JP6613849B2 - Robot controller - Google Patents

Description

  The present invention constitutes a robot system comprising a robot having a plurality of rotating units and a motor that drives a rotating shaft of each rotating unit, and a rotation detecting unit that detects rotational position information of the rotating shaft, The present invention relates to a robot control device that controls driving.

  As this type of robot control device, for example, as shown in Patent Document 1 below, one having a monitoring unit that monitors the presence or absence of an abnormality of a robot based on rotational position information from a rotation detection unit is known. When the monitoring unit detects an abnormality of the robot, the monitoring unit cuts off the power supply from the external power source to the robot. As a result, the robot is stopped and the safety of the robot system is enhanced.

  By the way, in order to prevent an operator from entering the operation area of the robot in the production line, a safety measure has been conventionally taken in which the operation area is surrounded by a safety protection fence. In recent years, it has been considered that a robot and an operator work together in a production line in order to improve the efficiency of product production. In this case, for example, a safeguard fence may not be installed, so it is necessary to take measures that can guarantee the safety of the robot system.

  Therefore, as a countermeasure, it has been proposed to employ a robot control device having a redundant configuration. Specifically, this control device includes a first monitoring unit and a second monitoring unit. Each monitoring unit monitors the presence / absence of an abnormality of the robot based on the input rotational position information. When it is determined that there is an abnormality, the power supply to the robot is interrupted.

  The first monitoring unit sequentially performs each of the plurality of processes based on the rotational position information in a predetermined order for each calculation cycle. The second monitoring unit sequentially performs each of the same processes as the plurality of processes performed by the first monitoring unit in the same order as the predetermined order performed by the first monitoring unit for each calculation cycle. The first monitoring unit determines that an abnormality has occurred in the robot system when it determines that the processing result performed by itself and the processing result acquired from the second monitoring unit are different from each other. The second monitoring unit determines that an abnormality has occurred in the robot system when it determines that the processing result performed by itself and the processing result acquired from the first monitoring unit are different from each other. The redundant system configuration described above ensures the safety of the robot system.

Japanese Patent No. 5271499

  Here, when an abnormality occurs in either of the first and second monitoring units, the processing result obtained as a result of the normal processing based on the rotational position information being performed in the monitoring unit in which no abnormality has occurred, and the abnormality An abnormality may occur in which the normal monitoring process is not performed in the generated monitoring unit and the processing result obtained is the same. It is difficult to detect such an abnormality with the redundant configuration described above.

  The present invention has been made to solve the above-described problem, and was obtained as a result of normal processing based on rotational position information and obtained when normal processing was not performed. The main object is to provide a robot control device that can detect an abnormality even when an abnormality occurs that has the same processing result.

  According to a first aspect of the present invention, there is provided a robot system including a robot having a plurality of rotating units and a motor that drives a rotating shaft of each rotating unit, and a rotation detecting unit that detects rotation position information of the rotating shaft, In the robot control device for driving and controlling the robot, the rotational position information is configured to be input, and a first monitoring unit and a second monitoring unit that monitor presence or absence of abnormality of the robot based on the input rotational position information. The first monitoring unit sequentially performs each of a plurality of processes based on the input rotational position information in a predetermined order every calculation cycle, and the second monitoring unit performs every calculation cycle In addition, each of the same processes as the plurality of processes performed by the first monitoring unit is sequentially performed in the same order as a predetermined order performed by the first monitoring unit, and the first monitoring unit performs the input of the rotation Place In the processing based on information, when it is determined that the processing result performed by itself and the processing result acquired from the second monitoring unit are different from each other, it is determined that an abnormality has occurred in the robot system, and the second monitoring unit In the processing based on the input rotational position information, if it is determined that the processing result performed by itself and the processing result acquired from the first monitoring unit are different from each other, the robot system is abnormal. judge.

  In the first aspect of the invention, the first monitoring unit outputs a pulse signal after completion of at least one of the plurality of processes, and the second monitoring unit outputs at least one of the plurality of processes. A pulse signal is output after completion of the specific processing, and the pulse signal output from the first monitoring unit is configured to be input, and the time interval at which the pulse signal is input matches a predetermined first threshold time. When it is determined that the first monitoring unit does not perform an abnormality, the first diagnosis unit that determines that an abnormality has occurred and the pulse signal output from the second monitoring unit can be input, and the pulse signal is input. And a second diagnosis unit that determines that an abnormality has occurred in the second monitoring unit when it is determined that the time interval to be performed does not coincide with a predetermined second threshold time.

  A processing result obtained as a result of the normal processing based on the rotation position information caused by an abnormality in either the first or second monitoring unit, and a processing result obtained when the normal processing is not performed May be the same. Specifically, for example, as a result of normal processing based on rotational position information, this abnormality does not yield the same processing result as the previous time, but has the same processing result as the previous time even if no processing has been performed. Abnormal fixation.

  Even when the processing results are the same in the first and second monitoring units, the state in which an abnormality has occurred in either the first or second monitoring unit is originally the first or second monitoring unit. It is necessary to detect that an abnormality has occurred in any of the above. However, it is difficult to detect such an abnormality with the redundant configuration described in the background art. In particular, in a situation where the stop state of the robot is maintained, there are many cases where the processing result based on the rotational position information is the same between the previous time and the current time, and it is more difficult to detect the sticking abnormality.

  Therefore, in the above invention, each of the first monitoring unit and the second monitoring unit outputs a pulse signal after completion of at least one specific process among the plurality of processes. Even when the processing results are the same in the first and second monitoring units, in the state where an abnormality has occurred in either the first or second monitoring unit, the processing time in the monitoring unit in which the abnormality has occurred There is a phenomenon in which the processing time deviates from the reference time, for example, becomes longer or faster than the reference time (for example, the time assumed at the time of design). In this case, the time interval of the pulse signal output from the first monitoring unit is deviated from the reference time interval.

  In view of this point, the invention includes a first diagnosis unit and a second diagnosis unit. The first diagnosis unit is configured to be able to input a pulse signal output from the first monitoring unit. The first diagnosis unit determines that an abnormality has occurred in the first monitoring unit when it is determined that the time interval at which the pulse signal is input does not coincide with a predetermined first threshold time. The second diagnosis unit is configured to be able to input the pulse signal output from the second monitoring unit. The second diagnosis unit determines that an abnormality has occurred in the second monitoring unit when determining that the time interval at which the pulse signal is input does not coincide with the predetermined second threshold time.

  According to the above-described invention described above, the processing result of each monitoring unit is obtained as a result of normal processing based on rotational position information, or is obtained when normal processing is not performed. Can be identified. Therefore, this is a case where an abnormality occurs in which the processing result obtained as a result of the normal processing based on the rotational position information is the same as the processing result obtained when the normal processing is not performed. However, the abnormality can be detected.

  Note that which of the plurality of processes performed by each monitoring unit, after which the pulse signal is output, may be matched between the first monitoring unit and the second monitoring unit, or may be different. The first and second threshold times used by the first and second diagnostic units are set to the same value or different values depending on which of the plurality of processes is completed after the pulse signal is output. Or set to

  According to a second aspect of the invention, the first monitoring unit outputs a pulse signal before completion of all of the plurality of processes and after completion of at least one specific process among the plurality of processes, and the second monitoring unit A pulse signal is output before completion of all of the plurality of processes and after completion of at least one specific process among the plurality of processes.

  According to the above invention, since the pulse signals can be output from the first and second monitoring units in the middle of completing the plurality of processes, an abnormality in which the processing time deviates from the reference time is detected during the plurality of processes. It can be done easily. Furthermore, in the above invention, since the pulse signals can be output from the first and second monitoring units before completion of all of the plurality of processes, it is possible to quickly detect an abnormality in which the processing time deviates from the reference time.

  Incidentally, as the first diagnosis unit, specifically, for example, as in the third invention, when it is determined that the time interval at which the pulse signal is input does not coincide with the first threshold time, the first monitoring unit It is possible to adopt a configuration for determining that an abnormality in the processing time has occurred. Further, as the second diagnosis unit, specifically, for example, as in the second invention, when it is determined that the time interval at which the pulse signal is input does not coincide with the second threshold time, the second monitoring unit It is possible to adopt a configuration for determining that an abnormality in the processing time has occurred.

  According to a fourth aspect of the invention, each of the first monitoring unit and the second monitoring unit outputs a pulse signal after completion of each of a plurality of specific processes among the plurality of processes, and an abnormality is detected in the first monitoring unit. If not, time intervals of the pulse signals that are temporally adjacent to each other among the pulse signals that are output after completion of each of the plurality of specific processes are different from each other and set to a predetermined time interval. In the case where no abnormality has occurred in the second monitoring unit, time intervals of temporally adjacent pulse signals among the pulse signals output after completion of each of the plurality of specific processes are different from each other and The time interval is set to a predetermined time interval, and the first diagnosis unit determines that the time interval sequence of the input pulse signal does not match the predetermined time interval sequence. In this case, it is determined that the order of the plurality of processes has changed in the first monitoring unit, and the second diagnosis unit determines a time in which the order of the time intervals of the input pulse signals is predetermined. When it is determined that the order of the intervals does not match, it is determined that the order of the plurality of processes is changed in the second monitoring unit.

  In either the first monitoring unit or the second monitoring unit, the order of the plurality of processes is switched, and a switching abnormality in which the order of the plurality of processes is different from the predetermined order may occur. When a processing result of a certain process among a plurality of processes is used for a process immediately after that, there is a concern that the first and second monitoring units may not be able to execute the processes monitored by each other when a switching abnormality occurs.

  Therefore, in the above invention, each of the first monitoring unit and the second monitoring unit outputs a pulse signal after completion of each of the plurality of specific processes among the plurality of processes. Then, when no abnormality has occurred in the first monitoring unit, time intervals between temporally adjacent pulse signals among pulse signals output after completion of each of the plurality of specific processes are different and predetermined. The time interval is set. In addition, when no abnormality has occurred in the second monitoring unit, time intervals of pulse signals adjacent in time among pulse signals output after completion of each of the plurality of specific processes are different and predetermined. The time interval is set.

  When the time interval of the pulse signal is set in this way, if a switching abnormality occurs, the order of the time intervals of the input pulse signals becomes different from the order of the predetermined time intervals. Therefore, in the above invention, when the first diagnosis unit determines that the order of the time intervals of the input pulse signal does not match the order of the predetermined time intervals, the order of a plurality of processes is changed in the first monitoring unit. Is determined to have occurred. On the other hand, when the second diagnosis unit determines that the time interval order of the input pulse signal does not match the predetermined time interval order, a plurality of processes are switched in the second monitoring unit. Is determined. As described above, according to the above-described invention, it is possible to detect the change abnormality.

  Note that the time intervals of the first pulse signals output after completion of each of the plurality of specific processes may be matched or different in each of the first monitoring unit and the second monitoring unit.

  According to a fifth aspect of the invention, each of the first monitoring unit and the second monitoring unit outputs a pulse signal after completion of each of a plurality of specific processes among the plurality of processes, and an abnormality is detected in the first monitoring unit. If not, the number of pulses of the pulse signal output after completion of each of the plurality of specific processes is set to a different number and a predetermined number of pulses, and the second monitoring unit In the case where no abnormality has occurred, the number of pulses of the pulse signal output after completion of each of the plurality of specific processes is different from each other and set to a predetermined number of pulses, When the first diagnosis unit determines that the order of the number of pulses of the input pulse signal does not match the order of the predetermined number of pulses, the first monitoring unit may When it is determined that a change in the order of logic has occurred, and the second diagnosis unit determines that the order of the number of pulses of the input pulse signal does not match a predetermined order of the number of pulses, The second monitoring unit determines that the order of the plurality of processes has changed.

  The switching abnormality described above may occur in either the first monitoring unit or the second monitoring unit. Therefore, in the above invention, each of the first monitoring unit and the second monitoring unit outputs a pulse signal after completion of each of the plurality of specific processes among the plurality of processes. When no abnormality has occurred in the first monitoring unit, the number of pulse signals output after completion of each of the plurality of specific processes is set to a predetermined number of pulses different from each other. Further, when there is no abnormality in the second monitoring unit, the number of pulse signals output after completion of each of the plurality of specific processes is set to a predetermined number of pulses that are different from each other.

  When the number of pulses of the pulse signal is set in this way, if a switching abnormality occurs, the order of the number of pulses of the input pulse signal becomes different from the order of the predetermined number of pulses. Therefore, in the above invention, when the first diagnosis unit determines that the order of the number of pulses of the input pulse signal does not match the order of the predetermined number of pulses, the order of a plurality of processes is changed in the first monitoring unit. Is determined to have occurred. On the other hand, if the second diagnosis unit determines that the order of the number of pulses of the input pulse signal does not match the order of the predetermined number of pulses, the order of a plurality of processes is changed in the second monitoring unit. It is determined that

  As described above, according to the above-described invention, it is possible to detect the change abnormality. Moreover, according to the above-described invention, even when the time intervals of the first pulse signals output after completion of each of the plurality of specific processes are set to be equal to each other, the change of the plurality of processes can be identified by the number of pulses. Therefore, it is possible to detect a change abnormality.

  Note that the number of pulses of the pulse signal output after completion of each of the plurality of specific processes may be the same or different in each of the first monitoring unit and the second monitoring unit.

  Here, the sixth invention can be adopted as a configuration having the same effect as the fifth invention. According to a fifth aspect of the invention, each of the first monitoring unit and the second monitoring unit outputs a pulse signal after completion of each of a plurality of specific processes among the plurality of processes, and an abnormality is detected in the first monitoring unit. If not, the pulse widths of the pulse signals output after completion of each of the plurality of specific processes are different from each other and set to a predetermined pulse width, and the second monitoring unit In the case where no abnormality has occurred, each pulse width of the pulse signal output after completion of each of the plurality of specific processes is different from each other and set to a predetermined pulse width. When the first diagnosis unit determines that the order of the pulse widths of the input pulse signals does not match a predetermined order of the pulse widths, the first monitoring unit may When it is determined that a change in the order of logic has occurred, and the second diagnosis unit determines that the order of the pulse widths of the input pulse signals does not match a predetermined order of the pulse widths, The second monitoring unit determines that the order of the plurality of processes has changed.

  Note that the pulse widths of the pulse signals output after completion of each of the plurality of specific processes may be matched or different between the first monitoring unit and the second monitoring unit.

  According to a seventh aspect of the present invention, there is provided a drive unit configured to be operable by being supplied with electric power from an external power source and driving the motor by receiving a control signal for driving control of the robot, and the drive unit from the external power source A power supply cutoff unit that switches a power supply state to the motor via a power supply permission state or a power supply cutoff state, and the first diagnosis unit has a time interval at which the pulse signal is input as the first time interval. When it is determined that it does not coincide with one threshold time, the power cut-off unit is switched so as to switch from the power supply permission state to the power cut-off state, and the second diagnosis unit has a time interval at which the pulse signal is input. When it is determined that it does not coincide with the second threshold time, the power supply cutoff unit is switched to switch from the power supply permission state to the power supply cutoff state.

  According to the above-described invention, when an abnormality in which the processing time deviates from the reference time is detected, the power supply cutoff unit can be switched to the cutoff state, and the robot can be prevented from operating. Therefore, according to the above invention, the safety of the robot system can be improved.

  The power supply interrupting unit is specifically a power source that switches the electrical connection state between the driving unit and the external power source to either the conducting state or the interrupting state, as in the eighth invention, for example. A configuration such as a blocking unit can be employed. In this case, switching the power supply cutoff unit to switch from the power supply permission state to the power supply cutoff state means that the power supply cutoff unit switches the connection state of the power supply cutoff unit from the conduction state to the cutoff state. This means that the part is switched.

  According to a ninth aspect of the invention, each of the first monitoring unit and the second monitoring unit sets the power supply cutoff unit from the power supply permission state to the power supply cutoff state when the robot is maintained in a stopped state. It is characterized in that the presence or absence of an abnormality in the robot system is monitored without switching operation.

  From the standpoint of improving the efficiency of product manufacture, it is conceivable to maintain the robot in a stopped state without interrupting the power supply from the external power supply to the motor. Here, when the robot is maintained in a stopped state, an abnormality occurs in either the first or second monitoring unit, and a processing result obtained as a result of normal processing based on the rotational position information An abnormality may occur in which the processing result obtained when the normal processing is not performed is the same. When the stop state of the robot becomes long, there is a concern that the safety of the robot system cannot be secured when an abnormality occurs in the other monitoring unit.

  Therefore, the invention includes a configuration for outputting a pulse signal from the first and second monitoring units, a first diagnostic unit, and a second diagnostic unit. Thereby, even when the robot is stopped, an abnormality occurs in either the first or second monitoring unit, and the processing result obtained as a result of the normal processing based on the rotational position information and the normal processing are performed. An abnormality that is the same as the processing result obtained without being performed can be detected, and when the abnormality is detected, the power supply from the external power source to the motor can be cut off.

The figure which shows the outline | summary of the robot system which concerns on 1st Embodiment. The figure which shows the structure of a safety controller. The figure which shows the output mode of the pulse signal of a 1st, 2nd monitoring part. The flowchart which shows the procedure of an abnormality detection process. The time chart for demonstrating the detection method of sticking abnormality. The figure which shows the output mode of the pulse signal of the 1st, 2nd monitoring part which concerns on 2nd Embodiment. The time chart for demonstrating the detection method of a switching abnormality. The time chart for demonstrating the detection method of the change abnormality which concerns on 3rd Embodiment. The figure which shows the structure of the safety controller which concerns on other embodiment.

<First Embodiment>
Hereinafter, a first embodiment embodying a robot control device will be described with reference to the drawings. The robot according to the present embodiment is used in an assembly system such as a machine assembly factory as an industrial robot, for example.

  First, the outline of the robot system according to the present embodiment will be described with reference to FIG.

  As shown in FIG. 1, the robot 10 constituting the robot system includes a plurality of rotating units and joints that connect the rotating units to each other. The robot 10 according to the present embodiment is configured as a 6-axis vertical articulated robot.

  The robot 10 includes a fixed portion 11 that is fixed to a floor or the like, and a first rotating portion 12 that is provided above the fixed portion 11. The arm of the robot 10 includes a lower arm 13, an upper arm 14, a wrist portion 15, and a hand portion 16 in addition to the first rotating portion 12. The 1st rotation part 12 is equivalent to the root part on the opposite side to the arm tip part among the both ends of an arm. The first rotating unit 12 is rotatable in the horizontal direction with a first axis J1 extending in the vertical direction as a rotation center.

  The first rotating portion 12 is connected to the lower end portion of the lower arm 13 as the second rotating portion so as to be rotatable clockwise or counterclockwise about a second axis J2 extending in the horizontal direction as a rotation center. . The upper arm 14 is coupled to the upper end of the lower arm 13 so as to be rotatable clockwise or counterclockwise about a third axis J3 extending in the horizontal direction. The upper arm 14 is configured to be divided into two arm portions on the base end side (the joint side having the third axis J3 as the rotation center during rotation) and the tip end side, and the base end side is the third rotation. The first upper arm 14A (third rotating part) as a part, and the tip side is a second upper arm 14B (fourth rotating part) as a fourth rotating part. The second upper arm 14B is rotatable in the torsional direction with respect to the first upper arm 14A, with a fourth axis J4 extending in the longitudinal direction of the upper arm 14 as a rotation center.

  A wrist portion 15 as a fifth rotating portion is provided at the distal end portion of the second upper arm 14B. The wrist portion 15 is rotatable with respect to the second upper arm 14B with a fifth axis J5 extending in the horizontal direction as a rotation center. A hand portion 16 as a sixth rotating portion for attaching a work, a tool, or the like is provided at the distal end portion of the wrist portion 15. The hand portion 16 is rotatable in the torsional direction with the sixth axis J6 that is the center line as the rotation center. A TCP (Tool Center Point), which is the center point of the hand unit 16, is set as the control point 16a.

  Each rotating part of the robot 10 is driven by a motor 41 (see FIG. 2) provided correspondingly. The motor 41 can rotate in both forward and reverse directions, and each rotating unit is driven by the drive of the motor 41 with reference to the origin position.

  The robot system further includes a controller 20 that controls the robot 10 and a teaching pendant 30 that is electrically connected to the controller 20. The teaching pendant 30 includes a microcomputer including a CPU, ROM, and RAM, various manual operation keys, a display, and the like. The pendant 30 can communicate with the controller 20. The operator can manually operate the pendant 30 to create, modify, register, and set various parameters for the operation program of the robot 10. In teaching for correcting the operation program, etc., the teaching point through which the control point 16a passes in the work is taught. The operator can operate the robot 10 through the controller 20 based on the teaching operation program.

  Next, the electrical configuration of the robot system will be described with reference to FIG.

  The controller 20 includes a drive unit 21 that drives a motor 41 using an external power supply 40 (commercial power supply) as a power supply source. In the present embodiment, the drive unit 21 includes a three-phase inverter that converts an input DC voltage into an AC voltage and applies it to the stator winding of the three-phase motor 41. The inverter includes three serially connected bodies of a high side switch and a low side switch. The motor 41 and the drive unit 21 are individually provided corresponding to each rotation unit of the robot 10.

  The controller 20 includes a drive power generation unit 22 that generates a DC voltage to be supplied to the drive unit 21 based on the AC voltage output from the external power supply 40. The drive power generation unit 22 includes a rectifier that converts an AC voltage output from the external power supply 40 into a DC voltage, and a chopper type boost converter that boosts the DC voltage output from the rectifier.

  The controller 20 includes a first power cutoff unit 23 and a second power cutoff unit 24 provided on an electrical path connecting the external power supply 40 and the drive power generation unit 22. In the present embodiment, a contactor (electromagnetic contactor) is used as each of the power cutoff units 23 and 24. Each of the power cutoff units 23 and 24 is electrically connected between the external power supply 40 and the drive power generation unit 22 when the connection state thereof is turned on, and the connection state is cut off. The external power supply 40 and the drive power generation unit 22 are electrically disconnected.

  The controller 20 includes a control unit 25 that performs drive control of the motor 41. The control unit 25 is configured mainly with a microprocessor, and is configured to be able to input an output signal of an encoder 42 as a rotation detection unit that detects rotation position information of the motor 41. The encoder 42 is provided individually corresponding to each motor 41. The control unit 25 generates a PWM signal that is a control signal based on the rotational position information in order to control the control amount (for example, the rotation speed) of each motor 41 to the command value, and outputs the PWM signal to the drive unit 21. Output.

  The controller 20 includes a first monitoring unit 26 and a second monitoring unit 27 that monitor whether the robot 10 is abnormal. Each of the monitoring units 26 and 27 is configured to be able to input the rotational position information output from the encoder 42. When the first monitoring unit 26 detects an abnormality of the robot 10, the first monitoring unit 26 switches the first power supply cutoff unit 23 from the conduction state to the cutoff state. When the abnormality of the robot 10 is detected, the second monitoring unit 27 switches the second power supply cutoff unit 24 from the conduction state to the cutoff state. When at least one of the first power cutoff unit 23 and the second power cutoff unit 24 is cut off, power supply from the external power supply 40 to the drive unit 21 is cut off, and the robot 10 is stopped.

  When each of the first monitoring unit 26 and the second monitoring unit 27 detects an abnormality of the robot 10, the first monitoring unit 26 and the second monitoring unit 27 notify the control unit 25 accordingly. When the abnormality of the robot 10 is notified, the control unit 25 stops outputting the PWM signal to the drive unit 21. Thereby, the drive control of the robot 10 is stopped.

  A safety input signal which is a binary logic signal is input to the first and second monitoring units 26 and 27. In the present embodiment, the safety input signal indicates that it is safe by a logic H, and indicates that it is not safe by a logic L. The first and second monitoring units 26 and 27 permit driving control of the robot 10 by the control unit 25 on condition that a logic H safety input signal is input. On the other hand, when the first monitoring unit 26 determines that a logic L safety signal is input, the first monitoring unit 23 switches the first power supply cutoff unit 23 to the cutoff state, and the second monitoring unit 27 receives a logic L safety signal. When it determines with having been carried out, the 2nd power supply interruption | blocking part 24 is switched to an interruption | blocking state.

  The case where the logic of the safety input signal becomes L is, for example, a case where an emergency stop switch is pushed by an operator or an operator enters a no-entry area partitioned by a light curtain.

  When each of the first monitoring unit 26 and the second monitoring unit 27 detects a mismatch between its own processing result and the processing result of the other party, an abnormality occurs in either the first monitoring unit 26 or the second monitoring unit 27. Judge that it is.

  Specifically, the first monitoring unit 26 sequentially performs each of a plurality of processes based on the rotational position information from the encoder 42 in a predetermined order every calculation cycle. In the present embodiment, as shown in FIG. 3, the first monitoring unit 26 acquires a safety input signal and rotation position information of the encoder 42 corresponding to each rotation axis, a position calculation process, These processes are sequentially performed in the order of the speed calculation process, the position monitoring determination process, and the speed monitoring determination process.

  The position calculation process is a process of calculating the current position of the control point 16a of the robot 10 by a forward conversion process using the rotational position information from the encoder 42 as an input. The speed calculation process is a process of calculating the operating speed of the control point 16a based on the current position of the control point 16a calculated by the position calculation process and the position of the control point 16a calculated one calculation cycle before. . The position monitoring determination process is a process for determining whether or not the current position of the control point 16a calculated by the position calculation process is within a predetermined operation region. The speed monitoring determination process is a process for determining whether or not the operation speed calculated by the speed calculation process is equal to or less than a specified speed.

  The second monitoring unit 27 sequentially performs each of a plurality of processes based on the rotational position information from the encoder 42 in a predetermined order every calculation cycle. In the present embodiment, as shown in FIG. 3, the second monitoring unit performs acquisition processing, position calculation processing, speed calculation processing, position monitoring determination processing, and speed for each calculation cycle in the same manner as the first monitoring unit. These processes are sequentially performed in synchronization with the first monitoring unit 26 in the order of the monitoring determination process. In the present embodiment, one calculation cycle of the first monitoring unit 26 and one calculation cycle of the second monitoring unit 27 are set to the same cycle.

  The first monitoring unit 26 and the second monitoring unit 27 are configured to be able to communicate with each other. When the first monitoring unit 26 determines that the processing result performed by the first monitoring unit 26 is different from the processing result acquired from the second monitoring unit 27 in each of the five processes illustrated in FIG. Is switched off. Specifically, for example, if the first monitoring unit 26 determines that the logic of the safety input signal acquired in the acquisition process and the logic of the safety input signal acquired from the second monitoring unit 27 do not match, 1. Switch the power supply cut-off unit 23 to the cut-off state.

  When the second monitoring unit 27 determines that the processing result performed by the second monitoring unit 27 is different from the processing result acquired from the first monitoring unit 26 in each of the five processes illustrated in FIG. Is switched off.

  In the present embodiment, the first and second monitoring units 26 and 27 do not switch the first and second power shut-off units 23 and 24 to the shut-off state when the robot 10 is maintained in the stopped state. 10 has a stop monitoring function for monitoring that 10 is maintained in the stop state. When the first and second monitoring units 26 and 27 monitor the robot 10 with the stop monitoring function and detect an abnormality in the robot system, the first and second power shut-off units 23 and 24 are turned off. Switch.

  Here, under the situation where the stop state of the robot 10 is monitored by the stop monitoring function, the process based on the rotational position information shown in FIG. 1 or the second monitoring unit 26 or 27 may occur. In this case, since the robot 10 is in a stopped state, the processing result obtained as a result of the normal processing based on the rotational position information of the encoder 42 and the normal processing are not performed. Results in the same processing. Specifically, for example, the rotational position information of the encoder 42 acquired by the acquisition process is the same in the first monitoring unit 26 and the second monitoring unit 27. Accordingly, the sticking abnormality cannot be detected unless the robot 10 is operated.

  Therefore, in order to detect the sticking abnormality, the controller 20 according to the present embodiment outputs a pulse signal PS1, PS2, PS3 from the first and second monitoring units 26, 27 as shown in FIG. The first diagnosis unit 28 and the second diagnosis unit 29 are provided.

  The first monitoring unit 26 outputs one pulse signal after completion of each of the three specific processes among the five processes for each calculation cycle. In the present embodiment, these specifying processes are an acquisition process, a speed calculation process, and a speed monitoring determination process. Further, in the case where no abnormality has occurred in the first monitoring unit 26, the time intervals of the temporally adjacent pulse signals among the pulse signals output after completion of each of the three specific processes are different from each other and determined in advance. The set time intervals Tα, Tβ, Tγ are set (see FIG. 5A).

  The second monitoring unit 27 outputs one pulse signal after completion of each of the three specific processes that are the same as those of the first monitoring unit 26 out of the five processes for each calculation cycle. In the present embodiment, the pulse width of the pulse signal output from the second monitoring unit 27 is set to be the same as the pulse width of the pulse signal output from the first monitoring unit 26. In addition, when no abnormality has occurred in the second monitoring unit 27, time intervals of pulse signals adjacent in time among pulse signals output after completion of each of the three specific processes are different from each other and determined in advance. The set time intervals Tα, Tβ, and Tγ are set.

  If the first diagnosis unit 28 determines that the time interval at which the pulse signal is input from the first monitoring unit 26 coincides with a predetermined first threshold time, the first diagnosis unit 28 maintains the first power shut-off unit 23 in a conductive state. On the other hand, when the first diagnosis unit 28 determines that the pulse signal is not input for a long period of time, that is, when it is determined that the time interval at which the pulse signal is input does not match the first threshold time, the first diagnosis unit 28 switches from the conduction state to the cutoff state. Thus, the first power shut-off unit 23 is switched.

  When the second diagnosis unit 29 determines that the time interval at which the pulse signal is input from the second monitoring unit 27 coincides with a predetermined second threshold time, the second diagnosis unit 29 maintains the second power shut-off unit 24 in the conductive state. On the other hand, when it is determined that the pulse signal is not input for a long period of time, the second diagnosis unit 29 switches the second power supply cutoff unit 24 so as to switch from the conduction state to the cutoff state. Thereby, even if a sticking abnormality occurs, the sticking abnormality is quickly detected so that the robot 10 is not operated.

  FIG. 4 shows the procedure of abnormality diagnosis processing executed by the first and second diagnosis units 28 and 29. In the present embodiment, the abnormality diagnosis process in the first diagnosis unit 28 and the abnormality diagnosis process in the second diagnosis unit 29 are the same. Therefore, in the present embodiment, the first diagnosis unit 28 will be described as an example.

  In this series of processing, first, in step S10, it is determined whether or not the pulse signal output from the first monitoring unit 26 has been input. In the present embodiment, if no abnormality has occurred in the first monitoring unit 26, after the activation of the controller 20, the pulse signal PS1 is output from the first monitoring unit 26 after the acquisition process shown in FIG. 3 is completed, and in step S10 A positive determination is made.

  If a negative determination is made in step S10, the process proceeds to step S11, and after the controller 20 is started, it is determined whether or not a predetermined time Tth has elapsed from the timing (reference timing) for which the negative determination is made for the first time in step S10. This process is a process for determining whether or not a sticking abnormality has occurred. That is, when a sticking abnormality occurs after the controller 20 is activated, the acquisition process is not completed, and the pulse signal PS1 is not output from the first monitoring unit 26.

  The specified time Tth is specifically the three time intervals (Tβ> of the pulse signals PS1, PS2, PS3 when no abnormality occurs in the first monitoring unit 26 shown in FIG. It may be set to a time longer than the maximum time Tβ among Tα> Tγ). More specifically, the specified time Tth may be set to a time equal to or longer than one calculation cycle, which is the total processing time of the five processes shown in FIG.

  If it is determined in step S11 that the specified time Tth has not elapsed, the process returns to step S10. On the other hand, if it is determined in step S11 that the specified time Tth has elapsed, the process proceeds to step S12 to diagnose that the first monitoring unit 26 has a sticking abnormality.

  If it is determined in step S10 that a pulse signal has been input, the process proceeds to step S13 to determine whether or not a pulse signal has been input. In the present embodiment, if no abnormality has occurred in the first monitoring unit 26, the pulse signal PS2 is output from the first monitoring unit 26 after the speed calculation process shown in FIG. 3 is completed, so that an affirmative determination is made in step S13. The

  If a negative determination is made in step S13, the process proceeds to step S14, and immediately after the transition from step S10 to step S13, it is determined whether or not a specified time Tth has elapsed from the timing when the negative determination is made for the first time in step S13. This process is a process for detecting a sticking abnormality. That is, when a sticking abnormality occurs after the acquisition process is completed, the speed calculation process is not completed, and thus the pulse signal PS2 is not output from the first monitoring unit 26.

  If it is determined in step S14 that the specified time Tth has not elapsed, the process returns to step S13. On the other hand, if it is determined in step S14 that the specified time Tth has elapsed, the process proceeds to step S12.

  If it is determined in step S13 that a pulse signal has been input, the process proceeds to step S15, and the time from the affirmative determination in step S10 to the affirmative determination in step S13 is measured by a counter and calculated as the first time T1. To do. In the present embodiment, the calculated first time T1 is stored in the memory of the controller 20.

  In subsequent step S16, it is determined whether or not the first time T1 coincides with the first determination time Tα. This process is a process for determining whether an abnormality in the processing time has occurred in the first diagnosis unit 28. The abnormality in the processing time is an abnormality in which the first time T1 is excessively long or excessively short with respect to the first determination time Tα. In this embodiment, when it is determined that “Tα−Δ ≦ T1 ≦ Tα + Δ” is satisfied, it is determined that the first time T1 coincides with the first determination time Tα. Here, Δ is a minute amount larger than zero. Further, the first determination time Tα is a predetermined value, and in this embodiment, the first determination time Tα is set to the time from the completion of the acquisition process to the completion of the speed calculation process.

  If it is determined in step S16 that they do not coincide with each other, the process proceeds to step S17 to diagnose that an abnormality in the processing time has occurred.

  If it is determined in step S16 that they match, the process proceeds to step S18 to determine whether or not a pulse signal has been input. In the present embodiment, if no abnormality has occurred in the first monitoring unit 26, the pulse signal PS3 is output from the first monitoring unit 26 after the speed monitoring determination process shown in FIG. 3 is completed, so an affirmative determination is made in step S18. Is done.

  If a negative determination is made in step S18, the process proceeds to step S19, and immediately after the transition from step S16 to step S18, it is determined whether or not a specified time Tth has elapsed from the timing when the negative determination is made for the first time in step S18. This process is a process for detecting a sticking abnormality. That is, when a sticking abnormality occurs after the speed monitoring determination process is completed, the speed monitoring determination process is not completed, and thus the pulse signal PS3 is not output from the first monitoring unit 26.

  If it is determined in step S19 that the specified time Tth has not elapsed, the process returns to step S18. On the other hand, if it is determined in step S19 that the specified time Tth has elapsed, the process proceeds to step S12.

  If it is determined in step S18 that a pulse signal has been input, the process proceeds to step S20, and the time from the affirmative determination in step S13 to the affirmative determination in step S18 is counted by a counter and calculated as the second time T2. To do. In the present embodiment, the calculated second time T2 is stored in the memory of the controller 20.

  In a succeeding step S21, it is determined whether or not the second time T2 coincides with the second determination time Tβ. This process is a process for determining whether an abnormality in the processing time has occurred in the first diagnosis unit 28. In this embodiment, when it is determined that “Tβ−Δ ≦ T2 ≦ Tβ + Δ” is satisfied, it is determined that the second time T2 coincides with the second determination time Tβ. The second determination time Tβ is a predetermined value. In the present embodiment, the second determination time Tβ is set to a time from the completion of the speed calculation process to the completion of the speed monitoring determination process. If it is determined in step S21 that they do not coincide with each other, the process proceeds to step S22 to diagnose that an abnormality in the processing time has occurred.

  If it is determined in step S21 that they match, the process proceeds to step S23 to determine whether or not a pulse signal has been input. In the present embodiment, if no abnormality has occurred in the first monitoring unit 26, the pulse signal PS1 is output from the first monitoring unit 26 after the acquisition process illustrated in FIG. 3 is completed, and thus an affirmative determination is made in step S23. .

  If a negative determination is made in step S23, the process proceeds to step S24, and immediately after the transition from step S21 to step S23, it is determined whether or not a specified time Tth has elapsed from the timing when the negative determination is made for the first time in step S23. This process is a process for detecting a sticking abnormality.

  If it is determined in step S24 that the specified time Tth has not elapsed, the process returns to step S23. On the other hand, if it is determined in step S24 that the specified time Tth has elapsed, the process proceeds to step S12.

  If it is determined in step S23 that a pulse signal has been input, the process proceeds to step S25, and the time from the affirmative determination in step S18 to the affirmative determination in step S22 is counted by a counter and calculated as the third time T3. To do. In the present embodiment, the calculated third time T3 is stored in the memory of the controller 20.

  In a succeeding step S26, it is determined whether or not the third time T3 coincides with the third determination time Tγ. This process is a process for determining whether or not a processing time abnormality has occurred. In this embodiment, when it is determined that “Tγ−Δ ≦ T3 ≦ Tγ + Δ” is satisfied, it is determined that the third time T3 coincides with the third determination time Tγ. The third determination time Tγ is a predetermined value. In the present embodiment, the third determination time Tγ is set to a time from the completion of the speed monitoring determination process to the completion of the acquisition process. If it is determined in step S26 that they do not match, the process proceeds to step S28, and it is determined that an abnormality in processing time has occurred.

  After completion of steps S17, S22, and S28, in step S29, it is determined whether a replacement abnormality has occurred. The switching abnormality is that at least two of the five processes shown in FIG. 3 are switched in either the first monitoring unit 26 or the second monitoring unit 27, and the order of the five processes is different from the predetermined order. It is an anomaly that becomes a thing. Specifically, when it is determined that the order of the time intervals of the pulse signals input from the first monitoring unit 26 does not match the order of the predetermined time intervals, the determination is made that the first monitoring unit 26 has been replaced and an abnormality has occurred. To do. Specifically, for example, when it is determined that the order of the first, second, and third times T1, T2, and T3 stored in the memory does not match the order of the first determination times Tα, Tβ, and Tγ, the second The monitoring unit 26 is switched to determine that an abnormality has occurred. In the present embodiment, even if a replacement abnormality actually occurs, it cannot always be determined in step S29 that a replacement abnormality has occurred.

  After step S29 or step S12 is completed, the process proceeds to step S30, and the first power shutoff unit 23 is switched from the conduction state to the cutoff state.

  In addition, when it determines with matching in step S26, it transfers to step S13. When a negative determination is made in step S13, the process proceeds to step S14, and immediately after the transition from step S26 to step S13, it is determined whether or not a specified time Tth has elapsed from the timing when the negative determination is made for the first time in step S13. Thereafter, when an affirmative determination is made in step S13, the process proceeds to step S15. In step S15, the time from the affirmative determination in step S25 until the affirmative determination in step S13 is counted by a counter and calculated as the first time T1.

  Incidentally, in the present embodiment, the determination times Tα, Tβ, Tγ used in the first diagnosis unit 28 correspond to “first threshold time”, and the determination times Tα, Tβ, Tγ used in the second diagnosis unit 29 are the same. This corresponds to “second threshold time”.

  FIG. 5 shows transitions of the respective pulse signals when the first monitoring unit 26 is normal and when the fixing is abnormal. In the example shown in FIG. 5, a sticking abnormality occurs immediately after the speed calculation process is completed and the pulse signal PS2 is output. For this reason, no pulse signal is input to the first diagnosis unit 28 thereafter. As a result, the first diagnosis unit 28 diagnoses that a sticking abnormality has occurred, and the first power cut-off unit 23 is switched to the cut-off state.

  The embodiment described in detail above has the following advantages.

  The first monitoring unit 26 outputs one pulse signal after each of the acquisition process, the speed calculation process, and the speed monitoring determination process for each calculation cycle. When no abnormality has occurred in the first monitoring unit 26, the time intervals of the pulse signals that are temporally adjacent to each other among the pulse signals that are output after completion of each of these processes are different from each other and are predetermined time intervals. Tα, Tβ, and Tγ are set. In addition, the second monitoring unit 27 outputs one pulse signal after each of the acquisition process, the speed calculation process, and the speed monitoring determination process for each calculation cycle. In the case where no abnormality has occurred in the second monitoring unit 27, time intervals of pulse signals that are temporally adjacent to each other among pulse signals output after completion of each of these processes are different from each other and are predetermined time intervals. Tα, Tβ, and Tγ are set.

  In this configuration, the first and second diagnosis units 28 and 29 have respective determination times Tα in which time intervals T1, T2, and T3 at which pulse signals are input from the first and second monitoring units 26 and 27 are predetermined. , Tβ, and Tγ are determined not to coincide with each other, it is determined that the processing time is abnormal in the first and second monitoring units 26 and 27. Then, the first and second diagnosis units 28 and 29 switch the first and second power supply cutoff units 23 and 24 so as to switch from the conduction state to the cutoff state. As a result, even when a single failure such as a sticking abnormality occurs in either the first monitoring unit 26 or the second monitoring unit 27, the abnormality can be detected quickly and the robot 10 can be prevented from operating. .

Second Embodiment
Hereinafter, the second embodiment will be described with reference to the drawings with a focus on differences from the first embodiment. In the present embodiment, as shown in FIG. 6, the first and second monitoring units 26 and 27 output a pulse signal after completion of each of the five processes for each calculation cycle. In the present embodiment, PS1, PS2, PS3, PS4, and PS5 are pulse signals output after completion of the acquisition process, position calculation process, speed calculation process, position monitoring determination process, and speed monitoring determination process.

  When there is no abnormality in the first and second monitoring units 26 and 27, the number of pulses of each of the pulse signals PS1, PS2, PS3, PS4, and PS5 is set different from each other and a predetermined number of pulses. Has been. In the present embodiment, the number of pulses of each pulse signal PS1, PS2, PS3, PS4, PS5 is 1, 2, 3, 4, 5 as shown in FIG.

  In the present embodiment, the time interval of the first pulse signal output after completion of each of the five processes is the same as each other and is set to a predetermined time interval TL as shown in FIG. Is set.

  This configuration is provided for detecting a switching abnormality even when the output intervals of the pulse signals are equal to each other. FIG. 7B illustrates the transition of the pulse signal when an abnormality occurs in which the position monitoring determination process and the speed monitoring determination process are switched. In this case, the first monitoring unit 26 will be described as an example. The order “1, 2, 3, 5, 4” of the number of pulses of the pulse signal input to the first diagnosis unit 28 has a predetermined number of pulses. It does not match the order “1, 2, 3, 4, 5”. For this reason, the pulse signal PS5 having five pulse numbers is input to the first diagnosis unit 28 in a situation where the pulse signal PS4 having four pulse numbers is to be input. Accordingly, the first diagnosis unit 28 determines that the order of the number of pulses of the input pulse signal does not match the order of the predetermined number of pulses, and switches the first power supply cutoff unit so as to switch from the conduction state to the cutoff state. 23 is switched.

  As described above, according to the present embodiment, even when the time intervals of the pulse signals output from the first monitoring unit 26 and the second monitoring unit 27 are equal to each other, the change of processing can be identified by the number of pulses. Therefore, it is possible to detect a change abnormality.

  Incidentally, in the second embodiment, when no abnormality has occurred in the first monitoring unit 26, among the first pulse signals output after completion of each of the five processes shown in FIG. The signal time intervals may be set to different time intervals. In this case, if the first monitoring unit 26 determines that the time interval of the first pulse signal output after completion of each of the five processes does not coincide with a predetermined threshold time, an abnormality in the processing time has occurred. It may be determined that The same applies to the second monitoring unit 27.

<Third Embodiment>
Hereinafter, the third embodiment will be described with reference to the drawings with a focus on differences from the second embodiment. In the present embodiment, as shown in FIG. 8A, in the case where no abnormality has occurred in the first and second monitoring units 26 and 27, the respective pulses of the respective pulse signals PS1, PS2, PS3, PS4 and PS5. The widths are different from each other and set to a predetermined pulse width. In the present embodiment, the pulse width of each pulse signal PS1, PS2, PS3, PS4, PS5 is set to W1, W2, W3, W4, W5.

  FIG. 8B illustrates the transition of the pulse signal when an abnormality occurs in which the position monitoring determination process and the speed monitoring determination process are switched. In this case, the first monitoring unit 26 will be described as an example. The pulse width order “W1, W2, W3, W5, W4” of the pulse signal input to the first diagnosis unit 28 has a predetermined number of pulses. The order does not match “W1, W2, W3, W4, W5”. For this reason, the pulse signal PS5 having the pulse width of W5 is input to the first diagnosis unit 28 in a situation where the pulse signal PS4 having the pulse width of W4 is to be input. Accordingly, the first diagnosis unit 28 determines that the order of the pulse widths of the input pulse signals does not match the order of the predetermined pulse widths, and switches the first power supply cutoff unit so as to switch from the conduction state to the cutoff state. 23 is switched.

  Also by this embodiment described above, the same effect as the second embodiment can be obtained.

  Incidentally, in the third embodiment, when there is no abnormality in the first monitoring unit 26, among the pulse signals output after completion of each of the five processes shown in FIG. The time intervals may be set to different time intervals. In this case, if the first monitoring unit 26 determines that the time interval of the pulse signal output after completion of each of the five processes does not coincide with the predetermined threshold time, the processing time is abnormal. You may judge. The same applies to the second monitoring unit 27.

<Other embodiments>
In addition, it can also implement by changing each said embodiment as follows.

  In the first embodiment, the robot 10 is not operated by switching the power shut-off unit from the conductive state to the shut-off state, but the present invention is not limited to this. Hereinafter, a description will be given with reference to FIG. In FIG. 9, the same components as those shown in FIG. 2 are given the same reference numerals for the sake of convenience.

  The controller 20 includes a signal blocking unit 50. The signal blocking unit 50 is provided on a signal transmission path for PWM signal transmission that connects the control unit 25 and the drive unit 21. The signal cutoff unit 50 includes a buffer IC 50a (for example, a three-state buffer) provided on the signal transmission path, and a switch 50b. The switch 50b switches an electrical connection state between the power source 51 and the buffer IC 50a to either a conduction state or a cutoff state by being energized. When the switch 50b is turned on, the signal transmission path is in a signal-passable state. As a result, the PWM signal output from the control unit 25 is transmitted to the drive unit 21 via the buffer IC 50a. On the other hand, when the switch 50b is turned off, the signal transmission path is turned off. As a result, the PWM signal output from the control unit 25 cannot pass through the buffer IC 50 a, and the PWM signal is not transmitted to the drive unit 21. As a result, all the high-side and low-side switches constituting the inverter of the drive unit 21 are turned off. As a result, power supply from the external power supply 40 to the motor 41 via the drive unit 21 is interrupted.

  In this configuration, the signal blocking unit 50 may be switched to the signal blocking state and the robot 10 may not be operated by switching the switch 50b to the blocking state by the first and second diagnosis units 28 and 29.

  In each of the above embodiments, the pulse signal may not be output after the speed monitoring determination process is completed.

  In the first embodiment, the first of which processing among the five processes of the acquisition process, the position calculation process, the speed calculation process, the position monitoring determination process, and the speed monitoring determination process is to be output is output. The monitoring unit 26 and the second monitoring unit 27 may be different from each other. In this case, each determination time used in the first diagnosis unit 28 and each determination time used in the second diagnosis unit 29 may be set to different values.

  In the second embodiment, the first monitoring unit 26 and the second monitoring unit 27 may have different time intervals for the first pulse signal output after completion of each of the five processes.

  In the second embodiment, the number of pulses of the pulse signal output after completion of each of the five processes may be different between the first monitoring unit 26 and the second monitoring unit 27.

  In the third embodiment, the pulse width of the pulse signal output after completion of each of the five arithmetic processes may be made different between the first monitoring unit 26 and the second monitoring unit 27.

  In the first embodiment, the first and second monitoring units 26 and 27 may monitor whether the control unit 25 is abnormal. In this case, when an abnormality of the control unit 25 is detected by the first and second monitoring units 26 and 27, the first and second power supply cutoff units 23 and 24 are shut off by the first and second monitoring units 26 and 27. You can switch to.

  -In the said 1st Embodiment, you may make one power-supply-cutoff part. In this case, the first monitoring unit, the second monitoring unit, the first diagnosing unit, and the second diagnosing unit are configured to switch the common power shut-off unit.

  The first and second power cutoff units 23 and 24 are not limited to contactors, and may be semiconductor switches such as IGBTs.

  In the first embodiment, the drive unit 21 may be accommodated in the housing 20a.

  The robot is not limited to a vertical articulated type, but may be a horizontal articulated type, for example.

  DESCRIPTION OF SYMBOLS 10 ... Robot, 20 ... Controller, 21 ... Drive part, 23, 24 ... 1st, 2nd power interruption part, 25 ... Control part, 26, 27 ... 1st, 2nd monitoring part, 28, 29 ... 1st, 2nd diagnostic part, 41 ... motor.

Claims (10)

A robot which comprises a robot having a plurality of rotating units and a motor for driving the rotating shaft of each rotating unit, and a rotation detecting unit for detecting rotational position information of the rotating shaft, and drives and controls the robot In the control device,
The rotational position information is configured to be input, and includes a first monitoring unit and a second monitoring unit that monitor presence or absence of abnormality of the robot based on the input rotational position information.
The first monitoring unit sequentially performs each of a plurality of processes based on the input rotational position information in a predetermined order for each calculation cycle,
The second monitoring unit sequentially performs each of the same processes as the plurality of processes performed by the first monitoring unit for each calculation cycle in the same order as a predetermined order performed by the first monitoring unit,
When the first monitoring unit determines that the processing result performed by the first monitoring unit is different from the processing result acquired from the second monitoring unit in the processing based on the input rotational position information, the robot system is abnormal. Is determined to have occurred,
When the second monitoring unit determines that the processing result performed by the second monitoring unit is different from the processing result acquired from the first monitoring unit in the processing based on the input rotational position information, the robot system is abnormal. Is determined to have occurred,
The first monitoring unit outputs a pulse signal before completion of all of the plurality of processes and after completion of at least one specific process among the plurality of processes,
The second monitoring unit outputs a pulse signal before completion of all the plurality of processes and after completion of at least one specific process among the plurality of processes,
When the pulse signal output from the first monitoring unit is configured to be input, and it is determined that the time interval at which the pulse signal is input does not match a predetermined first threshold time, the first monitoring unit A first diagnosis unit that determines that an abnormality has occurred in the
When the pulse signal output from the second monitoring unit is configured to be input, and it is determined that the time interval at which the pulse signal is input does not match a predetermined second threshold time, the second monitoring unit And a second diagnostic unit that determines that an abnormality has occurred in the robot control apparatus. In the processing based on the rotational position information, the first diagnosis unit is configured to output the pulse signal even when the processing result performed by the first monitoring unit is the same as the processing result performed by the second monitoring unit. If it is determined that the time interval at which the input is not equal to the first threshold time set in advance, it is determined that an abnormality has occurred in the first monitoring unit,
The second diagnosis unit is configured to output the pulse signal even when the processing result performed by the first monitoring unit and the processing result performed by the second monitoring unit in the processing based on the rotational position information are the same. 2. The robot control device according to claim 1, wherein when it is determined that a time interval at which is input does not coincide with the predetermined second threshold time, it is determined that an abnormality has occurred in the second monitoring unit. The first monitoring unit is configured to determine whether or not the robot is in a stopped state by determining whether or not the processing result performed by the first monitoring unit in the processing based on the rotational position information matches the processing result acquired from the second monitoring unit. To
When the robot is maintained in a stopped state, the second monitoring unit determines a mismatch between the processing result performed by itself in the processing based on the rotational position information and the processing result acquired from the first monitoring unit. The robot control apparatus according to claim 1 or 2, wherein The first diagnosis unit determines that the processing time of the first monitoring unit is abnormal when it is determined that the time interval at which the pulse signal is input does not match the first threshold time,
The said 2nd diagnostic part determines with the abnormality of the processing time of the said 2nd monitoring part having arisen, when it determines with the time interval in which the said pulse signal is input does not correspond with the said 2nd threshold time. The robot control apparatus according to any one of? Each of the first monitoring unit and the second monitoring unit outputs a pulse signal after completion of each of a plurality of specific processes among the plurality of processes,
In the case where no abnormality has occurred in the first monitoring unit, time intervals of pulse signals adjacent in time among the pulse signals output after completion of each of the plurality of specific processes are different from each other and determined in advance. Set to the specified time interval,
When no abnormality occurs in the second monitoring unit, time intervals of pulse signals adjacent in time among the pulse signals output after completion of each of the plurality of specific processes are different from each other and determined in advance. Set to the specified time interval,
When the first diagnosis unit determines that the order of the time intervals of the input pulse signals does not match the order of the predetermined time intervals, the order of the plurality of processes is changed in the first monitoring unit. Determine that it has occurred,
When the second diagnosis unit determines that the time interval order of the input pulse signals does not match a predetermined time interval order, the second monitoring unit may change the order of the plurality of processes. the robot control apparatus according to any one of claims judged to be occurring in claim 1-4. Each of the first monitoring unit and the second monitoring unit outputs a pulse signal after completion of each of a plurality of specific processes among the plurality of processes,
When no abnormality has occurred in the first monitoring unit, the number of pulses of the pulse signal output after completion of each of the plurality of specific processes is set to a different number and a predetermined number of pulses. And
In the case where no abnormality has occurred in the second monitoring unit, the number of pulses of the pulse signal output after completion of each of the plurality of specific processes is set to a different number and a predetermined number of pulses. And
When the first diagnosis unit determines that the order of the number of pulses of the input pulse signal does not match the order of the predetermined number of pulses, the order of the plurality of processes is changed in the first monitoring unit. Determine that it has occurred,
When the second diagnosis unit determines that the order of the number of pulses of the input pulse signal does not match the order of the predetermined number of pulses, the order of the plurality of processes is changed in the second monitoring unit. the robot control apparatus according to any one of claims judged to be occurring in claim 1-4. Each of the first monitoring unit and the second monitoring unit outputs a pulse signal after completion of each of a plurality of specific processes among the plurality of processes,
When no abnormality occurs in the first monitoring unit, each pulse width of the pulse signal output after completion of each of the plurality of specific processes is set to a different pulse width from each other. And
When no abnormality occurs in the second monitoring unit, each pulse width of the pulse signal output after completion of each of the plurality of specific processes is set to a different pulse width from each other. And
When the first diagnosis unit determines that the order of the pulse widths of the input pulse signals does not match a predetermined order of the pulse widths, the order of the plurality of processes is changed in the first monitoring unit. Determine that it has occurred,
When the second diagnosis unit determines that the order of the pulse widths of the input pulse signals does not match a predetermined order of the pulse widths, the second monitoring unit may change the order of the plurality of processes. the robot control apparatus according to any one of claims judged to be occurring in claim 1-4. A drive unit configured to be operable by being supplied with electric power from an external power source, and driving the motor with a control signal for driving control of the robot as an input;
A power supply cutoff unit that switches a power supply state from the external power source to the motor via the drive unit to either a power supply permission state or a power supply cutoff state,
The first diagnosis unit performs a switching operation of the power supply cutoff unit so as to switch from the power supply permission state to the power supply cutoff state when it is determined that the time interval at which the pulse signal is input does not coincide with the first threshold time. And
When the second diagnostic unit determines that the time interval at which the pulse signal is input does not coincide with the second threshold time, the second diagnostic unit switches the power supply cutoff unit to switch from the power supply permission state to the power supply cutoff state. The robot control device according to any one of claims 1 to 7 . The power supply cut-off unit is a power cut-off unit that switches an electrical connection state between the drive unit and the external power source to either a conductive state or a cut-off state,
Switching the power supply cutoff unit to switch from the power supply permission state to the power supply cutoff state means switching the power supply cutoff unit so as to switch the connection state of the power supply cutoff unit from the conduction state to the cutoff state. The robot control apparatus according to claim 8 , wherein the robot control apparatus is operated. Each of the first monitoring unit and the second monitoring unit, without switching the power supply cutoff unit from the power supply permission state to the power supply cutoff state, when the robot is maintained in a stopped state, The robot control apparatus according to claim 8 or 9 , wherein the presence or absence of an abnormality in the robot system is monitored.

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