JP2009199155A - Control system and control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control system for controlling movement of a remote control type or autonomous operation type robot or the like, allowing certain detection of abnormality of the robot or the like and the control system, preventing continuation of the movement by inertia even when the robot or the like moves at high speed when the abnormality occurs to prevent a risk in the periphery, and preventing increase of weight and volume of the robot or the like not to deteriorate movement performance of the robot or the like. <P>SOLUTION: This control system has: a power control computer 1 performing power control, and transmitting an alive message at a prescribed period; a drive control computer 2 outputting a velocity instruction to a servo driver 5, and transmitting the alive message at the prescribed period; and a communication line 3 connecting the computers 1, 2. When one of the computers 1, 2 does not receive the alive message, a stop instruction is output to the servo driver 5, and thereafter power supply to a drive system is shut off. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a control system and a control method for controlling the operation of a remote operation type or autonomous operation type robot or the like.

  Conventionally, there has been proposed a control system for controlling the operation of a remote operation type or autonomous operation type robot. If the robot is autonomous, the control system installed in the robot will not only control drive commands to servo drivers that drive motors and actuators, but also autonomous behavior control, drive power control, status management, etc. Perform the function. In addition, when the robot or the like is a remote control type, the control system mounted on the robot or the like can be used for communication management, in addition to drive command control to the servo driver, autonomous behavior control, drive power control and status management, etc. Perform functions such as telemetry / command management.

  The control system is configured by one or a plurality of computers mounted on a robot or the like, and realizes the functions described above.

  In such operation control of a robot or the like, when some abnormality occurs in the robot or the like, in many cases, it is safest to stop the robot or the like quickly. However, if an abnormal state such as a failure occurs for some reason in the control system that controls the operation of the robot or the like, the operation of the robot or the like may not be controlled, and the robot or the like may run out of control. It can be a dangerous condition that damages the equipment.

  Conventionally, in order to prevent such a dangerous state, a watchdog timer (WDT) is provided in a computer constituting a control system, such as a “multiprocessor system monitoring circuit” described in Patent Document 1. ) Has been proposed.

  In this technique, a reset signal is periodically transmitted to the WDT by software of a computer constituting the control system. In this technique, when the control system is operating normally, the WDT is periodically reset. If the reset signal is not transmitted for a certain period of time due to a failure of the control system, etc., the WDT overflows, which is used as a trigger to shut off the drive system power supply and forcibly stop the robot, etc. It is supposed to let you.

JP-A-2-17548

  By the way, in the technique of adding a conventional watchdog timer (WDT), it is possible to detect an abnormality of the control system, but there is a problem that a failure of the WDT itself cannot be detected.

  Also, in this technology, when an abnormality of the control system is detected by WDT while the robot or the like is operating at high speed, the power of the drive system is immediately shut off and the motor of the robot or the like operating Or, the actuator is in a servo-off state, that is, in an uncontrolled state. Therefore, at this time, since the robot or the like continues to operate due to inertia until it stops due to energy loss such as friction, there is a risk of danger to the surroundings.

  In order to avoid such a danger, the power line of the motor is cut off at the same time, and the motor power line is disconnected from the servo driver and connected to the electric resistance, energy is consumed by the electric resistance, the motor is braked, and the motor is quickly stopped. There is technology to let you. However, when the operation of the robot or the like is fast, it is necessary to use a large electric resistance in order to absorb the inertial energy quickly. Therefore, the weight and volume of the robot or the like increase, and the operation performance of the robot or the like is reduced. There is a risk of deterioration.

  Therefore, the present invention has been made in view of the above circumstances, and is a control system and control method for controlling the operation of a remote operation type or autonomous operation type robot, etc. System abnormalities can be detected reliably, and if abnormalities occur, even if the robot is operating at high speed, it will prevent the robot from continuing to operate due to inertia and will be dangerous to the surroundings. It is an object of the present invention to provide a control system and a control method that prevent this, and does not increase the weight and volume of the robot or the like and do not deteriorate the operation performance of the robot or the like.

  In order to solve the above-described problems and achieve the object, the present invention has any one of the following configurations.

[Configuration 1]
The control system according to the present invention controls the power supply of the drive system and transmits an alive message at a fixed cycle and receives the alive message, and outputs a speed command or a position command to the servo driver to output a fixed cycle. A drive control computer that transmits and receives the alive message, and a communication line that connects these computers, and either the power control computer or the drive control computer is in a period longer than a certain period. If no alive message is received, each of these computers determines that an abnormality has occurred in any of the computers or the communication line, and outputs a stop command to the servo driver. Specially designed to cut off the power supply to It is an.

[Configuration 2]
The control method according to the present invention controls the power supply of the drive system by a power supply control computer that transmits an alive message and receives an alive message at a constant cycle, and transmits the alive message and receives an alive message at a fixed cycle. A speed command or position command is output to the servo driver by a computer, each computer is connected by a communication line, and either the power control computer or the drive control computer is alive for a period longer than a certain period. If no message is received, it is determined that one of the computers or a communication line error has occurred, and each of these computers outputs a stop command to the servo driver, and then supplies power to the drive system. Shut off the supply It is characterized in.

  In the control system according to the present invention having the configuration 1, when either the power control computer or the drive control computer does not receive the alive message for a period longer than a certain period, each of these computers Determines that an abnormality has occurred in any of the computers or communication lines, outputs a stop command to the servo driver, and then shuts off the power supply to the drive system, so the watchdog timer (WDT) Without using it, it is possible to detect abnormalities in the installed computer and stop the controlled object such as a robot with high reliability and safety.

  That is, in this control system, the drive control computer controls the servo driver so that the operation speed becomes zero, except for the case where the abnormality occurs in the drive control computer. After the time until the speed becomes sufficiently low, the power supply control computer shuts off the power supply to the drive system, minimizing idling after the drive power supply is cut off without using a large electrical resistance. It is possible to limit to the limit.

  In the control method according to the present invention having Configuration 2, when either the power supply control computer or the drive control computer does not receive the alive message for a period longer than a certain period, each computer Or the computer determines that a communication line abnormality has occurred and outputs a stop command to the servo driver by each of these computers, and then shuts off the power supply to the drive system, so a watch dog timer (WDT) It is possible to detect the abnormality of the installed computer without using the and to stop the controlled object such as the robot with high reliability and safety.

  That is, in this control method, the drive control computer controls the servo driver so that the operation speed becomes zero except for the case where the abnormality occurs in the drive control computer, and the operation speed of the robot or the like. After the time until it becomes sufficiently small, the power supply control computer cuts off the power supply to the drive system, thereby minimizing idle running after the drive power supply is cut off without using a large electrical resistance. It is possible to suppress it.

  That is, the present invention is a control system and control method for controlling the operation of a remote operation type or autonomous operation type robot or the like, and can reliably detect abnormalities in the robot or the like and the control system, When an abnormality occurs, even when the robot is operating at high speed, it is prevented from continuing to operate due to inertia to prevent danger to the surroundings. It is possible to provide a control system and a control method that do not increase the volume and do not deteriorate the operation performance of a robot or the like.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[Configuration of Control System According to the Present Invention]
FIG. 1 is a block diagram showing a configuration of a control system according to the present invention.

  The control system according to the present invention is a control system for controlling the operation of a remote operation type or autonomous operation type robot or the like, and as shown in FIG. 1, a power control computer (POW-C) 1 and A drive control computer (DRV-C) 2 is provided.

  The power supply control computer 1 controls the drive system battery 4 such as a robot to control the power supply of the drive system, transmits an alive message at a constant period, and receives an alive message from another computer.

  The drive control computer 2 outputs a speed command or a position command to the servo driver 5 such as a robot, transmits an alive message at a constant period, and receives an alive message from another computer. The servo driver 5 controls a motor such as a robot and an actuator 6.

  These computers 1 and 2 are connected to each other by a communication line (communication network) 3. The alive message is transmitted / received via the communication line 3.

  In addition, when the robot or the like is a fully autonomous operation type, there is an autonomous behavior control computer 7 that determines the operation of the robot or the like. On the other hand, in the case of a robot other than a fully autonomous type such as a remote control type robot, a remote control unit (OCU) (including a wireless or wired communication function part) and a wireless or wired communication function with a remote control unit are provided. There is a communication control computer (COM-C) 8 responsible. A communication device 9 is connected to the communication control computer 8. The communication device 9 transmits and receives operation signals and telemetry / command information to and from a remote control device (OCU) 10.

  The drive control computer 2 gives a speed command or a position command to a servo driver 5 that directly controls a motor such as a robot or an actuator 6 in accordance with a command sent from the autonomous behavior control computer 7 or the remote control device 10. The power supply control computer 1 controls ON / OFF of drive system power supplied to the servo driver 5.

  Various sensors 12 mounted on a robot or the like are connected to the other mounted computer 11. These computers 11 include a sensor control computer that controls the sensor 12 and performs signal processing.

[Control Method According to the Present Invention (Operation of Control System According to the Present Invention)]
The control method according to the present invention is executed by the control system according to the present invention configured as described above. That is, in this control system, when either the power supply control computer 1 or the drive control computer 2 does not receive an alive message for a period longer than a certain period, each of the computers 1, 1 2 determines that an abnormality has occurred in either of the computers 1 and 2 or the communication line 3, outputs a stop command to the servo driver 5, and then shuts off the power supply to the drive system.

  That is, the power supply control computer 1, the drive control computer 2, and the remote control device 10 have a function of transmitting and receiving an alive message in a predetermined format.

  FIG. 2 is a block diagram showing a format of an alive message transmitted / received in the control system according to the present invention.

  As an example, the alive message has a predetermined format as shown in FIG. 2, and includes a time tag corresponding to the time of transmission, the ID of the transmission source computer, and the message ID indicating the type of transmission message. Composed.

  Each of the computers 1 and 2 and the remote control device 10 broadcasts an alive message whose message ID is a message meaning an alive message in a network including the communication line 3 at a predetermined cycle.

  The time tag may be generated and broadcasted by one of the computers mounted on the robot or the like, and other computers that receive the time tag may generate and interpolate using their own clocks. It may be generated independently using only its own clock regardless of the time tag of the computer. In the case of a remote operation type robot, each computer may perform interpolation generation using its own clock based on the time tag sent from the remote operation device 10.

  Each computer 1, 2 knows the ID of the other computer and remote control device 10 and the correct transmission cycle of the alive message, and refers to the time tag of the message sent from each computer 1, 2 and remote control device 10 Then, it is confirmed whether or not the time tag is updated within the correct transmission cycle + α [seconds]. Note that α [second] is a grace period and is a predetermined numerical value. If the time tag is not updated within the transmission cycle + α [seconds], each of the computers 1 and 2 determines that an abnormality has occurred in the transmission source computer or the communication line 3.

  [Table 1] shows a method of detecting an abnormality occurring in each part of the configuration shown in FIG. 1 and a measure when an abnormality is detected. The abnormality detection is broadly classified into communication abnormality detection between the remote control device 10 and the robot, and abnormality detection of an internal computer such as the robot.

  Regarding abnormalities that occur outside the locations listed in [Table 1], the abnormalities are detected by a computer or the like to which the part is connected, and appropriate measures such as stopping the robot are taken according to the severity of the abnormalities. It is possible.

  First, in the case of A1 to A3 where a communication abnormality between the remote operation device 10 and the robot or the like is detected, the remote operation device 10 (including the communication function part), the remote operation device 10 and A communication line between robots and the like, and a communication control computer (COM-C) 8 are conceivable. An abnormality in a communication line means that a communication speed and a communication band necessary for normal communication are not obtained due to deterioration of the communication environment.

  In the case of the abnormality (A1) of the remote operation device 10 and the abnormality (A2) of the communication line, the communication control computer 8 can check either of them by checking the time tag of the alive message transmitted from the remote operation device 10. Detects that an abnormality has occurred.

  At this time, the communication control computer 8 broadcasts a message including a message ID indicating a communication abnormality between the remote control device 10 and the robot on the network. Upon receiving this message, the drive control computer (DRV-C) 2 performs control to reduce the operation speed of the robot or the like, and the power control computer (POW-C) 1 performs control to shut off the drive power, and the robot Etc. are stopped. In these cases (A1) and (A2), the control for cutting off the drive power supply is not an essential process.

  However, the timing at which the power supply control computer 1 cuts off the drive power supply is performed after a predetermined T [second] has elapsed since the power supply control computer 1 received the message. The predetermined T [seconds] is set to be longer than the time until the operation speed becomes sufficiently low after the robot or the like is operating at a high speed, thereby avoiding the operation part of the robot or the like from idling at a high speed. be able to.

  In the communication abnormality detection between the remote control device 10 and the robot or the like, if the abnormality occurrence location is the communication control computer 8 (A3), the communication that should be received by the power supply control computer 1 and the drive control computer 2 Since the alive message from the control computer 8 is not updated within a predetermined time, it is detected that the communication control computer 8 is abnormal.

  At this time, the drive control computer 2 performs control to reduce the operation speed of the robot or the like to 0, and the power control computer 1 performs control to shut off the drive power after a predetermined T [second] has elapsed since the abnormality was detected. As a result, the operation of the robot or the like is stopped. In this case (A3), the control for cutting off the drive power supply is not an essential process.

  Next, consider a case (B1 to B5) in which an internal communication abnormality such as a robot is detected. In this case, as shown in [Table 1], the locations where an abnormality has occurred are classified into a communication control computer 8, a power supply control computer 1, a drive control computer 2, another computer 11, and a communication line (network) 3. Among these, when an abnormality occurs in the communication control computer 8 (B1), it is the same as the case of (A3) described above.

  When an abnormality occurs in the power supply control computer 1 (B2), this is detected by the drive control computer 2, and the drive control computer 2 performs control to reduce the operation speed of the robot or the like. In this case, an abnormality has occurred in the power supply control computer 1, so that the power supply is generally not cut off. However, the operation of the robot or the like is stopped by the control by the drive control computer 2 to set the operation speed to zero. The

  When an abnormality occurs in the drive control computer 2 (B3), it is detected by the power supply control computer 1, and immediately after the detection, the drive power supply is controlled to be cut off. In this case, since an abnormality has occurred in the drive control computer 2, there is a possibility that the drive system power supply may be cut off while the robot or the like is operating. There is a possibility that the motor and the actuator 6 of the above will idle.

  When an abnormality occurs in the other computer 11 (B4), if it is determined in advance that it is desirable to stop the robot or the like for safety in consideration of the function of the computer 11, the drive control computer 2 Control is performed to reduce the operation speed of the robot, etc., and the power control computer 1 performs control to shut off the drive power supply after a predetermined T [second] has elapsed since the abnormality was detected, thereby stopping the operation of the robot, etc. .

  When an abnormality occurs in an internal communication line (network) 3 such as a robot (B5), each of the computers 1 and 2 cannot receive an alive message from any other computer. It is recognized that an abnormality has occurred in another computer. At this time, the drive control computer 2 performs control to reduce the robot operation speed to 0, and the power supply control computer 1 performs control to shut off the drive power supply after a predetermined T [seconds] has elapsed since the abnormality was detected. As a result, the operation of the robot or the like is safely stopped.

  With the above operation, even if any abnormality occurs in the remote control device 10, each computer 1, 2 or the communication line 3, the operation of the robot or the like can be performed reliably without using the watchdog timer (WDT). And it becomes possible to stop safely.

[Other Embodiments]
In the computer constituting the control system according to the present invention, the power supply control computer 1 and the drive control computer 2 may be separate computers, and need not be separate computers for each function as described above. For example, the power supply control computer 1 may also serve as the communication control computer 8.

  Each of the computers 1 and 2 and the communication line 3 may have a redundant configuration in order to improve reliability. The communication line 3 is not limited to a bus format represented by Ethernet (registered trademark), and any configuration may be used as long as the computers 1 and 2 are connected to each other.

  The alive message is not limited to being transmitted alone, but may also be used as a message for an application that is normally transmitted and received between computers for the operation of a robot or the like.

It is a block diagram which shows the structure of the control system which concerns on this invention. It is a block diagram which shows the format of the alive message transmitted / received in the control system which concerns on this invention.

Explanation of symbols

1 Power control computer (POW-C)
2 Drive control computer (DRV-C)
3 Communication line 4 Drive system battery 5 Servo driver

Claims (2)

A power control computer that performs power control of the drive system, transmits an alive message at a fixed period, and receives the alive message;
A drive control computer that outputs a speed command or a position command to the servo driver, transmits an alive message at a fixed period, and receives the alive message;
A communication line connecting the computers,
When any one of the power control computer and the drive control computer does not receive the alive message for a period longer than a certain period, each of the computers is one of the computers, or A control system that determines that an abnormality has occurred in the communication line, outputs a stop command to the servo driver, and then shuts off power supply to the drive system. Power supply control of the drive system is performed by a power supply control computer that sends alive messages and receives alive messages at regular intervals,
The drive control computer that sends alive messages and receives alive messages at regular intervals causes the servo driver to output a speed command or position command,
Each computer is connected by a communication line;
If any one of the power control computer or the drive control computer does not receive the alive message for a period longer than a certain period, either one of the computers or the communication line A control method characterized by discriminating that an abnormality has occurred, causing each of these computers to output a stop command to the servo driver, and then shutting off the power supply to the drive system.

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