JP2007026241A - Abnormality monitoring method and controller using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect an abnormality of the control software of both a master apparatus and a slave apparatus, in a controller wherein the master apparatus and a plurality of the slave apparatuses are connected by a communication line. <P>SOLUTION: The master apparatus has: a monitoring data generation processing part 3 generating monitoring data changing in each control period of the master apparatus; and a slave apparatus monitoring processing part 4 monitoring monitoring data from the slave apparatus. The slave apparatus has: a monitoring data generation processing part 9 generating the monitoring data changing in a control period of the slave apparatus; and a master apparatus monitoring processing part 8 monitoring the monitoring data from the master apparatus. Each of the master apparatus and the slave apparatus detects the abnormality of the opposite apparatus by confirming the update of the monitoring data in each communication period. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an abnormality monitoring method for a control device in which a master device and a plurality of slave devices are connected via a communication line, and more particularly to an abnormality monitoring method and a control device using the abnormality monitoring method.

A control device in which a conventional master device and a plurality of slave devices are connected will be described with reference to the drawings.
FIG. 4 shows a system configuration diagram of the conventional example, and FIG. 5 shows a communication data frame of the conventional example.
Here, the master device generates operation data by the operation data generation processing unit 1 and transmits it to the slave device, and the slave device performs a processing operation based on the operation data transmitted by the operation data processing unit 6. At the same time, the slave device transmits data indicating its own operation state to the master device at the operation state data output unit 7, and the master device monitors the operation data of the slave device at the slave device operation state monitor unit. As described above, since only data related to driving is exchanged, it has not been possible to determine whether the counterpart device is operating correctly.

As a method for solving this, Patent Document 1 discloses a method of transmitting monitoring data in addition to operation data when transmitting data. Here, the following data transmission / reception is performed for each communication cycle. That is, the host device (operation means) updates the abnormality monitoring data and sends the operation data and abnormality monitoring data together to the lower device (control means), and the lower device transfers this abnormality monitoring data to another register. The data in this register is transmitted to the host device (operation means) in the next communication cycle. In parallel with this, the host device (operation means) checks the abnormality monitoring data returned from the lower device (control means), the lower device checks the abnormality monitoring data of the host device, and any abnormality monitoring data is If it has not been updated correctly since the previous time, it is determined that an abnormality has occurred in the counterpart device.

JP-A-10-315170

  In the conventional example, when an error such as a software runaway occurs in the master device, the slave device may send incorrect operation data to the slave station, and the slave device may continue operation with this incorrect operation data and cause a runaway accident. there were. In addition, when a similar abnormality occurs in the slave device, there is a problem that incorrect operation state data is transmitted from the slave station and the master station performs an incorrect operation.

  On the other hand, in Patent Document 1, abnormality monitoring data is also transmitted in addition to operation data, and the abnormality of the counterpart device can be detected by checking the abnormality monitoring data with the upper device and the lower device. However, although the communication software is normal, when an abnormality occurs in the control software, the monitoring data is transmitted as usual by the communication software, so that there is a problem that the system abnormality of each device cannot be detected.

  The present invention has been made in view of such problems, and provides means for reliably detecting an abnormality in a master device and a slave device in a control device in which a master device and a plurality of slave devices are connected via a communication line. For the purpose.

In order to solve the above problem, the present invention is configured as follows.
That is, in the invention according to claim 1,
In the control device where the master device and the slave device are connected via a communication line,
The master device includes a monitoring data generation processing unit that generates monitoring data that changes every control cycle of the master device, and a slave device monitoring processing unit that monitors monitoring data from the slave device,
The slave device includes a monitoring data generation processing unit that generates monitoring data that changes every control cycle of the slave device, and a master device monitoring processing unit that monitors monitoring data from the master device,
An abnormality of the counterpart device is detected by confirming the update of the monitoring data for each communication cycle.
According to a second aspect of the present invention, a control device using the abnormality monitoring method according to the first aspect is provided.

According to the present invention, since both the master device and the slave device update the monitoring data with their own control software and transmit the monitoring data for each communication cycle, it is possible to reliably detect the control software abnormality of the counterpart device.
In addition, the control device using this abnormality monitoring method can detect the abnormality of the counterpart device more reliably.

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

FIG. 1 is a system configuration diagram showing a first embodiment of the present invention, FIG. 2 is a communication data frame showing the first embodiment, and FIG. 3 is a data transmission / reception time chart showing the first embodiment.
In FIG. 1, the master device includes an operation data generation processing unit 1 that generates operation data of the slave station, a slave device operation state monitor unit 2 that monitors operation state data from the slave device, and monitoring data that generates its own monitoring data. A generation processing unit 3, a slave device monitoring processing unit 4 that monitors monitoring data from the slave device, and a communication interface unit 5 that communicates with the slave device. The slave device includes an operation data processing unit 6 that processes operation data from the master device, an operation state data output unit 7 that outputs its own operation state data, and a master device monitoring processing unit that monitors monitoring data from the master station. 8. A monitoring data generation processing unit 9 that generates its own monitoring data, and a communication interface unit 10 that performs communication with the master device.
In FIG. 2, the transmission data includes monitoring data of the master device in addition to the operation data, and the reception data includes monitoring data of the slave device in addition to the operation state data.
FIG. 3 shows the relationship between the control cycle of the master device, the control cycle of the slave device, the communication cycle of the network, and the monitoring data. The monitoring data is updated at the control cycle and data transmission / reception is performed at the communication cycle. Indicates.

Hereinafter, the operation will be described with reference to the drawings.
In FIG. 1, in the master device, operation data of the slave device is generated by the operation data generation processing unit 1 for each control cycle. In parallel with this, the monitoring data generation processing unit 3 updates its own monitoring data for each control cycle. Usually, updating is performed by incrementing by one for each control cycle. Next, the communication interface 5 transmits the operation data of the slave device and its own monitoring data to the slave station every communication cycle.
On the other hand, in the slave device, the operation data processing unit 6 performs a processing operation based on the operation data from the master device. At the same time, the operation state data output unit 7 generates operation state data of the slave device, and the monitoring data generation processing unit 9 updates the monitoring data for each control cycle. Similarly, the update is performed by incrementing by one for each control cycle. The communication interface 10 transmits its own operation state data and monitoring data to the master device every communication cycle.
The above is the data exchange. In parallel, the master device monitors the operation state data from the slave device by the slave device operation state monitor unit 2, and the monitoring data from the slave device is the slave device monitoring processing unit 4. Monitor with. The slave device monitoring processing unit determines that the slave device is abnormal when the monitoring data has not been updated normally since the previous time.
On the other hand, in the slave device, the master device monitoring processing unit 8 monitors the monitoring data from the master device, and similarly determines that the master device is abnormal when the monitoring data is not normally updated.
Here, a supplementary description will be given of the monitoring data update method. In the present invention, the monitoring data is updated at the control cycle of the device. In the operation of the device, the control software that controls internal functions and the communication software that controls communication with external devices generally operate independently. For this reason, when the monitoring data is updated by the communication software, the monitoring data is updated even when the control software of the device becomes abnormal, so that the abnormality of the device cannot be detected. In this respect, when the monitoring data is updated by the control software, it is possible to reliably detect an abnormality in the device.

System configuration diagram in the first embodiment Communication data frame in the first embodiment Transmission / reception time chart in the first embodiment System configuration diagram in the conventional example Communication data frame in the conventional example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Operation data generation process part 2 Slave apparatus operation state monitor part 3 Monitoring data generation process part 4 Slave apparatus monitoring process part 5 Communication interface part 6 Operation data process part 7 Operation state data output part 8 Master apparatus monitoring process part 9 Monitoring data generation Processing unit 10 Communication interface unit

Claims (2)

In the control device where the master device and the slave device are connected via a communication line,
The master device includes a monitoring data generation processing unit that generates monitoring data that changes every control cycle of the master device, and a slave device monitoring processing unit that monitors monitoring data from the slave device,
The slave device includes a monitoring data generation processing unit that generates monitoring data that changes every control cycle of the slave device, and a master device monitoring processing unit that monitors monitoring data from the master device,
An abnormality monitoring method characterized in that an abnormality of a counterpart device is detected by confirming update of the monitoring data for each communication cycle.   A control device using the abnormality monitoring method according to claim 1.

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