level. To set the jog feed speed.

  The teach pendant TP includes a CPU 15, a ROM 16 and a RAM 17. The CPU 15 is a central processing unit. The ROM 16 stores various control programs (input monitoring unit 16a and display control unit 16b) that are read and executed by the CPU 15 and control constants thereof. The RAM 17 is used as a working area for the CPU 15 and temporarily stores data being calculated. Note that the above-described units are connected via a bus 19.

  The input monitoring unit 16a read and executed by the CPU 15 monitors inputs from the keyboard 11 and the jog dial 13, and communicates various operation signals Td including detection signals detected by the rotary encoder 14 based on the monitoring results. Notification is made to the robot controller RC via the interface unit 12. The display control unit 16b displays various information such as the currently set jog feed speed on the liquid crystal display 18 in addition to the operation menu and the guide message.

  Here, the jog dial 13 and the rotary encoder 14 will be described. The jog dial 13 is provided with a scale (notch) that is a unit of rotation and is provided for each predetermined rotation angle. When the jog dial 13 is rotated, the rotary encoder 14 detects a rotation direction and a rotation amount, and transmits a signal indicating which direction the jog dial 13 has been operated in what direction to the robot controller RC.

  The jog dial 13 is normally used as a selector for moving and selecting between items such as operation menus and setting parameters displayed on the liquid crystal display 18. However, when the robot R performs jog feed, It functions as a jog feed speed changing operation means. That is, when the jog dial 13 is rotated when jogging the robot R, the input monitoring unit 16a detects the detection signal of the rotary encoder 14 and outputs it to the robot controller RC as the operation signal Td. As a result, the jog feed speed is changed.

  The robot controller RC controls the robot R so that arc welding is automatically performed on the workpiece 2. The robot control device RC includes the CPU 21, ROM 22, RAM 23, hard disk 25, drive command unit 27, and communication interface unit 24. The ROM 22 stores various control programs (interpretation execution unit 22a, jog feed speed calculation unit 22b, welding command generation unit 22c) and control constants for executing control of the robot R. Details of the various control programs will be described later. The RAM 23 is used as a working area for the CPU 21 and temporarily stores data being calculated. The welding interface unit 26 outputs a welding control signal Wc to the welding power source WP. The welding power source WP outputs a feed control signal Fc for the welding wire 1 to the wire feed motor WM. The drive command unit 27 outputs an operation control signal Mc for controlling the operation of a plurality of servo motors arranged in the robot R based on the operation signal Td from the teach pendant TP. Note that the above-described units are connected via a bus 29.

  The hard disk 25 stores a jog feed speed change value calculation table in addition to teaching data describing the work of the robot R and various control variables. The jog feed speed change value calculation table is a table in which the correspondence between the rotation speed of the jog dial 13 and the jog feed speed change value is defined as shown in FIG. Although details will be described later, in the present invention, the jog feed speed is temporarily changed using this table. In the present embodiment, a hard disk is employed as the storage means, but the present invention is not limited to the hard disk, and other storage devices such as a memory card may be employed.

  Hereinafter, configurations of the interpretation execution unit 22a, the jog feed speed calculation unit 22b, and the welding command generation unit 22c that are read and executed by the CPU 21 serving as a speed control unit will be described.

  The interpretation execution unit 22a determines whether or not the jog feed speed change process is required based on the detection signal of the rotary encoder 14 input from the teach pendant TP. The change value is calculated and notified to the jog feed speed calculation unit 22b.

  The jog feed speed calculation unit 22b calculates the jog feed speed based on the jog feed speed change value notified from the interpretation execution unit 22a, and outputs it to the drive command unit 27 described above.

  The welding command generator 22c generates a welding control signal Wc for performing arc welding processing. The welding control signal Wc is output to the welding power source WP via the welding interface unit 26, and a feeding control signal Fc for feeding the welding wire is outputted to the wire feeding motor WM.

  Hereinafter, the operation of the present embodiment will be described. In order to simplify the explanation, it is assumed that a jog feed operation is currently being executed, and the jog feed speed is set to a predetermined value (a constant value) by the speed switching key 11a.

(1. Notification of operation results)
When the jog dial 13 is rotated, the input monitoring unit 16a of the teach pendant TP outputs the detection signal (the rotation direction and the rotation amount of the jog dial 13) of the rotary encoder 14 to the robot controller RC. This detection signal is notified to the interpretation execution unit 22a every predetermined detection cycle.

(2. Interpretation of operation results)
The interpretation execution unit 22a determines whether a jog feed operation is performed when the detection signal is input. In other words, it is determined whether or not the jog dial 13 has been rotated while the jog feed operation is being performed (that is, whether or not the jog feed speed changing operation has been performed). If it is determined that the jog feed speed changing operation has been performed, the rotation speed of the jog dial 13 is calculated based on the rotation amount included in the detection signal. The rotation speed may be calculated by a simple method of calculating based on the rotation amount per unit time. Next, the calculated rotation speed is input to the jog feed speed change value calculation table described above to calculate the jog feed speed change value. Further, a sign +/− (plus / minus) corresponding to the rotation direction is assigned to the jog feed speed change value and notified to the jog feed speed calculation unit 22b.

  FIG. 4 is a diagram illustrating an example of a jog feed speed change value calculation table. As shown in the figure, the correspondence between the rotation speed of the jog dial 13 and the jog feed speed change value is defined in a table format. The interpretation execution unit 22a inputs the calculated rotation speed of the jog dial 13 to the jog feed speed change value calculation table to calculate the jog feed speed change value. The jog feed speed change value calculation table is an example for calculating the change value of the jog feed speed, and needless to say, the jog feed speed change value calculation table may be configured to calculate using a predetermined function instead of the table format.

(3. Calculation of jog feed speed)
The jog feed speed calculation unit 22 b calculates a new jog feed speed by increasing or decreasing the jog feed speed change value notified from the interpretation execution unit 22 a from a predetermined value of the jog feed speed, and notifies the drive command unit 27 of the new jog feed speed. As a result, the jog feed speed corresponding to the rotation operation of the jog dial 13 is changed. That is, the rotation operation of the jog dial 13 is detected at every predetermined detection cycle, and after the jog feed speed change value is calculated according to the operation result such as the rotation amount and the rotation direction, the jog feed speed is increased or decreased from the predetermined value. . When the rotation operation of the jog dial 13 is stopped, the jog feed speed change value becomes 0 (zero), so that the jog feed speed returns to the predetermined value. That is, during jog feed, the jog feed speed can be temporarily adjusted only by rotating the jog dial 13.

  FIG. 5 is a diagram for explaining how the jog feed speed is changed from a predetermined value. In the figure, a solid line Sk indicates a predetermined value set by the operator using the speed switching key 11a. A dotted line Sf indicates the jog feed speed change value calculated by the interpretation execution unit 22a according to the rotation operation of the jog dial 13. An alternate long and short dash line Sj indicates the jog feed speed after the change in which the jog feed speed calculation unit 22b adds or subtracts the jog feed speed change value from the predetermined value. t0 to t4 indicate times.

(1. Period from time t0 to t1)
This period indicates a state in which the jog feed operation is started from the state where the jog feed operation is not performed and the jog feed speed reaches a predetermined value set by the speed switching key 11a.

(2. Period of time t1 to t2)
This period shows a state where the jog feed operation is continued in a state where the jog dial 13 is not rotated. The jog feed speed remains constant at a predetermined value.

(3. Period of time t2 to t3)
This period shows a state in which the jog dial 13 is rotated in the + direction during the jog feed operation. During this period, the speed corresponding to the rotational speed of the jog dial 13 is added to the predetermined value of the jog feed speed in real time.

(4. Period from time t3 to t4)
This period shows a state in which the jog dial 13 is rotated in the negative direction during the jog feed operation. During this period, the speed corresponding to the rotational speed of the jog dial 13 is subtracted in real time from the predetermined value of the jog feed speed.

(5. Period of time t4 to t5)
Time t4 is the time when the rotation operation of the jog dial 13 is stopped. Therefore, since the jog feed speed returns to the predetermined value, the jog feed speed during the period from time t4 to time t5 remains constant at the predetermined value.

  Thus, it can be seen that the jog feed speed is changed as a result of adding / subtracting the rotational speed of the jog dial 13 to / from the predetermined value set by the speed switching key 11a.

  As described above, according to the present invention, the jog feed speed can be changed by a simple operation and can be returned to the original set value without performing a special operation. That is, operability can be improved.

  In the above-described embodiment, it is further preferable that the jog feed speed change value is calculated within a range that does not exceed a predetermined speed change rate allowable value for a predetermined period after the rotation operation of the jog dial 13 is detected. For example, when the jog feed speed (predetermined value) set by the speed switching key 11a is 100 cm / min, the predetermined period is 1 second, and the speed change rate allowable value is set to 20%, the jog dial 13 Is rotated in the + direction (plus direction), the following processing is performed. That is, no matter how fast the jog dial 13 is rotated for one second after detecting the rotation operation, the speed change rate allowable value of 20% is not exceeded (the jog feed speed after the change is 100 cm). (Not exceeding 120 cm / min, multiplied by 20% / min). This can prevent a rapid change in speed.

DESCRIPTION OF SYMBOLS 1 Welding wire 2 Workpiece | work 3 Arc 4 Welding torch 11 Keyboard 11a Speed switching key 12 Communication interface part 13 Jog dial 14 Rotary encoder 15 CPU
16a Input monitoring unit 16b Display control unit 18 Liquid crystal display 19 Bus 21 CPU
22a Interpretation execution unit 22b Jog feed speed calculation unit 22c Welding command generation unit 24 Communication interface unit 25 Hard disk 26 Welding interface unit 27 Drive command unit 29 Bus 41 Right hand gripping unit 42 Left hand gripping unit 60 Robot control system 61 Robot 62 Arm 63 Teach pendant 64 Direction instruction key 65 Robot control device 66 Speed switching key 101 Arc welding robot Fc Feed control signal Iw Welding current Mc Operation control signal R Robot RC Robot control device Sf Dotted line Sj Dash-dot line Sk Solid line T Work tool Td Operation signal TP Teach pendant Vw Welding voltage W Work Wc Welding control signal WM Wire feed motor WP Welding power source

Claims (4)

In the robot control device that jogs the robot based on the predetermined value of the jog feed speed,
When a rotation operation signal including the rotation amount of the rotation operation means is input from an operation unit having a rotation operation means, the jog feed speed is changed from the predetermined value based on the rotation operation signal, and the rotation operation signal A robot control apparatus comprising speed control means for returning the jog feed speed to the predetermined value when the input is released.   The speed control means calculates a rotation speed of the rotation operation means based on the rotation amount while the rotation operation signal is input, and calculates a jog feed speed change value corresponding to the rotation speed. The robot control apparatus according to claim 1, wherein the jog feed speed is changed based on a jog feed speed change value.   The robot control apparatus according to claim 2, wherein when a rotation direction is input from the operation unit in addition to the rotation amount, a jog feed speed change value in an addition / subtraction direction corresponding to the rotation direction is calculated.   The jog feed speed change value is calculated within a range not exceeding a predetermined speed change rate allowable value for a predetermined period after the input of the rotation operation signal is detected. The robot control device described.

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