JP7141939B2 - industrial controller - Google Patents

Description

The present invention relates generally to industrial controllers.

In general, the role of an industrial controller is to control a device to be controlled without delay by periodically executing a control program. Industrial controllers have hardware resources such as processors and memories, but the hardware resources required to play a role are less than those of general computers. The amount of hardware resources is smaller than that of general computers.

Memory is one of the hardware resources. For example, the technology disclosed in Patent Document 1 is known as a technology related to the use of memory. The technique disclosed in Patent Document 1 deletes data to be deleted from the stored data based on the data attribute when the free space is small.

JP-A-2005-18539

An industrial controller that executes, in addition to a control program, an information program (typically a plurality of information programs) that performs information processing including processing different from control of a controlled device is considered.

In this type of industrial controller, it is desirable to share memory between the control program and the information program from the viewpoint of resource saving. Specifically, for example, the control program operates at regular intervals, and in the operation writes a data set related to the controlled device into a memory area within the memory. The information program reads, at a predetermined reading frequency, a data set belonging to a range according to the reading frequency (i.e., the data set to be read this time) from the memory area (the read data set is read, for example, by a predetermined calculation by the information program). or sent to a higher system such as an analysis server).

In this kind of industrial controller, the execution of the control program is usually prioritized over the execution of the information program. This is because, as described above, the role of the industrial controller is to control the device to be controlled without delay (that is, it is important to maintain the real-time property). In each cycle, the control program overwrites any data set in the memory area with a new data set if the free space in the memory area is insufficient.

Information programs have a lower priority than control programs. Therefore, data reading processing in information processing may be delayed. For this reason, the data set in the memory area may be overwritten and the desired data set may not be obtained. It is desirable that the data set to be read is saved at least until the data read process, but if the free space in the memory area is insufficient, the control program has no choice but to overwrite the new data set.

By using the technique disclosed in Patent Document 1, it is possible to increase the free space in the memory area by deleting data, thereby reducing the possibility of overwriting. However, since data deletion is performed based on the attributes of the data itself, depending on the attributes of the dataset, all datasets belonging to the range that follows the read frequency may be deleted before the data read process. be.

Note that the problem that "the data set in the memory area may be overwritten and the desired data set may not be obtained" may occur regardless of the amount of memory capacity. For example, control programs are typically written without reliance on information programs coexisting on the industrial controller. Even if such a control program writes a data set to the memory, if the data set is not necessary for the control program, for the purpose of saving memory consumption, etc., it is necessary to determine whether the information program has acquired the data set. Regardless, overwriting the data set in memory with a new data set may be done.

In an industrial controller that controls a device to be controlled and has a processor and memory, the processor executes an OS (Operating System) and the memory includes a memory area in which data sets relating to the device to be controlled are written. The multiple programs on the OS include control programs and information programs. The control program performs control processing including control of the controlled device, acquisition of a data set related to the controlled device, and writing of the data set in a memory area. A set can be written to a memory area in which other data sets are stored and in an empty area. The information program reads the data set from the memory area and performs information processing. Writing of the control program to the memory area is executed at a predetermined cycle. The industrial controller has a management unit that manages the data set processed by the information program on the memory area before the processing.

According to the present invention, it is possible to increase the possibility that a data set to be read in the information processing of the information program exists in the memory of the industrial controller in which both the control program and the information program are executed.

1 shows a hardware configuration of a system including an industrial controller according to Example 1; 4 shows the software configuration of the industrial controller according to the first embodiment; 4 shows the structure of a data management table; 4 shows the structure of frequency data; 4 shows the processing flow of the control AP. 4 shows the flow of processing of the information AP. 4 shows the flow of scheduler processing. 4 shows the processing flow of the management unit. An example of sorting processing is shown schematically. An example of processing is shown schematically. An example of checking a data set belonging to a window is shown schematically. An example of read-impossible notification is shown schematically. Schematically illustrates frequency adjustment. Schematic representation of depletion time estimation and output. 4 shows the software configuration of an industrial controller according to a second embodiment;

In the following description, an "interface device" may be one or more interface devices. The one or more interface devices may be one or more of the same type of communication interface device or two or more of different types of communication interface devices.

Also, in the following description, "memory" may be one or more memory devices, typically a main memory device. At least one memory device in the memory may be a volatile memory device or a non-volatile memory device.

Also, in the following description, a "persistent storage device" is one or more persistent storage devices. A permanent storage device is typically a non-volatile storage device (for example, an auxiliary storage device), and more specifically, for example, an HDD (Hard Disk Drive) or SSD (Solid State Drive).

Also, in the following description, "storage" may be at least memory of memory and persistent storage.

Also, in the following description, a "processor" is one or more processor modules. The at least one processor module is typically a microprocessor device such as a CPU (Central Processing Unit), but may be another type of processor device such as a GPU (Graphics Processing Unit). At least one processor device may be single-core or multi-core. At least one processor module may be a processor core.

Further, in the following explanation, the processing may be explained with the subject of "program". As it occurs while in use, the subject of processing may be a processor (or a device, such as a controller, having that processor). A program may be installed on a device, such as a computer, from a program source. The program source may be, for example, a program distribution server or a computer-readable (eg, non-temporary) recording medium. Also, in the following description, two or more programs may be implemented as one program, and one program may be implemented as two or more programs.

Also, in the following description, the function may be described using the expression “kkk unit”, but the function may be realized by executing one or more computer programs by a processor. When a function is realized by executing a program by a processor, the defined processing is performed using a storage device and/or an interface device as appropriate, so the function may be at least part of the processor. good. A process described with a function as the subject may be a process performed by a processor or a device having the processor. The description of each function is an example, and multiple functions may be combined into one function, or one function may be divided into multiple functions.

Also, in the following description, information may be described using an expression such as "xxx table", but the information may be data of any structure. Therefore, the "xxx table" can be called "xxx information". Also, in the following description, the configuration of each table is an example, and one table may be divided into two or more tables, or all or part of two or more tables may be one table. may

Also, in the following description, a "dataset" is a single logical chunk of electronic data seen from a program such as an application program, for example, any of records, files, key-value pairs and tuples. It's okay.

Also, in the following description, an example of a control program is a control AP, and an example of an information program is an information AP. "AP" is an abbreviation for application program.

FIG. 1 shows the hardware configuration of a system including an industrial controller according to the first embodiment.

Analysis server 101 and industrial controller 109 are connected to information network 108 . Also connected to control network 118 are industrial controller 109 and one or more I/O modules 119 (an example of an I/O port). The information network 108 is a communication network used for information communication processing performed by the information AP (that is, communication processing different from transmission of control information). The control network 118 is a communication network used when control information is transmitted by the control AP. The information network 108 and the control network 118 may be networks of different types or networks of the same type (for example, both may be LANs (Local Area Networks)). Also, at least part of the information network 108 and at least part of the control network 118 may be integrated.

One or more peripherals 120 are connected to one or more I/O modules 119 . Peripherals 120 are at least one device such as a sensor and a drive. The I/O module 119 functions as a bus slot into which the peripheral device 120 is detachably mounted as required. A device to be controlled is connected to the I/O module 119 either through the peripheral device 120 or not. Controlled devices and I/O modules 119 can be 1:1, 1:many, many:1 and many:many. Also, some I/O modules 119 may be connected to the information network 108 in addition to the control network 118, i.e., some I/O modules 119 may be devices shared by the control AP and the information AP. may be

The analysis server 101 is an example of a host system of the industrial controller 109 . The analysis server 101 comprises an EPROM 201 , a CPU 202 , a main memory 203 , a peripheral control device 205 , a nonvolatile storage device 206 and a network interface (corresponding to the illustrated network I/F) 207 . Analysis server 101 is connected to information network 108 via network interface 207 .

The industrial controller 109 includes a memory 169 (e.g., EPROM 208 and main memory 210), a peripheral control device 212, an I/O control device 214, a non-volatile storage device 215, a network interface (corresponding to the illustrated network I/F) 213, and a CPU 209 connected thereto. The I/O control device 214 and network I/F 213 are examples of interface devices. The CPU 209 is an example of a processor.

A peripheral controller 212 is connected to a network I/F 213 , an I/O controller 214 , a nonvolatile memory device 215 and a bus 211 . A memory 169 and a CPU 209 are also connected to the bus 211 .

The EPROM 208 may store at least one of a control AP and an information AP in advance, or may store a program downloaded from a program source such as a program distribution server (not shown). Not only one control AP and one information AP installed in the industrial controller 109, but also a plurality of control APs and/or a plurality of information APs can be provided by setting resources that can be used by the industrial controller 109 for each program. can be installed.

The CPU 209 reads the control AP and the information AP stored in the EPROM 208 into the main memory 210 and executes them to control the operation of these control AP and information AP. For example, the CPU 209 controls the plurality of peripheral devices 120 via the peripheral controller 212 , the I/O controller 214 and the plurality of I/O modules 119 by executing the control AP. Peripherals 120 may be mapped 1:1 to I/O modules 119 .

FIG. 2 shows the software configuration of the industrial controller 109. As shown in FIG.

First, the outline of the industrial controller 109 is as follows.

In the industrial controller 109, the CPU 209 executes the control AP 114 and the information AP 115 as described above. Execute AP115. A data management table 281 is an example of the memory area of the memory 169 . In addition to the data management table 281, the memory 169 also stores frequency data 282 describing the frequency of reading, for example, the frequency of reading.

The control AP 114 performs control processing. The control process includes controlling a controlled device, acquiring a measurement data set (an example of a data set related to the controlled device) related to the controlled device, and writing the measured data set to the data management table 281. is. A measurement data set is a data set that includes one or more measured values (eg, temperature value, current value) respectively corresponding to one or more measurement items (eg, temperature, current) related to the control target device. Each of the one or more measurements for the controlled device is obtained via I/O module 119 and I/O controller 214 . At least one measured value included in the acquired measurement data set is typically a value measured by a sensor or the like, but for at least one measurement item, based on the time series of the measured values It may be an estimated value. In the control process, the control AP 114 can write the data set in the area where other data sets are stored and the empty area in the data management table 281 . For example, in the control process, if the free space of the data management table 281 is less than the first capacity (or regardless of the amount of free space), the control AP 114 transfers the obtained measurement data set to the data management table 281. Any measurement data set existing in the table 281 (for example, the oldest measurement data set) is overwritten. “The free space of the data management table 281 is less than the first capacity” means, for example, that the number of free records is less than 1 (that is, zero).

The information AP 115 reads data sets from the data management table 281 and performs information processing. For example, the information AP 115 reads from the data management table 281 a measurement data set belonging to a range according to the reading frequency indicated by the frequency data 282, and performs information processing as processing different from control of the control target device. The “processing different from control of the controlled device” may be, for example, registering or updating the frequency data 282, or other processing. Also, "measured data set belonging to a range according to the read frequency" is, for example, when the read frequency is "p seconds", at least one measured data set belonging to an interval of p seconds. Specifically, for example, when the cycle C is 0.5 seconds and the reading frequency is 1 second, two measurement data sets are written to the data management table 281 between one reading and the next reading. However, the “measurement data set belonging to the range according to the read frequency” may be the measurement data set that was acquired and written first among the two measurement data sets. In this embodiment, the information processing also includes sending the loaded measurement data set to the analysis server 101 .

The OS 286 includes a management unit 294 that manages the data set processed by the information AP 115 with respect to the data management table 281 before processing. The management unit 294 is, for example, a kernel. Note that the “management section” may be outside the OS 286 .

The following controls are performed by the OS 286 .
- The control AP 114 is executed at a predetermined cycle. The execution cycle of the control AP 114 is hereinafter referred to as "cycle C", and the x-th (x is a natural number) cycle C is referred to as "cycle Cx".
If the information AP 115 is executed in each cycle C after the execution of the control AP 114 ends, it will end by the next cycle regardless of whether the information processing will be completed by the next cycle.
The management unit 294 is executed in each cycle C from the end of execution of the control AP 114 to the start of execution of the information AP 115 .

In each cycle C, the management unit 294 performs management processing. The management process is a process of managing the data set processed by the information AP 115 so as not to disappear from the data management table 281 before the data set is processed. For example, management processing may include at least one of the following.
・Change the storage position of the data set processed by the information AP 115 on the data management table 281 before the processing (for example, save it to a predetermined area before the start of the processing of the information AP 115 and store it immediately before the start of processing of the information AP 115). be returned to the data management table 281 by ).
・If the control AP 114 preferentially writes data sets in the free space of the data management table 281 (overwrites only when there is no free space in the data management table 281), at least When the free space of the data management table 281 is less than the second capacity, deleting the target data set from among the plurality of data sets belonging to the reading frequency indicated by the frequency data 282 . Note that "the free space of the data management table 281 is less than the second capacity" means, for example, that the number of free records is less than one (that is, zero). The second volume may be the same as or different from the first volume.

In this way, the industrial controller 109 performs management processing between the end of execution of the control AP 114 and the start of execution of the information AP 115, for example, in a certain cycle Cn. As a result, even if the reading by the information AP 115 is delayed to the next cycle C(n+1), in the next cycle C(n+1), the control AP 114 can read the measurement data set that has not yet been read. A dataset is never overwritten by a new measurement dataset. Therefore, there is a high possibility that the data management table 281 of the industrial controller 109 in which both the control AP 114 and the information AP 115 are executed contains the measurement data set to be read in the information processing of the information AP 115 .

Details of the industrial controller 109 will be described below. In the following description, one control AP 114 and one information AP 115 are taken as an example for simplification of description. A plurality of information APs 115 may exist for one control AP 114 , and a plurality of control APs 114 may exist for one information AP 115 . Also, the industrial controller 109 is, for example, an SDC (Software-Defined Controller). The SDC is a controller that can flexibly add, change, or delete functions (here, the information AP 115) according to the host system (the analysis server 101 in this embodiment) without affecting the "control" of the controlled device. Also, the management process does not need to include increasing the free space by deleting data sets from the data management table 281, but the control AP 114 preferentially writes data sets in the free space of the data management table 281. If so, it is useful for the management process to include deleting the data set from the data management table 281 .

CPU 209 of industrial controller 109 executes OS 286 . A control AP execution unit 111 and an information AP execution unit 112 operate on the OS 286 . The control AP execution unit 111 is, for example, a runtime library, and operates together with the control AP 114 in response to calls from the control AP 114 . Information AP execution unit 112 is, for example, a so-called library, and operates together with information AP 115 in response to a call from information AP 115 .

In the industrial controller 109, the priority of the control AP 114 is higher than the priority of the information AP 115. That is, execution of the control AP 114 has priority over execution of the information AP 115 . This is because the role of the industrial controller 109 is to control the device to be controlled without delay (that is, it is important to maintain the real-time property).

OS 286 includes one or more APIs (Application Programming Interfaces), manager 294 and scheduler 295 . At least one of the one or more APIs may exist outside of OS 286 .

One or more APIs include, for example, shared API 289 and frequency API 293 . The shared API 289 is an example of a memory interface, and is an API for I/O to the shared memory area of the control AP 114 and the information AP 115 (in this embodiment, the memory area where the data management table 281 exists). In this embodiment, the shared API 289 consists of a write API 291 used for writing and a read API 292 used for reading. A write API 291 may be common to all control APs 114 and a read API 292 may be common to all information APs 115 . The frequency API 293 is used when registering, updating, or reading the frequency data 282 . Also, any API may be an API for at least one of the control AP 114 and the information AP 115 and may be used by the management section 294 . Also, the access from the management unit 294 to the memory 169 may be through a route other than the shared API 289 and the frequency API 293 .

The management unit 294 is a kernel that performs the management processing described above. That is, the management unit 294 is implemented as a kernel of the OS286.

A scheduler 295 controls execution of the control AP 114 , the information AP 115 and the manager 294 . Scheduler 295 also controls the execution of APIs.

The memory 169 stores the data management table 281 and frequency data 282 as described above.

The analysis server 101 includes a measurement database (corresponding to the illustrated measurement DB) 104 , a DB processing section 102 and an analysis section 103 .

The measurement DB 104 is a database that stores measurement data sets.

The DB processing unit 102 receives the measurement data set from the information AP 115 and stores the measurement data set in the measurement DB 104 .

The analysis unit 103 reads a measurement data set belonging to the analysis target range from the measurement DB 104 and performs analysis using the measurement data set.

FIG. 3 shows the structure of the data management table 281. As shown in FIG.

Each record of the data management table 281 stores one measurement data set. Each record stores an acquisition ID and one or more measured values respectively corresponding to one or more measurement items.

Acquisition ID is an ID according to at least one of period and measurement time. For example, an acquisition ID may be a combination of a period ID (eg, Cx) and a measurement time. By referring to the acquisition ID, in certain information processing, it is possible to specify which measurement data set is the measurement data set according to the reading frequency range.

In each record, each of the one or more measurements is a member of the measurement data set.

FIG. 4 shows the configuration of the frequency data 282. As shown in FIG.

Frequency data 282 indicates the read frequency. In this embodiment, the frequency data 282 is common to all information APs 115, but different frequency data 282 may be prepared for each information AP 115, or may be prepared for each measurement item.

FIG. 5 shows the flow of processing of the control AP 114 . S501 to S503 are processes included in the control process. At least S501 out of S501 to S503 is processing corresponding to a scanning operation, which will be described later.

The control AP 114, when activated by the scheduler 295, controls the controlled device (S501). The control AP 114 acquires a measurement data set related to the controlled device (S502). The control AP 114 calls the write API 291 (S 503 ), thereby writing the acquired measurement data set to the data management table 281 .

After completing S503, the control AP 114 stops until the start of the next period (until the scheduler 295 next activates) (S504).

FIG. 6 shows the processing flow of the information AP 115 .

When activated by the scheduler 295, the information AP 115 performs predetermined processing different from control of the controlled device. In this embodiment, as the processing, the information AP 115 calls the frequency API 293 (S601), thereby registering or updating the frequency data 282. FIG. Note that in S601, another process may be performed instead of or in addition to calling the frequency API 293. FIG.

The information AP 115 calls the read API 292 (S602), whereby the measured data set belonging to the range according to the read frequency indicated by the frequency data 282 registered or updated in S601 (that is, the measured data set to be read) is added to the data management table. Read from 281. Reading of the measurement data set is performed based on the start time of the current information processing and the acquisition ID in the data management table 281 . In S602, the measurement data set to be read is, for example, a measurement data set that follows the relationship between the reading frequency (for example, p seconds) and the period C (for example, q seconds (typically q≤p)) (for example, for p seconds). the most recent of the one or more acquired measurement data sets).

The information AP 115 transmits the measurement data set read in S602 to the analysis server 101 .

After completing S603, the information AP 115 stops until it is next activated by the scheduler 295 (S604).

In S602, in addition to the measurement data set to be read in the current information processing, past unread measurement data sets among the measurement data sets other than the current information processing (for example, the read target in the previous information processing). ) has not been read, the past unread measurement data set may be read in addition to the measurement data set to be read in the current information processing. In this case, all read measurement data sets are sent to the analysis server 101 in S603.

In addition, in S602, the measurement data set read by the read API 292 may be brought into a state in which a new measurement data set may be written by the information AP 115 or the read API 292 (for example, invalidation or may be deleted from).

Further, for example, when a plurality of information APs 115 exist, the data set read by the information AP 115 for each information AP 115 may be a part of the measurement data set, that is, the measured value corresponding to the predetermined measurement item. . All the measured values in the measurement data set may be read by each of the plurality of information APs 115 performing information processing. In this case, the measurement data set may be a collection of multiple data sets, and each data set may be one (or more) measurement values.

FIG. 7 shows the processing flow of the scheduler 295 .

If the cycle C has started (S701: Yes), the scheduler 295 executes (activates) the control AP 114 (S702).

When the control AP 114 ends (S703: Yes), the scheduler 295 executes (activates) the management unit 294 (S704).

The scheduler 295 executes (activates) the information AP 115 when the management unit 294 is terminated (S705: Yes) and the timing corresponds to the reading frequency indicated by the frequency data 282 (S706: Yes) (S707). The scheduler 295 determines whether or not it is the cycle C at certain intervals even during the execution of the information AP 115, and if it is the cycle C, once stops the processing of the information AP 115 and then executes the control AP (S702). The stopped information AP 115 resumes processing after execution of the management unit 294 (S705).

When the information AP 115 ends (S703: Yes), the process returns to S701. If it is not the start of cycle C (S701: No) and there is another information AP 115 to be executed (S706: Yes), the scheduler 295 executes the other information AP 115 (S707).

If the information AP 115 has not ended (S708: No) but cycle C has started (S709: Yes), the scheduler 295 stops the information AP 115 and executes the control AP 114 (S702).

FIG. 8 shows the processing flow of the management unit 294 . S801 and S802 are processes included in the management process.

When activated by the scheduler 295, the management unit 294 determines whether there is space in the data management table 281 (S801). If the result of determination in S801 is true (S801: Yes), the management unit 294 performs sorting processing or processing processing (S802). As a result, there is space in the data management table 281 in which a new measurement data set can be written in the next cycle C. FIG. In other words, overwriting of new measurement data sets in the next cycle C can be avoided. Note that the management unit 294 may copy the data set written in the fixed memory area by the control AP 114 to another memory area.

In this embodiment, the management unit 294 and the information AP 115 are periodically executed, and the management unit 294 is executed more frequently than the information AP 115 .

In this embodiment, the management unit 294, the control AP 114, and the information AP 115 are prioritized when they are executed at the same time, and the management unit 294 and the control AP 114 have higher priority than the information AP 115. FIG.

FIG. 9 schematically shows an example of sorting processing.

For example, in cycle Cn, the selection process is a process of selecting a measurement data set from a plurality of measurement data sets belonging to a range according to the reading frequency (for example, for the selected measurement data set, a flag indicating prohibition of overwriting by the control AP 114 is set. processing). Note that the selection process may include deleting from the data management table 281 measurement data sets other than the selected measurement data set among the plurality of measurement data sets (for example, the control AP 114 may If the data set is preferentially written to free space).

A specific example will be described with reference to FIG.

Assume that the read frequency is twice the cycle C. In this case, there will be two cycles between the end of one reading and the next reading, and thus two measurement data sets will be written.

Assume that the measurement data set is written in cycle C1 and the measurement data set is written in the next cycle C2. In this case, the latest measurement data set to be read is the measurement data set written in cycle C2. However, due to a delay in information processing (or some other reason), reading of the measurement data set written in cycle C2 fails. Assume that the data management table 281 has no free space due to the control processing in cycle C2.

In a comparative example, the cycles C3 and C4 are entered as they are. In this case, in cycle C3, the measurement data set written in cycle C1 is overwritten with a new measurement data set, but there is no problem since the measurement data set written in cycle C1 is not read. However, in cycle C4, the measurement data set written in cycle C2 is overwritten with a new measurement data set, so there is no object to be read. Therefore, in this embodiment, there are no measurement data sets to be sent to the analysis server 101, and as a result, the number of measurement data sets used for analysis is reduced.

On the other hand, in this embodiment, in each period C, when the control AP 114 ends, the management process runs. In the sorting process in the management process in cycle C2, the measurement data set written in cycle C2 is sorted out (furthermore, the measurement data set written in cycle C1 may be deleted). In the sorting process in the management process in cycle C3, the measurement data set written in cycle C2 is sorted out (furthermore, the measurement data set written in cycle C3 may be deleted). Therefore, in cycle C4, the measurement data set written in cycle C2 is not overwritten with a new measurement data set.

In this way, the management process includes a selection process that selects a data set from a plurality of data sets belonging to a range according to the reading frequency of the information AP 115, and the selected data set is controlled until the information AP 115 reads it. It is managed by the management unit 294 so that the AP 114 is not overwritten. As a result, even if the reading by the information AP 115 is delayed and the measurement data set to be read is not read and increases in the data management table 281, the possibility that the unread measurement data set to be read is overwritten can be reduced. can be done.

FIG. 10 schematically shows an example of processing.

The processing process is a process of processing two or more data sets among a plurality of data sets belonging to a range according to the reading frequency and writing the processed data sets into the data management table 281 . The processing may include deleting the two or more data sets from the data management table 281 (for example, the control AP 114 preferentially writes the data sets in the free space of the data management table 281). case).

A specific example will be described with reference to FIG. Here, for the sake of simplification of explanation, attention is paid to one measurement item (measurement item A). Also, in FIG. 10, it is assumed that the numerical values in the block corresponding to the measurement item A are the measured values corresponding to the measurement item A. In FIG.

Suppose there are 6 measurements (6 measurement data sets) in the range according to the reading frequency. In this case, the management unit 294 calculates the average of the six measured values belonging to the range according to the read frequency (an example of processing), and writes the calculated average value to the data management table 281 . According to this example, one post-processing measurement data set according to six measurement data sets is written to the data management table 281 . The processed measurement data set is the measurement data set to be read belonging to the range according to the reading frequency. Incidentally, as described above, the six measurement data sets that have been processed may be deleted from the data management table 281 .

In this way, even if the measurement data set to be read is not read due to a delay in information processing and is added to the data management table 281, the possibility that the unread measurement data set to be read is overwritten can be reduced. can be done.

Note that the processing is not limited to the calculation of the average value. Further, the measurement data sets that are the basis of processing may be all measurement data sets belonging to the range according to the reading frequency, or may be a part of the measurement data sets. Further, the same processing may be performed for all measurement items, or different processing may be performed. An example of the latter may be, for example, the following.
- For measurement item A, an average value of six measurement values may be calculated.
- For measurement item B, the maximum value of the six measurements may be selected and the other measurements may be deleted.
- For measurement item C, the minimum value of the six measurements may be selected and the other measurements may be deleted.
・The measurement data set after processing includes the calculated average value for measurement item A, the selected maximum value for measurement item B, and the selected minimum value for measurement item C. OK.

Further, in this embodiment, at least one of the processes described with reference to FIGS. 11 to 14 may be performed.

FIG. 11 shows schematically the checking of datasets belonging to a window.

For example, a window that is a unit time range is specified. The industrial controller 109 may be provided with a designation reception unit that receives the designation of the window. The designation receiving unit may be included in the management unit 294, or may be an interface (for example, API) prepared for receiving designation of windows. The window may be specified by a user (eg, a user of Information AP 115). The window may be common to all information APs 115, may be different for each information AP 115, or may be different for each measurement item. The window size may be the same as or different from the loading frequency. The window size is, for example, the same or smaller than the read frequency.

The management process may include checking whether the measurement data set belonging to the window of the range according to the reading frequency satisfies a predetermined anomaly condition. If the check result is true, the management process may include setting an abnormality flag ON (an example of abnormality information indicating an abnormality) as information read together with the measurement data set in information processing after the management process. As a result, in the information processing, an abnormality flag ON is sent to the information AP 115 together with the measurement data set to be read. The anomaly flag ON may be sent to the analysis server 101 together with the measurement data set.

As a result, even if the number of measurement data sets that are not to be read because the reading frequency is low relative to the cycle C is larger than the number of measurement data sets that are to be read, at least the information AP 115 and the host system (analysis server 101 in this embodiment) For one thing, it is possible to inform the situation about the device to be controlled.

FIG. 12 schematically shows an example of a read impossibility notification.

When a new data set is overwritten by the control AP 114 on an unread data set to be read in the data management table 281, read-impossible information indicating that the data set to be read cannot be read. An output may be provided in the industrial controller 109 to output. This makes it possible to indicate if the measurement data set to be read has been overwritten. Note that the output unit may be included in the management unit 294 or may be included in the shared API 289 . In addition, the unreadable information may be output to at least one of the information AP 115 and the host system (the analysis server 101 in this embodiment), or may be displayed on a user terminal (not shown) (for example, an administrator's information processing terminal). good too. In addition, the output unit may respond to an inquiry from a user (for example, an administrator) (inquiry as to whether or not there is a measurement data set that has become unreadable) and return unreadable information if any. good.

A specific example will be described with reference to FIG.

In the control process in a certain cycle C5, any unread measurement data set to be read (for example, the measurement data set written in each of the cycles C2 and C4) must be overwritten with a new measurement data set. If not (for example, if all the measurement data sets existing in the data management table 281 are unread measurement data sets to be read), any unread reading in the data management table 281 The target measurement data set (eg, the measurement data set written in period C2) will be overwritten by the control AP 114 in period C5 with a new data set. In this case, read-impossible information, which is information indicating that the read target measurement data set cannot be read, is output.

Note that read-disabled information may be output to the information AP 115 along with a response to reading by the information AP 115 (and the read-disabled information may be sent from the information AP 115 to the analysis server 101). Specifically, for example, the unreadable information may be stored in the memory 169 together with the acquisition ID corresponding to the measurement data set to be read overwritten with the new measurement data set. When there is reading by the information AP 115 and the target to be read in the reading is the measurement data set corresponding to the acquisition ID, the unreadable information is output along with the response to the reading by the information AP 115 . In this way, there is no need to separately output the unreadable information, and it can be output as a response to the reading.

FIG. 13 schematically shows frequency adjustment.

The industrial controller 109 may be provided with a frequency adjusting unit that adjusts the frequency by changing the reading frequency based on the free space in the data management table 281 . As a result, the relationship between the free space of the data management table 281, the period C, and the reading frequency can be appropriately maintained, thereby reducing the possibility of overwriting an unread measurement data set to be read. Note that the frequency adjustment unit may be included in the management unit 294 or may be included in the frequency API 293 . Further, the industrial controller 109 may be provided with an interface that accepts from a user (for example, an administrator) a setting as to whether or not to perform frequency adjustment by the frequency adjustment unit. Further, frequency adjustment may be performed by the management unit 294 after S801: No in FIG. 8 or after S802, as illustrated in FIG.

For frequency adjustment, at least one of the following may be applied.
The frequency adjustment is the exhaustion time, which is the time when the free space of the data management table 281 becomes less than the first capacity from the time series of the free space of the data management table 281 (for example, the time when there is no free space in the data management table 281). and lowering the frequency of reading prior to the exhaustion time. By reducing the reading frequency, information processing including reading occurs less frequently per unit time. It is possible to reduce the possibility that the read target measurement data set will be overwritten. Note that the time series of free space in the data management table 281 may be accumulated in the memory 169 by the management unit 294, for example.
- The frequency adjustment may include increasing the reading frequency when the free space of the data management table 281 is equal to or greater than the third capacity. If the free space of the data management table 281 is equal to or larger than the third capacity, there is no problem even if the number of unread measurement data sets to be read increases. It is possible to improve the speed at which the number of measurement data sets to be read decreases, thereby improving the usage efficiency of the data management table 281 . The third capacity may be the same as at least one of the first capacity and the second capacity, or may be a capacity different from both the first capacity and the second capacity. For example, the third volume can be a larger volume than the first volume and the second volume.

FIG. 14 schematically shows estimation and output of exhaustion time.

The industrial controller 109 may include a time estimating unit that estimates the exhaustion time from the time series of the free space in the data management table 281 and a time output unit that outputs the estimated exhaustion time to the user. "Outputting the depletion time to the user" may mean displaying or outputting the depletion time by voice, or transmitting information indicating the depletion time to the information processing terminal (e.g., computer) of the user (e.g., administrator). It's okay. Thereby, the user can know the estimated exhaustion time, and accordingly can take countermeasures such as adjusting the reading frequency. At least one of the time estimation unit and the time output unit may be included in the management unit 294, may be included in the frequency adjustment unit, or may be included in any API.

Example 2 will be described. At that time, the points of difference from the first embodiment will be mainly explained, and the explanations of the points in common with the first embodiment will be omitted or simplified.

FIG. 15 shows the software configuration of the industrial controller according to the second embodiment.

In the industrial controller 1509, each of the control AP executor 111 and the information AP executor 112 is a container following container-based virtualization. A management unit 1501 is a container containing a program for executing management processing. That is, in this embodiment, management processing is performed by the management unit 1501 that exists outside the OS 286, and the management unit 1501 operates as a container on the OS 286. FIG.

Although several embodiments have been described above, these are examples for explaining the present invention, and are not meant to limit the scope of the present invention only to these embodiments. The invention can also be implemented in various other forms.

For example, with respect to Examples 1 and 2, the following can be said. That is, the management function (sorting or processing) is separated from the information AP 115 and the priority of the management function is lower than the control AP 114 but higher than the information AP 115 . Specifically, for example, the management function is executed with priority over the information AP 115 (for example, executed immediately after the end of the management AP 114). Management functions may be implemented as a kernel or as a high priority container. The scheduler 295 operates the management function after the processing of the control AP 114 so that the information AP 115 can efficiently save the necessary measurement data sets.

Also, for example, the write API 291 may specify whether or not the measurement data set is compressible, and each record of the data management table 281 may store information (for example, a flag) indicating whether or not the measurement data set is compressible. If compressible, the write API 291 may compress the measurement data set and the compressed measurement data set may be written to the data management table 281 . Also, in this case, if the record storing the measurement data set to be read contains information indicating that compression is possible, the read API 292 decompresses the compressed measurement data set in the record, The measurement data set obtained is sent to the information AP 115 . By performing compression, it is possible to reduce the decrease in the free space of the shared memory area, and as a result, it is possible to reduce the possibility that the measurement data set will be overwritten.

Also, for example, at least some of the following may apply, for example, to at least one embodiment.

Industrial controller 109 may also be referred to as a sequence controller, motion controller, or programmable logic controller (PLC). In control-specific programming languages such as ladder logic (LD language), sequential function chart (SFC language), function block (FBD language), structured text (ST language), instruction list (IL language) Control contents are described. In some cases, the description in general-purpose programming language such as C language may be replaced with part or all of the description in ladder language or the like.

For the control AP 114 that controls the controlled object connected to the industrial controller 109, it is effective to use a control-specific programming language such as a ladder language. A ladder can be displayed, which is effective for monitoring the status of the device to be controlled. On the other hand, the information AP 115 is effective for information processing in such an industrial controller 109 (for example, complex arithmetic operations and information communication processing such as transmission/reception of information with SCADA, MES, and cloud systems). Such information processing may be difficult to program in a control-specific language, and may be described using a programming language used in the information communication field such as the so-called C language or Java (registered trademark) language. .

The control AP 114 needs to actually operate the peripheral device 120 including the motor etc. via the I/O module 119 etc., and operate the production system etc. appropriately. Therefore, the control AP 114 is required to reliably execute processing within a set time (real-time performance). The control AP 114 controls a device to be controlled (for example, a hardware module such as a device component, a device including one or more hardware modules, or a system including a plurality of devices) according to a command describing control details. Control. For example, in a control such as "actually operating a peripheral device 120 including a motor or the like via an I/O module 119 or the like to appropriately operate a production system or the like", a "production system" or a "production system configuration "at least one device" is a "controlled device". A device to be controlled is typically a device connected via an I/O control device 214 (an example of an interface unit) in the industrial controller 109 . The control target device may be controlled directly from the control AP 114 (for example, without going through the I/O module 119 or the peripheral device 120), or indirectly from the control AP 114 (for example, by controlling the I/O module 119 or the peripheral device 120). (via peripheral device 120). The language for controlling the controlled device is not limited to a programming language specific to control such as a ladder language, but may be written in a general-purpose programming language such as C language. A controlling program is the control AP 114 .

A control AP written in a ladder language or the like performs a "scan operation" that reads or writes (obtains or updates) the state of a control target device specified in the description in the ladder language or the like. This scanning operation must be performed at predetermined intervals, and this predetermined interval is called "scan time". The scan time relates to the calculation time of the control AP, and is sometimes called a "cycle time" because the calculation period for control or the calculation for control is repeatedly performed at predetermined intervals. A scan time corresponds to the period C.

The scan time increases as the number and types of controlled devices controlled by the industrial controller 109 increase, but it is important to scan the controlled devices within the scan time.

I/O ports are built into or connected to the industrial controller 109 . An I/O port may have an I/O module 119, an I/O unit, or the like. Hereinafter, an I/O port itself or a device having an I/O port (such as an I/O module or an I/O unit) may be collectively referred to as an "I/O port". The I/O port is connected to a device to be controlled, such as a belt conveyor, a limit switch, and an actuator (for example, a motor) in production equipment, and is used to control the operation of the device to be controlled. An I/O port is a digital or analog I/O port. For example, analog I/O ports are used to read and write measurement data sets containing voltages, currents, temperatures, etc. of devices controlled by industrial controller 109 .

An inverter unit or a CNC (Computerized Numerical Control) that receives control information transmitted from the I/O port of the industrial controller 109 based on the control AP 114 by wire or wirelessly controls the motion of the actuator. Real-time performance is required.

Controlling a controlled device means controlling the operation of an I/O port to which a controlled device is connected. In other words, the control AP 114 is a program that controls an I/O port to which a device to be controlled is connected, in other words, outputs control information of the device to be controlled to the I/O port to which the device to be controlled is connected ( Specifically, for example, it is a program that performs a scanning operation including output of the control information.

In such an industrial controller 109, in addition to controlling the device to be controlled, information processing (for example, complex arithmetic operations, information communication processing such as transmission and reception of information with SCADA, MES, and cloud systems) can be performed. think about. Such information processing may be difficult to program in the language specific to control described above, and can be described using a programming language used in the information processing field such as C language or Java (registered trademark) language. be. A program that executes such information processing is the information AP 115 .

An example of the difference between the control AP 114 and the information AP 115 will be described.

As described above, the control AP 114 is a program related to control of the I/O port of the industrial controller 109, and the information AP 115 performs information processing (for example, arithmetic operations and communication with the cloud, as described above). It is a program to do. The control AP 114 is written in a ladder, ST language, or the like, and has a higher real-time capability than general-purpose languages represented by java (registered trademark), python, and the like. The information AP 115 is written in a language represented by java (registered trademark), python, or the like, and is more suitable for information processing than ladder or the like. A language such as the C language, which has high real-time capability, is suitable for hardware control, and is also suitable for information processing, may be used for both the control AP 114 and the information AP 115 . A device to be controlled is connected to the industrial controller 109 via an I/O port, and the control AP 114 transmits control information of the device to be controlled to an analog or digital I/O port connected to the device to be controlled. Although it is a program that performs a scanning operation, including On the other hand, the information AP 115 is a program that does not access analog or digital I/O ports (excluding I/O ports that are permitted to be shared with the information AP 115) connected to the controlled device. In other words, the information AP is a program that performs information processing that does not include a scan operation (different from a scan operation) (that is, a program that does not perform a scan operation).

Control generally requires high real-time performance, and information processing generally requires high throughput. As the OS, there are generally a dedicated OS (real-time OS) as an OS for control and a general-purpose OS as an OS for information processing.

Here, hypothetically, considering recent technology in the general-purpose computer field, it is conceivable that the control AP is executed on a dedicated OS and the information AP is executed on a general-purpose OS. For this reason, the coexistence of control APs and information APs is usually considered to adopt virtual machine technology that emulates a set of computational resources in a computer (hardware as a set of physical computational resources). Specifically, for example, the hypervisor creates a virtual machine with a dedicated OS as a guest OS for the control AP, and creates a virtual machine with a general-purpose OS as a guest OS for the information AP. and the information AP may be executed in separate virtual machines with different OSs.

However, in the virtual machine technology, in addition to the guest OS in the virtual machine, there is a host OS that is the base of the virtual machine. As a result, it is conceivable that there are many objects to be managed and the management becomes complicated.

Even if a device is connected to a computer, not all control APs and information APs in the computer can easily recognize the device. For each virtual machine, processing for recognizing the device is required via the guest OS.

Therefore, it is conceivable to adopt as the OS 286 an OS having a real-time function capable of providing the required real-time performance (hereinafter referred to as a “real-time general-purpose OS” for convenience), although it is a system of general-purpose OS.

109... industrial controller

Claims (12)

An industrial controller that controls a controlled device and has a processor and memory,
The processor executes an OS (Operating System),
the memory includes a memory area in which a data set relating to the controlled device is written;
A plurality of programs on the OS are
performing a control process including control of the controlled device, acquisition of a data set related to the controlled device, and writing of the data set in the memory area; a control program for overwriting any existing data set in the memory area with the data set when the free space is less than the first capacity ;
an information program that performs information processing, which is processing including reading a data set belonging to a range according to the reading frequency from the memory area , and processing different from control of the controlled device ;
According to the OS,
Writing the control program to the memory area is executed at a predetermined cycle,
When the information program is executed in each cycle after the execution of the control program is completed, the information program is terminated by the next cycle regardless of whether the information processing is completed by the next cycle,
a management unit that is executed by the OS from the end of execution of the control program to the start of execution of the information program in each cycle ;
In each cycle, at least when the free space of the memory area is less than a second capacity, the management unit deletes the target data set among the plurality of data sets belonging to the range according to the reading frequency. management process including
An industrial controller characterized by: The management process selects a data set from a plurality of data sets belonging to a range according to the reading frequency of the information program, and deletes data sets other than the selected data set among the plurality of data sets from the memory area. including a sorting process that is a process,
the targeted dataset is a dataset other than the screened dataset
The industrial controller according to claim 1, characterized in that: The management process processes two or more data sets among a plurality of data sets belonging to a range according to the read frequency, deletes the two or more data sets from the memory area, and processes the processed data sets. to the memory area ,
The targeted datasets are the two or more datasets on which the processing was based.
The industrial controller according to claim 1, characterized in that: further comprising a designation reception unit that receives designation of a unit time range,
In the management process, when a data set belonging to a specified unit time range within a range according to the reading frequency of the information program satisfies a predetermined abnormal condition, the data set is read together with the data set in the information processing after the management process. The industrial controller according to claim 1, further comprising setting abnormality information indicating an abnormality as information to be received. further comprising a frequency adjustment unit that adjusts the frequency by changing the frequency of reading based on the free space of the memory area
The industrial controller according to claim 1, characterized in that: The frequency adjustment includes estimating a time when the free space of the memory area becomes less than the first capacity from the time series of the free space of the memory area, and lowering the reading frequency before the time. ,including
6. The industrial controller according to claim 5, characterized in that: The frequency adjustment includes increasing the read frequency when the free space of the memory area is equal to or greater than a third capacity.
6. The industrial controller according to claim 5, characterized in that: a time estimation unit for estimating a time when the free space of the memory area becomes less than the first capacity from the time series of the free space of the memory area;
a time output unit that outputs the estimated time to a user;
The industrial controller of claim 1, further comprising: a. Information indicating that when a new data set is overwritten by the control program on a data set to be read that has not been read by the information program in the memory area, the data set to be read cannot be read. The industrial controller of claim 1, further comprising an output unit that outputs certain unreadable information. 10. The industrial controller according to claim 9 , wherein said unreadable information is output to said information program accompanying a response to reading by said information program. the data set written to the memory area is a compressed data set by a memory interface that is an interface to the memory area;
The industrial controller according to claim 1, wherein the data set read from said memory area and sent to said information program is a data set decompressed by said memory interface. A data management method performed by an industrial controller controlling a controlled device and having a processor and a memory, comprising:
The processor executes an OS (Operating System),
the memory includes a memory area in which a data set relating to the controlled device is written;
Multiple programs on the OS
performing a control process including control of the controlled device, acquisition of a data set related to the controlled device, and writing of the data set in the memory area; a control program for overwriting any existing data set in the memory area with the data set when the free space is less than the first capacity ;
an information program that performs information processing, which is processing including reading a data set belonging to a range according to the reading frequency from the memory area , and processing different from control of the controlled device ;
The data management method includes:
writing the control program to the memory area at a predetermined cycle;
When the information program is executed in each cycle after the execution of the control program is completed, the information program is terminated by the next cycle regardless of whether the information processing is completed by the next cycle. death,
By executing the management unit executed by the OS from the end of execution of the control program to the start of execution of the information program in each cycle, at least the free space of the memory area is reduced to the second If the capacity is less than the capacity of the above, perform management processing including deleting the target data set among the plurality of data sets belonging to the range according to the read frequency
A data management method characterized by:

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