JPH07290386A - Control method for industrial robot - Google Patents

Abstract

PURPOSE:To make it possible to conduct teaching while an operator is unconscious of the inoperable region by generating a point near the boundary of the operable range corresponding to the arm position when the arm position beyond the operable range is to be taught, and using the generated point as a teaching point. CONSTITUTION:The operable range of an arm is stored. When an operator continuously pushes a Y+ switch starting from P1, the arm changes the direction toward P2 at P6 immediately before going out of the stored operable range and advances by the prescribed distance. When the operator continuously pushes the Y+ switch thereafter, the arm advances to P7 so far as the arm is located within the operable range. When the operator takes a simple action, the system generates the optimum teaching point, and the operability is high.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of controlling an industrial robot capable of teaching.

[0002]

2. Description of the Related Art Normally, when teaching an operation of an assembly robot, it is necessary to actually move the robot to teach (store) the position. Conventionally, in order to move a robot, as shown in JP-A-57-83390, the forward / reverse switch on the operation panel of the robot is used to move the robot in the coordinate axis direction of the orthogonal coordinate system provided on the robot. The position was taught and the position was taught. : Alternatively, move each joint directly with the forward / reverse switch on the operation panel to align the robot,
Teaching the position was also performed.

[0003]

However, in the method of the conventional example, since the work area of the robot becomes circular, the robot is moved in the boundary area in only one direction of the coordinate axes in the orthogonal coordinate system. Since it becomes impossible to move, it is necessary to move while switching the coordinate axes,
The disadvantage is that the operator becomes complicated.

Further, in the case of the method of the conventional example, in order for an operator who teaches the position to move the robot to an arbitrary point, it is necessary to move each joint apart at the coordinates (joint coordinates) peculiar to the robot. Matching has the drawback of requiring skill and a great deal of time. Further, a teaching method having both functions of and can be considered in order to make up for the drawbacks of the teaching in the orthogonal coordinate system, but there is a disadvantage that the switching of both teaching methods is required and the operation becomes more complicated.

On the other hand, since the rotation angle of the arm of the robot can be freely set, a detector for detecting the rotation angle is conventionally provided so as not to damage the arm. This detector has been a factor in increasing costs.

[0006]

SUMMARY OF THE INVENTION The present invention has been made for the purpose of solving the above problems, and when an industrial robot having a limited operable range is taught, the operator is It is to propose a control method of an industrial robot that enables teaching without being aware of the inoperable area.

A method of controlling an industrial robot according to the present invention for achieving the above object stores a movable range of an arm in a method of controlling an industrial robot having an arm having a limited operating range, When the arm position is to be taught beyond the operable range, a point near the boundary of the operable range, which corresponds to the arm position, is generated, and the generated point is used as a teaching point. Characterize.

A further object of the present invention is to propose a control method capable of correcting the teaching point to the operable position when teaching the inoperable range. The configuration of the present invention for such a purpose is to detect the changing direction of the arm position before and after the teaching time point, and set the point on the boundary line of the working range in the direction orthogonal to the changing direction as the generated point. It is characterized by doing.

A further object of the present invention is to propose a method for controlling an industrial robot, which can suggest a candidate for a preferable teaching point when trying to teach an inoperable range. A further object of the present invention is to propose a method of controlling an industrial robot, which informs the operator when it is impossible to generate a point near the boundary. A further object of the invention is to propose a method for controlling an industrial robot, which is capable of teaching without the need for a detector for detecting the amount of arm rotation.

To this end, the method of controlling an industrial robot according to the present invention converts a movement command represented by a Cartesian coordinate system into a movement angle of each joint in order to move the arm of the industrial robot. In a control method for controlling the rotation amount of the arm, it is determined whether the movement command is generated by a teaching operation, and if it is generated by an operation other than the teaching operation, the rotation amount of the arm is optimized and output. Then
When it is generated by a teaching operation, the rotation amount of the arm is output without optimization.

[0011]

Embodiments will be described in detail below with reference to embodiments of the present invention. <First Embodiment> FIG. 3 is a perspective view of an apparatus including an assembling robot according to a first embodiment of the present invention.

In FIG. 3, an assembling robot 5 is provided with a parts supply unit (10, 10) for supplying parts to the robot 5.
It is fixed to the floor together with 11). The robot 5 of this embodiment is a so-called horizontal articulated robot having four degrees of freedom, and two horizontal arms 300a and 300b are driven by motors 5a and 5b. The motor 5c moves the arm tip up and down (Z axis), and the motor 5d rotates the arm tip (S axis). It should be noted that six hands are attached to the wrist of the robot 5c, and the fingers can be driven by the three motors 6a, 6b, 6c to grip the article. 5a, 5b,
The motors 5c, 5d, 6a, 6b, 6c are the control device 1
It operates according to the operation stored in advance.

The position where the robot 5 is placed is as follows:
The pallets 9a and 9b on the second article supply units 10 and 11 are in a positional relationship capable of gripping the articles. Further, 15 is a detachable portion of the hand 6, which is detached by opening a clamper (not shown) in response to a command from the control device 1. Reference numeral 7 denotes a hand holding base. By holding a plurality of hands on the holding base 7, the robot can automatically attach any hand on the holding base, and the hand is currently attached to the wrist. It is also possible to automatically place and remove the existing hand on the hand holding table 7. Further, 8 is an assembling stage, which can be provided with a guide assist function as needed at a place for assembling the articles grasped by the robot.
It becomes possible to control by placing a drive source on the assembling stage and connecting it to the controller 1 with a cable.

The above-mentioned control device 1 is an assembly robot control device for controlling the entire assembly work. The first control device is connected to the robot by a cable 16 and is capable of controlling actuators such as the robot and hand and inputting a sensor (not shown). Control device 1
Has a CRT and a keyboard 4, which enables input / output to / from the control device. Furthermore, the operation panel 2 dedicated to teaching
Can be connected to the control device 1. CRT
3. The movement position of the robot 5 can be taught in advance via the control device 1 using the keyboard 4. Also, the teaching can be performed by using the operation panel 2 dedicated to teaching.

Here, in the orthogonal coordinate system 14 for teaching, which is set in the robot 5, the horizontal plane is represented by the X axis and the Y axis, the rotation of the tip portion is represented by the S axis, and the upper and lower sides are represented by the Z axis. FIG. 4 is a block diagram showing the entire control apparatus of the embodiment of the present invention. 5
Reference numeral 0 is a CPU, 51 is a ROM, and a command interpretation program for executing an assembly operation, a teaching operation support program for teaching the position of the robot, and the like are stored in advance in this ROM. Details of this program will be described later.

Reference numeral 52 denotes a RAM, in which a group of robot hand operation commands input from the keyboard 4,
Also, the teaching position data obtained by actually moving the robot 5, coordinate conversion data for expressing the horizontal articulated robot as an orthogonal coordinate system, and the like are stored. 54
Is a local bus of the CPU 50, and the ROM 51, the RAM 52 and the interface 53 are connected to the local bus. The data in the RAM 52 can be displayed on the CRT 3 and can be input and deleted using the keyboard 4. Further, the position teaching operation of this embodiment can be input from the operation panel 2.

Reference numerals 12 and 13 are control units of the article supply unit,
It is possible to exchange information with the CPU 50 through the interface 63. Reference numeral 64 denotes an interface for communicating with an external computer or the like, which sends information in the robot control device to the outside through a signal line 65 and inputs information from the outside. For example, it is possible to calculate the timing of automatic delivery of pallets by communicating with an unmanned warehouse management computer.

Reference numeral 57 is a CPU 50 and a robot operation unit 61,
A common bus connecting the hand operating unit 62 and the shared memory 60, and a multibus is used in this embodiment. CPU50
Then, the operation instruction is interpreted and executed, and the generated instruction code is set in the shared memory 60. The robot operation unit 61 or the hand operation unit 62 receives the instruction code generated by the CPU 50 and performs an actual operation. When the operation is completed, the operation unit writes an operation end signal on the shared memory 60.

Robot operating unit 61, hand operating unit 62
When an instruction code is written in the shared memory 60, the instruction code is read out and the operation processing according to the code is performed, and each device, that is, the motor 5a to 5d for each motor robot operation, and the hand operation Motors 6a-6
Control the rotation stop of c. Reference numeral 55 is a known magnetic external storage means, such as a floppy disk drive, which is passed through the interface 53 to allow the robot
The keyboard 4 displays hand operation instruction groups and teaching position data.
It is possible to memorize by the operation of. On the contrary, by bringing the already stored floppy disk, it is possible to store the operation command group and the teaching position data in a predetermined area in the RAM 52.

FIG. 5 shows a teaching operation panel 2 used to teach the position of the robot 5. Reference numeral 101 denotes a display unit of the LCD, which displays the teaching position of the robot. On the display screen 101, two columns of numbers are arranged side by side, and the column marked with 0 at the left end represents the current robot position as a Cartesian coordinate system X, Y, Z, S. The column marked 1 at the left end shows the teaching position data of the Cartesian coordinate system X, Y, Z, S registered in the RAM 52.

The switches 102 to 109 are switches for driving the robot according to a rectangular coordinate system. 102
Is a switch for inching so that the coordinate value increases in the X-axis direction, and 103 is a switch for inching so that the coordinate value decreases in the X-axis direction. It should be noted that Y, Z, and S are each provided with a switch for inching. 111 is a switch for changing the speed at which the robot is moved, 110 is the current position of the moved robot in RA
This is a switch registered in M52.

FIG. 1 is a diagram showing the position of the horizontal plane (X, Y axes) of the robot. FIG. 6 is a flowchart showing a moving process for teaching performed by the CPU 50 based on a program written in the ROM 52. Hereinafter, the procedure of the operation command of the robot for teaching according to the present embodiment will be described. In FIG. 1, 9a is a pallet 9a on the component supply unit 10 (see FIG.
3), 9b indicates a pallet 9b (see FIG. 3) on the component supply unit 11, and 8 indicates an assembly stage of FIG.

Further, P ₁₁ , P ₁₃ , P ₁₂ , and P ₁₄ are respectively
The intersection of the maximum movement range (indicated by a circle) of the robot arm and each coordinate axis is shown. _{Thus, P 11 = (0, R} max) P 13 = (R max, 0) P 12 = (0, -R max) P 14 = - a (R _max, 0). When Rmax is the maximum diameter of the operating region and Rmin is the minimum diameter, the maximum movement range is represented by X ² + Y ² ≤R _max ² (1), and the minimum movement range is X ² + Y ² ≥R _min ² ... It is represented by (2). The feature of the present embodiment is that if the inching operation for teaching tries to proceed to a region other than the region defined by the above two equations, the coordinate point is forcibly changed. The outline will be described with reference to FIG.

In FIG. 1, the purpose of moving the article (at the point P ₁ to be taught) grasped by the robot hand from the first pallet 9a to the assembly stage 8 (at the point P ₅ to be taught). Then, when trying to teach those positions, as one route, by continuing to push the switch Y + 104 from P _{1 to} P ₄ , inching in the Y-axis direction proceeds, and then by pushing the switch X + 102. P ₄
A course in which the direction is changed to the X-axis direction and inching is performed up to P ₅ can be considered. Such courses are
The operability is high because it can be obtained by simply pressing the switch Y + 104 or the switch X + 102. However, as shown in FIG. 1, on the course of P ₁ → P ₄ , if the inching is simply performed in the Y-axis direction, the teaching point will exceed the minimum range. Therefore, in the past, the operator has used P1 → P2 → P
I chose the course 3 → P4. In this conventional method, a plurality of teaching points have to be taught along the arc in the course of P2 → P3, and the operation is complicated. In the teaching method of the present embodiment, when the teaching point tries to exceed the operable range, the system changes the teaching point so that the teaching point falls within the operable range without the operator changing the switch operation. To do.

That is, in FIG. 1, when the operator starts from P ₁ and continues to press the Y + switch, the direction is changed to the direction P ₆ just before trying to go out of the operable range (P ₂ ), and the predetermined distance is advanced, After that, even if you continue to press the Y + switch,
As long as it is within the operable range, it will proceed to P ₇ as it is. In this way, even if the operator performs a simple operation, the system will generate an optimum teaching point, so the operability is high.

FIG. 6 shows how to generate this optimum teaching point.
3 is a flowchart of the control procedure of FIG. The control hand of this FIG.
The order is the control procedure corresponding to the operation of the Y + key switch.
It When the Y + switch is operated, step S201
And the current position (X_i-1 , Y _i-1 ) Is updated. X_i= X_i-1 (3) Y_i= Y_i-1+ ΔY (4) In step S208, the operation of pressing the Y + key is in the Y direction.
Limit R_maxWhether it is something that is going to exceed Y_i> R_max ... (5) to judge. Y_i> R_maxIs the teaching
Point is P₁₁It was when I reached the vicinity of. Limit R in Y direction
_maxWhen the operation of Y + key to try to exceed the
If it is impossible to correct the teaching point, step S2
09, "Area over", "-Y, + X, -X
It is possible to move in any direction ”and prompt the operator to call.

When the teaching point does not reach the vicinity of P ₁₁ , NO is determined in step S208, so step S2
Proceeding to 02, it is determined according to the equation (1) whether or not the coordinate value in step S201 exceeds the maximum radius Rmax of the operation area of the robot. If it exceeds, in step S203, the X coordinate value of the teaching point is corrected from X _i to X ′ _i based on the following equation so that it is on the boundary of the operation area.

X ′ _i = (R ² _max −Y ² _i ) ^1/2 × SGN (X _i ) (6) In step S207, the corrected X ′ _i is set as the teaching point X.
Output as coordinates. On the other hand, if it is determined in step S202 that the position to be taught does not exceed Rmax, then in step S204 it is compared whether the position is less than the minimum diameter Rmin according to equation (2).

If it is less than the minimum diameter Rmin, it means that the vehicle is going out of the movable range.
In step 5, as in step S203, only the X coordinate is calculated according to equation (6) so that it is on the boundary of the minimum movable range. On the other hand, if NO in step S204, that is, if the teaching point falls between the maximum range and the minimum range, the value in step S201 remains unchanged, and after steps S203, S205, and S206. In step S207, new X and Y coordinates are output to the robot motion unit.

By continuing this control procedure (FIG. 6) while the Y + 104 switch in FIG. 4 is being pressed, the pallet positions P1 to P2 in FIG. 1 are straight lines, P2 to P3 are arcs, and P3 to P3.
P4 is a straight line and the robot rotates. During this time, the worker
All you have to do is move it in the Y-axis direction.
The control procedure of FIG. 6 is performed when the Y + key is pressed. The present invention is, of course, in accordance with the switch 10 of FIG.
It is applicable corresponding to each of 2 to 109. These keys can be dealt with by slightly changing the control procedure of FIG.

For example, when the Y-key is pressed to move in the minus direction in the Y direction, step S2 in FIG.
Instead of Yi = Yi + ΔYi of 01, Yi = Yi−Δ
If Y is set, the condition of step S208 is set to Y _i <−R _max, and “+ Y, + X, −X movable” is displayed on the display of step S209. Also in the X direction, it can be realized by exchanging the X and Y displays in the same manner as in FIG. 6 and the minus movement in the Y direction. In this way, it is also possible to move in the direction of the horizontal plane.

Similarly, the present invention can be applied to a cylindrical robot having a turning axis. Thus, according to the first embodiment, it is possible to eliminate the troublesomeness in which the operator uses the orthogonal movement and the joint movement for the teaching work of the robot having joints and to shorten the teaching work time. Specific effects such as easy prevention of collision accidents can be obtained.

<Second Embodiment> In the first embodiment, when the work area includes an area where the robot arm cannot operate, the operator teaches the area where the robot arm cannot operate. However, it was a control device that automatically generates teaching points that avoid the impossible area. The control device of the second embodiment described below is also related to the teaching. The background of the control device of the second embodiment is as follows.

Normally, the arm (particularly, the tip shaft) of the robot apparatus can be freely rotated by a human operation when the power is cut off. Therefore, the robot controller always remembers the position of the arm axis no matter how much it rotates. A detector for detecting the rotation of the arm shaft is specially required, and the cost of the control device is high.

Further, in the case of the control device which does not have the above-mentioned detector at all, it is not easy to use when a person teaches the position where the robot assembles the article, and it takes a lot of time for the teaching work, or depending on the case. Has a tip rotation axis of 3
There was a drawback that there was a risk that the article for assembly or the robot itself could be destroyed by rotating it by about 60 degrees. The control device according to the second embodiment determines whether a teaching operation performed by a person or an automatic operation is performed when the position data of the Cartesian coordinate system of the articulated robot is converted into each joint angle information. Thus, the range of movement of the joint angle is changed during automatic driving, and when teaching is operated by a person, the person can judge the condition of the article and continuously move the robot, and the robot can perform unintended actions. This is to prevent it from happening.

The robot system of the second embodiment also has the structure of the articulated robot 5 as shown in FIG. 3, and its control device has the structure of FIG. The teaching panel used in the system of the second embodiment also has the structure shown in FIG. FIG. 2 shows, among the operations of the articulated robot 5, an operation particularly related to the second embodiment in an orthogonal coordinate system.

In FIG. 2, reference numeral 300 indicates a rotation axis of the motor 5c, 301 indicates a rotation center axis of an arm rotated by the motor 5d, 302 indicates a tip position of the hand, and 303 indicates a rotation position of the finger. . In FIG. 2, the robot 5 has three arm positions (201, 201).
02, 203). Reference numeral 201 represents the posture of the robot in the reference state, and the reference direction is the X axis. In the standard posture, each joint angle is zero.

Reference numeral 202 denotes the posture of the robot when it moves to a certain position. The rotation of the motor 5a shown in FIG. 3 causes the first arm 204 to rotate at an angle of θ ₁ , and the rotation of the motor 5b causes the rotation of the second arm 205 to θ _2. The rotation axis of the tip portion 206 is rotated by an angle of θ ₄ by the rotation of the motor 5d. Each of the angles θ _{1 to} θ ₄ is the rotation angle of the joint portion, and is detected by the robot driving unit 61 in FIG. From the rotation angles θ _{1 to} θ _{4 of} this joint, the position data of the orthogonal coordinate system is calculated by the following equation.

X = l ₁ × cos θ ₁ + l ₂ × cos (θ ₁ + θ ₂ ) (7) y = l ₁ × sin θ ₁ + l ₂ × sin (θ ₁ + θ ₂ ) ... (8) S = θ ₁ + θ ₂ + θ ₄ (9) where l ₁ is the length of the first arm 204 and l ₂ is the length of the second arm 205. Further, since the calculation of the equations (7) to (9) is performed in the arm order, the "arm order calculation"
I will call it.

The rotation angles θ _{1 to} θ ₄ of the respective joints are transferred from the robot driving unit 61 via the shared memory 60 to the CPU 50.
Is transmitted to the orthogonal coordinate data (x, y, y) by the ROM 51 including the calculation programs of the above formulas (7) to (9), the RAM 52 including the coordinate conversion data such as the arm lengths of l ₁ and l ₂ , and the CPU 50. S). This Cartesian coordinate data is displayed on the CRT 3 by inputting on the keyboard 4 or the operation panel 2 or R as teaching position data.
It is registered in AM52.

R _max and R _min in FIG. 2 indicate the boundaries of the operation area of the robot, and only the donut-shaped area in FIG. 2 is the area where the robot can move. The formula is as follows. X ² + Y ² = R _max ² (10) X ² + Y ² = R _min ² (11) where R _max = l ₁ + l ₂ (12) R _min = [{l ₁ -l ₂ × cos ( 90−θ _2max )} ² + {l ₂ × sin (90−θ _2max )} ² ] ^1/2 (13) where θ _2max represents the maximum value of the second arm rotation angle of 203. The operating range of the tip rotation angle is −180 degrees <S−θ ₁ −θ ₂ (= θ ₄ ) ≦ 180 degrees.

By inputting from the keyboard 4 or the operation panel 2, etc., arbitrary position data (x,
y, S) is the joint angle data θ _{1 to} θ by the CPU 50.
_It is converted into ₄ and transferred as an operation amount and an operation command to the robot operation unit 61 via the shared memory 60. CPU5
The contents of conversion performed by 0, ROM 51, and RAM 52 are expressed by the following equations.

C ₂ = (x ² + y ² −l ₁ ² −l ₂ ² ) / 2l ₁ · l ₂ (14) S ₂ = (θ ₁ −C ₂ ² ) ^1/2 (15) θ ₂ = Tan ^-1 (S ₂ / C ₂ ) (16) C ₁ = (C ₂ · l ₂ + l ₁ ) x + S ₂ · l ₂ · y (17) S ₁ = (C ₂ · l ₂ + l ₁₎ ) · Y−S ₂ · l ₂ · x (18) θ ₁ = tan ⁻¹ (S ₁ / C ₂ ) (19) θ ₄ = S−θ ₁ −θ ₂ (20) (14)- The calculation of the equation (20) will be referred to as "arm inverse operation".

FIG. 7 shows a processing flow when the CPU 50 of this embodiment moves the robot to a certain position shown in the Cartesian coordinate system. Here, a case will be described in which the operator operates one of the switches 102 to 109 of the operation panel 2 to instruct the robot 5 to move to a new position for a teaching operation. In this case, the current position data of the direct coordinate system is changed and the movement to the new position data is started.

First, in step S301, the arm inverse calculation is executed based on the current position data and the new position data represented by the Cartesian coordinate system and converted into joint angle information. In step S302, it is determined whether or not this operation is a teaching operation. This determination is made based on whether or not the operation panel 2 has been used. That is, in FIG. 4, when the operation panel 2 is operated and a teaching command is input, the command is stored in the RAM 52 with a flag indicating that it is a command via the operation panel. Step S302 sets this flag to the CPU
50 checks and judges. When the "arm inverse calculation" in step S301 is executed by the normal movement command, the flag is not set in the command, and thus NO is determined in step S301.

If it is determined to be a teaching operation, step S3
07, θ ₁ to θ ₄ obtained in step S301
Is output to the robot drive unit. On the other hand, when the determination in step S302 is other than the teaching operation (when the actual automatic assembly operation is performed), steps S303 and S3
In 04 and step S305, θ ₄ is corrected so that the joint angle θ ₄ of the tip rotation axis is within ± 180 degrees.
In step S307, the angle data including the corrected θ ₄ is output to the drive unit of the robot.

Further, when the joint angle information θ _{1 to} θ ₄ has passed to the robot drive unit 61 of FIG. 4, the operation command of step S308 of FIG. 7 is output from the CPU 50 via the shared memory 60, and in response to this. Robot drive is 5a
The robot can be moved to the position of the Cartesian coordinate system by moving each motor of 5d. The present invention described above is
The horizontal articulated robot was taken as an example, but the cylindrical arm robot, Cartesian coordinate robot, or vertical articulated robot that has a swivel axis at the tip of the robot also has the "arm order calculation".
Only the contents of the "arm inverse calculation" are changed, and this device can be easily deployed.

According to the second embodiment, during coordinate conversion, it is determined whether or not a person is in the teaching operation of the robot, and if teaching is in progress, the range of movement of the joint angle is changed. Since it is not performed, it is difficult to break the effector of the object or the robot selected during the teaching work of assembling the object. In addition, since the movement range is changed during the automatic operation of the robot other than the teaching, naturally, for example, the wiring or piping at the tip of the robot is ± 18.
It goes without saying that even if the rotation is allowed only about 0 degrees, it operates without breaking them.

[0049]

As described above, according to the present invention,
It is possible to teach easily without forcing the operator to judge whether or not it is within the movable range. Further, it was possible to enable simple teaching of operation without requiring a detector for detecting the rotation amount of the arm.

[Brief description of drawings]

FIG. 1 is a diagram showing the position of a horizontal plane (X, Y) of a robot for explaining the principle of the first embodiment of the present invention.

FIG. 2 is a diagram showing a model in which the articulated robot is used as position teaching data in an orthogonal coordinate system in order to explain the principle of the second embodiment of the present invention.

FIG. 3 is a perspective view of an apparatus including an assembly robot according to an exemplary embodiment of the present invention.

FIG. 4 is a configuration diagram showing an entire control device according to an embodiment of the present invention.

FIG. 5 is a diagram showing an appearance of a teaching panel for teaching the position of the robot according to the embodiment of the present invention.

FIG. 6 is a flowchart showing a moving process for teaching in the first embodiment of the present invention.

FIG. 7 is a processing flow when the robot of the second embodiment of the present invention moves a robot into a Cartesian coordinate system.

[Explanation of symbols]

 1 Assembly Robot Control Device 2 Teaching Operation Panel 3 CRT 4 Keyboard 5 Robot 5a, 5b, 5c, 5d, 6a, 6b, 6c Motor 6 Hand 7 Hand Holding Table 8 Assembly Stage 9a, 9b Pallet 10 First Part Supply Part 11 Second component supply part 12 First supply part control part 13 Second supply part control part 14 Cartesian coordinate system 16 Cable 50 CPU 51 ROM 52 RAM 56, 63, 64 Interface 54 Local Bus 55 FDD 57 Common Bus 60 Shared memory 61 Robot operating unit 62 Hand operating unit 65 Signal line

Claims (7)

[Claims] 1. A method for controlling an industrial robot having an arm having a limited operating range, wherein an operable range of the arm is stored, and when the arm position is to be taught beyond the operable range. A method for controlling an industrial robot, wherein a point near the boundary of the operating range corresponding to the arm position is generated and the generated point is used as a teaching point. 2. When the teaching point is represented by an orthogonal coordinate system, the changing direction of the arm position before and after the teaching time is detected, and the point on the boundary line of the working range in the direction orthogonal to this changing direction is detected. 2. The method for controlling an industrial robot according to claim 1, wherein the generated points are used. 3. The method of controlling an industrial robot according to claim 1, further comprising instructing an operator of a movable direction when it is impossible to generate a point near the boundary. 4. The method for controlling an industrial robot according to claim 1, wherein when it is impossible to generate a point near the boundary, the fact is notified to the operator. 5. When the position data of the Cartesian coordinate system set at the time of position teaching is within the robot work area, the joint portion of the robot is driven and set so that the robot moves in only one axis direction of the Cartesian coordinate system. When the position data of the Cartesian coordinate system is outside the work area of the robot, the movement position along the boundary of the work area of the robot is calculated so that at least one axis direction of the Cartesian coordinate system can move, and the joint portion of the robot is determined. A method for controlling an industrial robot characterized by driving. 6. A control method for controlling an amount of rotation of the arm by converting a movement command represented by a Cartesian coordinate system into a movement angle of each joint to move the arm of the industrial robot. It is determined whether the command is generated by a teaching operation, and if it is generated by an operation other than the teaching operation, the amount of rotation of the arm is optimized and output, and if it is generated by the teaching operation, the arm rotation is performed. A method for controlling an industrial robot, which is characterized by outputting a momentum without optimization. 7. When the rotation angle of the arm is limited,
7. The optimization is performed by adjusting an angle that is an integral multiple of 360 degrees from the rotation amount of the arm so that the rotation amount of the arm is corrected to fall within a limit. Industrial robot control method.