JPH01287705A - Robot controller - Google Patents

Abstract

PURPOSE:To rapidly and flexibly respond to the change of specification with respect to operation control at a site by performing the execution of sequential progression of the processing of the operation control and step information simultaneously and in parallel with that of the scanning processing of sequence information. CONSTITUTION:The input/output of the ascending/descending of a screw tightening head by the step information, an energizing/de-energizing signal limit switch for an end effector such as the operation of a screw driver, etc., and an internal field sensor such as a screw loose sensor, etc., are set as the one performed indirectly by the readout and write of an internal contact 34 addressed in a RAM. Meanwhile, the information of the contact 34, on which a logical operation by a scanning processing being always applied according to ladder sequence by the sequence information, is inputted and outputted from an input/output interface where the input/output is performed actually. And the operation control of a robot, the sequential progression of the processing of the step information 32, and the scanning processing of the sequence information 36 are executed simultaneously and in parallel. In such a way, it is possible to respond to the change of application at the site.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention particularly relates to a robot control device having a sequence control function in an input/output section for external signals related to robot operation and motion control.

[Background of the invention]

In general, command information such as return to origin, startup, and work start is input as an external specific signal input related to the operation and motion control of industrial robots, and the microcontroller executes judgment processing according to predetermined procedures stored in ROM etc. However, the system recognizes that the command information has been input and starts operating. Now, if we look at the start of work, which is one of the command information of screw tightening robot soto,
Normally, screw tightening work is started simply by inputting this work start signal as a condition for starting work, but depending on the condition of the conveyor or platen, for example, the reliability of screw tightening work may vary depending on the condition of the conveyor or platen. In order to improve performance, a sensor detects whether the placement posture of the workpiece placed on the platen is good or bad, and the logical product of the sensor output signal indicating that the placement posture is OK and the external specific human power signal of the work start command is taken. It may be necessary to start the screw tightening operation.

In this case, in conventional robot control devices of this type,
inputting the two signals separately to the robot control device and changing the processing program in the ROM executed by the microcomputer;
You can either have software perform the logical product of the two signals, or you can use a sequence controller to calculate the logic of the two signals outside the robot control device without changing the processing program executed by the microcomputer. There is a method of calculating the product and inputting the result to the robot control device as a work start command. Changing the processing program in the former case involves changing the microcomputer code in the ROM and requires a software development support device, which is difficult to handle on-site, while the latter use of a sequence controller requires installation space.

If the installation space is limited, installation may become impossible, and both methods have the drawback of being difficult to respond quickly on-site.

[Purpose of the invention]

One object of the present invention is to eliminate the above-mentioned conventional drawbacks and to
It is an object of the present invention to provide a robot control device for this type of robot, which has the ability to quickly and flexibly respond to changes in specifications, such as changes in the input conditions of external specific signals related to the operation control of the robot, on site.

Another object of the present invention is to control the operation of a robot using step information that sequentially advances each step of the operation, such as positioning, tightening screws, and energizing other end effectors.
In parallel with this, it is an object of the present invention to provide a robot control device having a function of simultaneously controlling peripheral devices such as a screw feeder and a conveyor station.

[Summary of the invention]

The present invention provides an end effector for raising and lowering a screw head, operating a screw driver, etc., using input/output of external specific signals related to robot operation control and step information that sequentially advances each stage of operation related to robot operation control. The output of energized and unenergized signals, and the input of signals from internal sensors such as limit switches and screw floating sensors are not directly input/output through the input/output interface that actually inputs and outputs signals, and these signals are Input/output is indirect input/output performed by reading and writing internal contacts addressed in the RAM, while the information of the internal contacts is constantly subjected to logical operations by scanning processing according to a ladder sequence based on sequence control information. Controlling the operation of the robot by inputting and outputting from the input/output interface that actually performs input and output;
The sequential processing of step information and the scanning processing of sequence information are simultaneously executed in parallel.

[Embodiments of the invention]

Specific embodiments of the present invention will be described in detail with reference to the drawings.

Figures 1 and 2 show a screw tightening robot (hereinafter referred to as robot) as a preferred example of the controlled object of the control device of the present invention. A screwdriver provided on a head 5 fixed to the tip of the second arm 4 by the pivoting action of the first arm 3 and the second arm 4 attached horizontally to the tip of the first arm 3 so as to be pivotable. 6 (hereinafter referred to as a driver) is guided to a predetermined screw hole position of the workpiece 80 to tighten the screw. The first arm 3 is driven and rotated by a servo motor provided on the rotation axis of the first arm 3 via a reduction gear 8, and the current position of the first arm 3 is determined by an encoder 9 directly connected to the output shaft of the servo motor. detected by. Like the first arm 3, the second arm 4 is driven and rotated by a servo motor 10 provided on the rotation axis of the second arm 4 via a reduction gear device 11.
The current position of is detected by an encoder 12 directly connected to the output shaft of the servo motor 10. The driver 6 includes a slide unit 13 that can slide vertically relative to the head 5.
The vertical movement of the slide unit 13 is performed by the piston movement of an air cylinder 14 fixed to the head 5.

When the driver 6 is guided directly above the screw hole position of the workpiece 80 by the rotational movement of the arm 3.4, the driver 6 is energized and the drive bit (hereinafter referred to as bit) 1
At the same time as 5 rotates, air valve 1 is connected to air cylinder 14.
6 is opened, compressed air is introduced in the downward direction, the slide unit 13 descends toward the workpiece 80, the driver 6 also descends toward the workpiece 80, and the bit 1 of the driver 6
5 is a Y pipe 17 provided in the path of the bit 15 on the way down, and after the previous screw tightening operation is completed, a screw that has been pressure-fed in advance through an air pipe 53 and maintained in the Y pipe 17 is obtained, and the screw is screwed into a workpiece 80. Screw it. When the head of the screw is screwed into the seating surface of the workpiece 80, the driving torque of the bit 15 reaches a predetermined torque, the torque limiter 18 is activated, and a torque limit signal is input to the control device. As a result, the driver 6 stops, and compressed air is introduced into the air cylinder 14 in the upward direction by opening the air valve 16, and the slide unit 13 retreats from the workpiece 80 and reaches the rising end, completing one screw tightening operation. do. In parallel with the upward movement of the slide unit 13, one screw is loaded by pressure into the Y pipe 17 through the air pipe 53 in preparation for the next screw tightening operation.

FIG. 3 is a block diagram of the robot control device 19 that controls the robot 1 and its peripheral devices. A path line 21 consisting of an address bus, a data bus, a control signal line, etc. is output from the CPU 20, and a ROM 22
The processing procedure of the CPU 20 is written in. RAM2
3 serves as a work register memory for the CPU 20.

The external specific input/output 24 is an input/output interface (hereinafter referred to as an input/output interface) that inputs specific signals related to operation control of the robot 1 such as return to origin, startup, and work start, and outputs specific signals such as positioning completion, screw tightening completion, work completion, etc. I/F the interface
The peripheral device control input/output 25 is an input/output I/F that controls peripheral devices such as a conveyor station separately from the operation of the robot 1, and the end effector control input/output 26 is an input/output I/F that controls peripheral devices such as a conveyor station separately from the operation of the robot 1. Outputs the air valve 16 on the slide unit 13, the energization/deenergization signal of the driver 6, etc.
It is an input/output I/F that inputs the torque limit signal of the torque limiter 18, the output signal of the upper end sensor of the slide unit 13, etc., and the internal sensor input 27 is the mechanical origin of the first and second arm servo control devices 28 and 29. signal.

This is an input I/F for inputting signals from the internal sensor of the robot 1, such as full limit detection signals, and these input/output I/Fs
The whole is indicated by 30.

For example, the storage device 31, which is an electrically programmable and erasable read-only storage device (EEPROM), stores information such as positions, screw tightening, and other conditional branches for sequentially advancing each step of the operation related to the operation control of the robot 1. Input Output,
Step information 32 such as waiting for input is stored,
At each stage of operation, the CPU 20 does not directly access the input/output I/F 30, but accesses the RAM 33.
The input/output I/F 3 is indirectly connected to the internal contact 34 addressed inside the input/output I/F 3 through read and write operations.
Inputs and outputs 0 on/off information. In the memory table 35 consisting of EEPROM etc., the internal contact 34 and the input/output I/F 3 are connected.
Sequence information 36 defining a so-called ladder sequence for connecting 0 is stored, and the CPU 20 runs the machine code written in the storage device 35, performs logical operations through constant scanning processing, and connects the internal contacts 34 and The input/output I/F 30 transmits and exchanges mutual on/off information using sequence information 36. In addition to connecting the internal contact 34 and the input/output I/F 30, the sequence information 36 also stores sequence information for connecting the input section 25a and the output section 25b of the peripheral device control input/output 25, and the robot 1 In parallel with the operation of the robot 1, peripheral devices are also controlled separately from the operation of the robot 1, and external specific input/output 24,
End effector control input/output 26, internal sensor input 2
7. It is possible to refer to the on/off information of the internal contact 34, and it is also possible to control peripheral devices in relation to the operating state of the robot 1.

In order to simultaneously execute the above operation control of the robot 1, the sequential progress of the processing of the step information 32, and the scanning processing of the sequence information 36 by the time-sharing processing operation of the CPU 20, an interrupt signal generator 37, for example, An interrupt signal 38 with a period of 2m5ec is input to the interrupt input terminal of the CPU 20, and when the CPU 20 receives the interrupt signal 38, it interrupts the sequential progress of step information processing that is currently being executed, and stores the condition code register at that time. The contents of the flag, program counter, stack pointer, etc. are stored and saved in the RAM 23, while the scanning process of the sequence information 36 is interrupted by the input of the previous interrupt signal 38, and the condition code register, flag, and program that were saved and stored at that time are saved. . The contents of the gram counter, stack pointer, etc. are restored from the RAM 23, and thereafter, the scanning process of the sequence information 36 is executed until the interrupt signal 38 is input again.
Every time 8 is input, the sequential progress processing of the step information 32 and the scanning processing of the sequence information 36 are performed alternately and continuously.

The interrupt signal generator 39 generates an interrupt signal 40 with a period of, for example, 20 msec, which is necessary for the regular control processing of the processing of the step information 32 and the processing of the sequence information 36, and gives priority to the signal 40 over the interrupt signal 38. High degree of CP
It is input to the interrupt input terminal of U20. Each keyboard display (hereinafter referred to as KD) 41 has a storage device 31.
．． 35, step information 32. This is for teaching and programming the sequence information 36, and when the robot control device 19 is in the teaching mode, by operating the KD 41, the step information 32. Sequence information 3
6 can be changed. Also, when the robot control device 19 is in automatic mode, the RA
The on/off states of the internal contacts 34 and input/output interface 30 of the M33 can be monitored by specifying the address of the signal line.

The first and second arm servo control devices 28 and 29 are connected to the path line 2 of the CPU 20 via bidirectional I/Fs 42 and 43, respectively.
1, and when position command information is output from the path line 21 to the bidirectional I/Fs 42 and 43, the first and second
The arm servo control devices 28 and 29 are controlled to position at the commanded position. The mechanical origin signals, zero, and full limit signals of the first and second arms 3.4 of the internal sensor force 27 are transferred from the internal sensor input 27 to the internal contact 34 by the scanning process of the CPU 20 according to the sequence information 36. If the information is referred to based on the servo internal sensor signal input line 44, accurate positioning to the machine origin cannot be performed due to a slight time lag caused by scanning, for example during origin return control. It is input to servo controllers 28 and 29. 1st, 2nd
When the positioning of the arm servo control devices 28 and 29 is completed, the path line 2
1 contains a status code as positioning processing completion information.

The current position information is output and the CPU 20 is notified of completion.

FIG. 4 shows a block diagram of the servo control device, and the same parts as in FIG. 3 are given the same reference numerals.

Both the first and second arm servo control devices 28 and 29 have the same configuration, and the first arm servo control device 28 will be explained as a representative. The two-phase pulse signal of the encoder 9 is sent to the counter 4.
5, the CPU 46 obtains current position information from the counter 45 according to a predetermined processing procedure stored in the ROM 47, calculates the current speed from this current position information, and receives position command information from the bidirectional I/F 42. Do a successive comparison with
The optimum duty command value and excitation signal for pulse width control of the servo motor 7 are calculated each time, and the PWM converter 48
．． It is output to the excitation direction control circuit 49. The motor driver 50 constituted by an H-type bridge transistor circuit is
The servo motor 7 is driven and controlled according to the output signals of the PWM converter 48 and the excitation direction control circuit 49 to perform positioning. C
RAM 51 which is the work register memory of PtJ46, the bidirectional I/F 42.43, counter 45, ROM
47, PWM converter 48, excitation direction control circuit 49, C
It is connected to a path line 52 consisting of an address bus, a data bus, a control signal line, etc. of the PU 46.

FIG. 5 is a circuit diagram showing a specific example of a part of the input/output I/F 30 and internal contacts 34, and the same parts as in FIG. 3 are given the same reference numerals. The CPU 20 connects to the RAM 33 via a pass line 21, a data selector 60, and an addressable latch 61 that constitute input and output I/Fs, respectively.
The D7 bit of the contents of each byte of the RAM 33 indicates the on/off state of the internal contact 34, and the data selector 60 and addressable latch 61 control the input/output I/O.
It constitutes F30. Note that if the input/output I/F 30 has a large number of input/output signal lines, the I/F may be configured by adding a data selector 60 and an addressable latch 61.

The RAM 33 and the CPU 20 are connected to an address bus 62 for accessing each contact of the internal contacts 34, a part D7 line 63 of a data line for reading and writing on/off information of the internal contacts 34, a read signal 64, and a write signal 6.
5 is connected, and the internal contacts 34 are assigned numbers from 300 to 399 as address numbers of the address line, for example.

Since the RAM 33 responds with address instruction signals numbered 300 to 399 among the signals on the pass line 21, the chip select signal 66 converts the signal on the address bus 62 to the decoder 67.
is decoded and output. Similarly, data selector 6
For example, 0 is the address number of the address line and is 100.
The lower three lines of the address bus 62, the read signal 64, the D7 data line 63, and the chip select signal 68 are connected to read the on/off state of the input, and the addressable latch 6
1 is the address number of the address line, from 200 to 20
It is assigned to No. 7, and is used to output on/off control commands and to read the on/off contents currently being output by the lower three lines of the address bus 62 and the read signal 64. A write signal 65 and a chip select signal 69 are connected. The on/off information is transmitted to each 11 of the D7 data line 63.
This corresponds to the HI+ level and the 'L'' level.

FIG. 6 is a flowchart showing the processing procedure for the operation control of the robot control device 19 and the operation control based on the step information 32. This processing procedure is written in the ROM 22, and when the robot control device 19 is powered on, the CPU 20 starts processing according to the machine code in the ROM 22, and first initializes the contents of the stack pointer, flags, etc. in the RAM 23. Then, it gives a RUN command for the sequence operation described later, and waits for the ON input of the origin return command at address 300 of the internal contact 34. Since the number 300 of the internal contact 34 is connected to the signal line 100 of the origin return command of the external specific input/output 24 according to the sequence information 36 (see Figure 7), when the ON command is input to the number 100, the number 300 turns on. Turns on and bidirectional I/F42.4
1 through 3. 2nd arm servo control device 28.29
A return-to-origin command is output to , the first and second arm servo control devices @28.29 start return-to-origin operations, and internal sensor signal input lines 44 for servo are sent from internal sensor inputs 27 Nos. 130 and 131. via the respective first arms 3. The mechanical origin signal of the second arm 4 is input, the second arm 4 waits at the mechanical origin, and completes the origin return operation. Next, wait for the ON input of the activation command of the internal contact 34, and in the same way as above, since the internal contact No. 301 is connected to the signal line No. 101 of the activation command of the external specific input/output 24 according to the sequence information 36, When No. 101 receives an on command, No. 301 turns on, and robot 1
enters the activated state and waits for a work start command from internal contact 34 No. 302. Now, on the conveyor, when the platen 82 carrying the work 80 arrives at the station of the robot 1 and is ready for screw tightening work, the work start signal No. 102 of the external specific input/output 24 is turned on by the signal output from the conveyor. The sequence information 36 turns on the work start signal line 302 of the internal contact 34, and the screw tightening work is started.
Referring to FIG. 8, the starting address of the CPU 20 is 80.
Step information 3 of storage device 31 allocated to address 00
The content of the OOO step 2 is read out, the execution content is displayed on the KD 41, and the content is decoded by the software interpreter and determined to be a position command. - For example, the step information 32 has a variable word length structure, the first byte means the type of instruction, "AO" is the position, and "A
3” indicates screw tightening, and if necessary, the data necessary to execute the command follows from the second byte, and the interpreter decodes the type of command and the number of bytes making up the command using the code of the first byte. It is now being determined.

The 000 step is a position command consisting of a word length of 7 bytes in this case, and its content is to move the first and second arms 3.4 to the first screw tightening positions of 123.45 and 321.09, respectively. , the operations shown in the processing flowchart of FIG. 9 are performed, positioning commands are issued from the bidirectional 1/F 42.43 to the first and second arm servo control devices 28, 29, respectively, and the arms move to the commanded positions. When the positioning operation is completed, the first and second arm servo control devices 28 and 29 output positioning completion responses including current position information to the two-way machine/F42 and 43, respectively, and the CPU 20
If the error between the current position of the second arm 3.4 and the commanded position is within the allowable range, it is determined that the positioning is complete, and a positioning completion time limit pulse signal is output to No. 351 of the internal contact 34 to complete the execution of the positioning command. The internal contact 351 is connected to No. 201 of the external specific input/output 24, and is output as a positioning completion signal to peripheral equipment. The execution step is incremented, the contents of step 001 are read out, the interpreter decodes and determines that it is a screw tightening command, and executes the screw tightening operation shown in the processing flowchart of FIG. Nos. 360 and 361 of the internal contacts 34 are respectively used to output a rotational drive signal for the driver 6 at No. 220 of the output I/F of the end effector control input/output 26, and to output an energization/deactivation signal for the lowering air valve 16 of the slide unit 13. It is connected by the sequence information 36, and the torque limit detection input signal No. 120 of the input I/F of the end effector control input/output 26 is connected to No. 362 of the internal contact 34, and the input I/F
Input 121 of the rise limit sensor of the air cylinder 14 of
No. is connected to No. 363 of internal contact 34.

When the number 360 of the internal contact 34 is turned on, the driver 6 is driven, and the number 361 of the internal contact 34 is turned on, and the air valve 16 is turned on.
When the screw is opened, the slide unit 13 is lowered relative to the workpiece 80 and the screw tightening operation is started. When the screw is tightened to the workpiece 80, the torque limit detection input signal 120
No. 360 turns on, and the CPU 20 turns off internal contact 34 No. 360 to stop driving the driver 6. Next, when the internal contact No. 361 corresponding to the air valve 16 is turned off, the slide unit 13 rises, and when the input No. 121 of the rise limit sensor is turned on, the internal contact No. 363 is turned on, and finally, the screw tightening completion time limit pulse signal is turned on internally. Contact point 35
It is output to number 2, and the series of screw tightening operations is completed. Furthermore, the execution step is incremented, and the 002 step is again a position command, and the 1st . In step 6003, in which the second arms 3.4 are moved to the next screw tightening position of 234.56.456.78, the screw tightening operation is carried out in the same manner as described above according to the screw tightening command. position command,
It is clear that in addition to screw tightening commands, input commands, output commands, conditional branch commands, etc. can also be used as necessary, but especially in input commands and output commands, the wire number of the input/output tip is input/output. It is also possible to directly access the peripheral device control input/output 25 as the code of the I/F 30 and control the devices connected to these, and the wire number of the input/output tip is assigned in the internal contact 34. It can also be connected to the input/output I/F 30 using the sequence information 36. The 004 step of the step information 32 stores the code "EE" indicating the end of the program, and the interpreter decodes and determines that this is the end of the step of this job, and the work completion time pulse is set at 3 of the internal contact 34.
50, and this content is given to 2 of external specific input/output 24.
It is actually output from number 00 to notify the station that the work has been completed. After this, robot 1 will move to the top OO of this job.
The position command of the O step is executed, and the screw tightening position is preliminarily moved directly above the screw tightening position to be executed by the screw tightening command of the next 001 step to shorten the takt time, and it waits for the next ON input of the work start signal No. 302.

When the next work start signal is input from No. 102 of the external specific input/output 24, the same operation as above is executed.

In parallel with the operation control of the robot 1 described above and the sequential progress of the processing of the step information 32, the scanning processing of the sequence information 36 is executed according to the flowchart shown in FIG. 11, and the sequence operation RUN immediately after power-on shown in FIG.
In response to the command, execution of the scanning process of the sequence information 36 is started.

FIG. 12 shows an example of the sequence information 36 written in the storage device 35. The contents of the ladder diagram shown in FIG. 7 are expressed and stored in the form of machine language of, for example, a z80 microcomputer, and the CPU 20 directly executes the program on the storage device 35 whose first address is assigned to address AOOO. That is, step 000.001 of the sequence information 36 is a step for transmitting the contents of the return-to-origin command input number 100 of the external specific input/output 24 to the number 300 of the internal contact 34. Assign the value 100 and then add 100 to the HL register to the A register.
Load the contents of number. At this time, if the origin return command is on, the D7 data line 63 becomes 1, so 1 byte of data "80" is loaded into the A register. At step 001, the CPU 20 assigns the value 300 to the HL register and then stores the contents of the A register in number 300, but since the contents of the A register is 108077, it is stored in the RAM.
Data "80" is written to No. 300 of the internal contact 34 of the RAM 33, and the ON command of the return-to-origin input No. 100 of the external specific input/output 24 is transmitted to No. 300 of the internal contact 34 of the RAM 33.

Thereafter, logical operations on 5TRIOI, 0UT301, and sequence information 36 are performed in the same manner. When the last command of the sequence information 36 written in the storage device 35 is executed, the next command is written to jump to address AOOO, and the CPU 20 executes the process again from address A000, and the scanning process is performed according to the sequence information 36. be exposed.

During execution of step information 32, interrupt signal 38 is CP
When input to the interrupt terminal of U20, the condition code register, stack pointer, program counter, etc. of the CPU 20 at this point are stored in the RAM 23 by the interrupt processing program as shown in the flowchart of FIG. 13 and the time chart of FIG. On the other hand, during the execution of the previous sequence information 36, the execution of the process was interrupted due to the input of the interrupt signal 38, and the above contents were saved.
After returning from AM23, execution of the processing of the sequence information 36 is restarted, and in this way, each time the interrupt signal 38 is input, the processing of the step information 32 and the processing of the sequence information 36 are resumed.
The processing of the step information 32 and the sequence information 36 are executed in parallel in parallel by the time-sharing processing operation of the CPU 20.

As shown in the flowchart of FIG. 15, timer processing such as outputting a work completion time limit pulse is executed periodically by non-maskable interrupt processing, and for example, the contents of the timer value set in the RAM 23 are transmitted every time an interrupt processing occurs. Timer processing is performed by decrementing the value.

In the above operation, the screw tightening work is not started simply by inputting a work start signal as a condition for starting work, which is the object of the present invention, but in order to improve the reliability of the screw tightening work, A sensor detects the acceptability of the rainbow posture of the work 80 flowing in, and the signal line 110 of the input section 25a of the peripheral device control input/output 25 receives the sensor output signal indicating that the placement posture is OK, and the signal line 110 of the input section 25a of the work start command. When starting the screw tightening work by taking the logical product of the signal line No. 102 of the external specific input/output 24, if a part of the storage device 35 is changed using the K D41, the content of the changed part of the ladder diagram will be changed to the 16th ladder diagram. As shown in the figure, signal line 102 and signal line 11
It can be easily changed so that when the above is logically ANDed and both of the above are turned on, internal contact No. 302 is turned on and a command to start work is issued. In this case, the command for robot 1 to start work is Since the determination is made using the internal contact point 302, there is no need to change the flowchart in FIG. 6, and therefore the contents of the ROM 22 may remain as they were before.

If it becomes necessary to output the screw tightening completion signal from internal contact No. 352 at No. 201 of the external specific input/output 24 instead of outputting the positioning completion signal from internal contact No. 351, please refer to Fig. 17. As shown in the ladder diagram, the output light from internal contact No. 352 is reconnected to No. 201 of external specific input/output 24.

In order to control peripheral devices by the peripheral device control device input/output 25, as shown in FIG.
By performing a logical AND with No. 13 and writing this result into the sequence information 36 so as to output it from No. 211, it is possible to control the peripheral equipment separately and in parallel with the operation of the robot 1. In equipment control, each stage of the operation of the screw tightening robot 1 such as completion of positioning and completion of screw tightening, or the operation of the robot 1 at the input/output 26 for end effector control such as a machine origin signal and a rise limit signal, and the internal sensor input 27 By using signals indicating the status, the robot 1 and peripheral devices can be operated in association with each other.In the above explanations, the sequence information 36 has been explained about AND and OR, but as a type of instruction, it can be operated by a general programmer. It is clear that instructions using subroutine processing such as timer, counter, and rising differential, which are also used in the controller, can also be used.

FIG. 19 is a block diagram of a robot control device 19 showing another embodiment of the present invention, in which the CPU 70 is used instead of the time-sharing processing operation of the CPU 20 to perform specialized scanning processing of the sequence information 35 to improve processing speed. The same parts as in the block diagram of FIG. 3 are given the same reference numerals. The contents of the internal contact 34 are C
The processing operation of the PU 70 causes input/output to the input/output I/F 30 according to the contents of the sequence information 36. RAM33
In order to prevent the CPUs 20.70 from being accessed at the same time, a signal line 74 is provided to communicate the operating states of the CPUs 20.70 to each other. Furthermore, ROM72
, RAM73, and KD71 are ROM22 and RAM23, respectively.
, KD41 is provided for the same purpose.

〔Effect of the invention〕

According to the invention. Actual signals such as input/output of external specific signals related to robot operation control, output of end effector energization/deenergization signals based on step information that sequentially advances each step of operation related to robot operation control, input of limit switch signals, etc. These signals are not directly input/output through the input/output I/F that performs input/output, but are indirectly input/output by reading and writing to internal contacts addressed in the RAM. Information is input/output from the input/output I/F where logical operations are constantly performed by scanning processing according to the ladder sequence based on sequence control information, and the input/output is actually performed, and the above-mentioned robot operation control and step information processing progress sequentially. Since the scanning process of sequence information is executed in parallel, it is possible to quickly and flexibly respond on-site to changes in usage, such as changes in the input conditions of external specific signals related to robot operation control, and also to In addition to the robot operation control based on step information that sequentially progresses through each stage of operations such as screw tightening and other operations such as energization and de-energization of end effectors, there is an effect that peripheral devices can be simultaneously controlled in parallel.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a front view of the robot, and FIG. 2 is a plan view of FIG. 1. Fig. 3 is a block diagram of the robot control device, Fig. 4 is a block diagram of the servo control device, Fig. 5 is a circuit diagram showing a specific example of the input/output I/F and internal contacts, and Fig. 6 is a block diagram of the robot control device. Flowchart showing the processing procedure for operation control of the robot control device and operation control based on step information, No. 7
The figure is a ladder diagram of sequence information, Figure 8 is a diagram showing the contents of step information, Figure 9 is a flowchart showing the processing procedure for position commands, and Figure 10 is the processing procedure for screw tightening commands. Flowchart, FIG. 11 is a flowchart showing the processing procedure of sequence information, FIG. 12 is a diagram showing the contents of sequence information, FIG. 13 is a flowchart showing the processing procedure of interrupt processing, and FIG. 14 is a time-sharing processing operation. FIG. 15 is a flowchart showing the processing procedure of interrupt processing, FIGS. 16 to 18 are ladder diagrams, and FIG. 19 is a block diagram of a robot control device showing another embodiment of the present invention. . In the figure, 20 is a microcomputer, 30 is an input/output I/F, 3
1 and 35 are storage devices, 32 is step information, and 33 is RA
M, 34 is an internal contact, and 36 is sequence information. Name of Patent Applicant Hitachi Koki Co., Ltd. No. 20 1) Mouth Figure 7 Figure 12 Moya 130 Mustard! 60! 4170 1st s port

Claims (1)

[Claims] 1. Input/output of external specific signals for controlling operation, energizing the end effector to sequentially advance each stage of operation based on step information programmed in advance and stored in a storage device. A robot control device that inputs and outputs signals to and from control equipment via an input/output interface, such as outputting signals and inputting signals from internal sensors, and performs control processing using a microcomputer. A random access memory is provided in the output circuit, and signal input/output operations are performed by read/write operations of internal contacts addressed in the random access memory that are not directly connected to the control equipment, and the internal contacts are directly connected to the control equipment. Between the input and output interfaces, mutual signals are transmitted through logic operations of signal on/off based on sequence control information programmed in advance and stored in a storage device, and operation control and step information processing are executed sequentially. A robot control device characterized in that a robot control device is configured to simultaneously execute scanning processing of sequence information and scanning processing of sequence information in parallel. 2. The apparatus according to claim 1, wherein the sequential execution of the operation control and step information processing and the execution of the sequence information scanning process are simultaneously performed in parallel by time-sharing processing operations of a microcomputer. Robot control device.