JP2018206362A - Process analysis apparatus, process analysis method, and process analysis program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique for accurately modeling a causal relationship between a plurality of mechanisms constituting a manufacturing line. A process analysis apparatus according to one aspect of the present invention is for controlling a first acquisition unit that acquires a plurality of status data regarding the status of a plurality of mechanisms that configure a manufacturing line, and an operation of the manufacturing line. A second acquisition unit that acquires a control program of the above, a first analysis unit that specifies a connection state between the plurality of mechanisms by analyzing the acquired plurality of state data, and analyzes the acquired control program. By doing so, the causal effect between the plurality of mechanisms in the process performed on the manufacturing line based on the second analysis unit that specifies the order relationship of the plurality of mechanisms, and the connection state and the order relationship that are specified respectively. A relationship specifying unit that specifies a relationship. [Selection diagram] Figure 1

Description

  The present invention relates to a process analysis apparatus, a process analysis method, and a process analysis program.

  A production line in a factory or the like is composed of a plurality of mechanisms such as a conveyor and a robot arm. If an abnormality occurs in any of the mechanisms of this production line, the production of the product is stopped, which may cause great damage. For this reason, in factories and the like, maintenance staff periodically visit the production line to check whether an abnormality has occurred or whether there is a precursor.

  When an occurrence or a sign of an abnormality is detected in the production line, there may be a true cause of the abnormality in a mechanism before the mechanism in which the abnormality is detected. Therefore, in order to identify the cause of the true abnormality, it is important to understand the causal relationship of each mechanism in the production line. However, since the number of mechanisms constituting the production line increases and the operating conditions of each mechanism can change from day to day, it is difficult to accurately grasp the causal relationship of all the mechanisms.

  For this reason, conventionally, a skilled maintenance worker grasps the causal relationship between a plurality of mechanisms constituting a production line based on his / her experience and intuition, and detects an abnormality occurring in the production line or its precursor. It was. In order to allow unskilled maintenance personnel to perform such maintenance work, it has been desired to develop a technique for visualizing the causal relationship between a plurality of mechanisms constituting the production line.

  Therefore, Patent Document 1 proposes a method of modeling a relationship between manufacturing apparatuses in a manufacturing line by analyzing signals exchanged between a plurality of manufacturing apparatuses and a control apparatus. Specifically, feature quantities are calculated from a plurality of acquired signals, and the generation order of the plurality of signals is extracted. Then, a causal structure between the signals is created based on the correlation between the feature quantities and the signal generation order. Thereby, in the method proposed by Patent Document 1, the relationship between the manufacturing apparatuses in the manufacturing line can be modeled.

JP 2009-064407 A

  According to the method of Patent Document 1, a causal relationship between a plurality of mechanisms constituting a production line can be automatically modeled. However, since the production line repeats the same operation, it is possible to specify the relative order relationship of each mechanism from the signal generation order, but to identify which signal (mechanism) is the starting point of the operation. It was difficult. For example, when the production line includes three mechanisms A1, A2, and A3 and operates in the order of mechanism A1, mechanism A2, and mechanism A3, the mechanism A1 operates in the conventional method. It was difficult to identify the starting point of Therefore, in the method of Patent Document 1, there is a possibility that signals as starting points are mistaken and the causal relationship of a plurality of mechanisms cannot be accurately modeled.

  In one aspect, the present invention has been made in consideration of such points, and an object of the present invention is to provide a technique for accurately modeling a causal relationship between a plurality of mechanisms constituting a production line. is there.

  The present invention employs the following configuration in order to solve the above-described problems.

  That is, the process analysis apparatus according to one aspect of the present invention includes a first acquisition unit that acquires a plurality of state data related to the states of a plurality of mechanisms that constitute a production line, and a control for controlling the operation of the production line. A second acquisition unit that acquires a program; a first analysis unit that identifies a connection state between the plurality of mechanisms by analyzing the acquired state data; and an analysis of the acquired control program Based on the second analysis unit that identifies the order relationship of the plurality of mechanisms, and the connection state and the order relationship that are identified respectively, the causal relationship between the plurality of mechanisms in the process that is performed on the production line is determined. A relationship specifying unit for specifying.

  In the above configuration, the connection state between the plurality of mechanisms is specified based on a plurality of state data regarding the states of the plurality of mechanisms constituting the production line. Further, an order relationship between a plurality of mechanisms is specified based on a control program for controlling the production line. And the causal relationship between several mechanisms in the process implemented in a manufacturing line is specified by integrating the connection state and order relationship which were each identified. Here, the control program defines the operation of each mechanism. Therefore, the order relation of each mechanism can be specified appropriately by using the control program. Therefore, according to the said structure, the causal relationship between the some mechanism which comprises a manufacturing line can be modeled correctly.

  In addition, the manufacturing line should just be able to manufacture a certain thing, may be comprised with a some apparatus, and may be comprised with one apparatus, such as a packaging machine. Moreover, each mechanism should just be able to implement a certain process of a manufacturing process. Each mechanism may be, for example, a conveyor, a robot arm, a servo motor, a cylinder (such as a molding machine), a suction pad, a cutter device, and a seal device. Moreover, each mechanism may be a composite apparatus such as a printing machine, a mounting machine, a reflow furnace, and a board inspection apparatus. Furthermore, each mechanism is not limited to a device with some physical operation as described above, for example, a device that detects some information by various sensors, a device that acquires data from various sensors, and some information from the acquired data. A device that performs internal processing such as a device that detects data and a device that processes acquired data may be included. One mechanism may be composed of one or a plurality of devices, or may be composed of a part of the device. When one mechanism is configured by a part of the apparatus, the plurality of mechanisms may be configured by one apparatus. When the same apparatus performs a plurality of processes, each may be regarded as a separate mechanism. For example, when the same apparatus performs the first process and the second process, the apparatus that performs the first process is regarded as the first mechanism, and the apparatus that performs the second process is the second process. It may be regarded as a mechanism.

  The state data may include any kind of data regarding the state of each mechanism constituting the production line. The state data may be composed of data obtained from a measuring device such as one or a plurality of sensors and cameras. Further, the status data may be data obtained from the measuring device as it is, or data obtained by applying some processing to data obtained from the measuring device such as position data obtained from image data. It may be.

  The control program may include any type of program that controls the operation of each mechanism constituting the production line. The control program may be composed of one program or a plurality of programs.

  The connection state expression method is not particularly limited as long as it can indicate a connection between a plurality of mechanisms, and may be appropriately determined according to the embodiment. The connection state may be expressed by, for example, the strength of the relationship (for example, the correlation coefficient indicating the correlation), the presence / absence of the relationship, the change in the relationship, and the like. Note that the change in the relationship may be indicated by, for example, a time-series difference (change amount) of the relationship expressed by the strength or presence of the relationship.

  In the process analysis apparatus according to the one aspect, the relationship specifying unit may output directed graph information indicating a causal relationship between the specified mechanisms. According to this configuration, even the unskilled maintenance staff can easily grasp the causal relationship between the plurality of mechanisms constituting the production line by the output directed graph information.

  In the process analysis apparatus according to the above aspect, the first analysis unit may construct undirected graph information indicating a connection state between the plurality of specified mechanisms, and the relationship specifying unit may include the undirected graph information. The directed graph information may be created by applying the order relation to the. According to the said structure, the directed graph information which shows the causal relationship between several mechanisms can be produced appropriately.

  In the process analysis apparatus according to the above aspect, the first analysis unit (1) calculates a feature amount from the state data of each case, and (2) a correlation coefficient or a partial correlation coefficient between the feature amounts. The connection state between the plurality of mechanisms may be specified by calculating. According to the said structure, the connection state between several mechanisms can be specified appropriately.

  In the process analysis apparatus according to the one aspect, the second analysis unit specifies an order relation of the plurality of mechanisms based on log data obtained by operating the manufacturing line using the control program. May be. According to this configuration, it is possible to appropriately specify the order relationship between a plurality of mechanisms.

  In the process analysis apparatus according to the above aspect, the second analysis unit (1) constructs an abstract syntax tree from the control program, and (2) uses variables and conditional branches related to the mechanisms from the constructed abstract syntax tree. (3) Obtain log data when the production line is operated normally using the control program, and (4) Refer to the obtained log data and execute the conditional branch execution result. The order relation of the plurality of mechanisms may be specified by ordering the variables based on the above. According to this configuration, it is possible to appropriately specify the order relationship between a plurality of mechanisms.

  In the process analysis apparatus according to the above aspect, the second analysis unit (1) constructs an abstract syntax tree from the control program, (2) extracts variables related to the mechanisms from the constructed abstract syntax tree, (3) Based on the constructed abstract syntax tree, the dependency relationship of the variables in the processing of the control program is specified. (4) Based on the specified dependency relationship, the order relationship of the plurality of mechanisms is specified. Also good. According to this configuration, it is possible to appropriately specify the order relationship between a plurality of mechanisms.

  In the process analysis apparatus according to the above aspect, the step of (3) identifying the dependency relationship of the variables in the processing of the control program based on the constructed abstract syntax tree includes a control flow from the constructed abstract syntax tree. You may include the step which produces | generates a graph, and the step which specifies the dependence relationship of the extracted said variable based on the said produced | generated control flow graph. According to this configuration, it is possible to appropriately specify the order relationship between a plurality of mechanisms.

  In the process analysis apparatus according to the above aspect, the state data of each case includes torque, speed, acceleration, temperature, current, voltage, air pressure, pressure, flow rate, position, dimensions (height, length, width) and It may be data indicating at least one of the areas. The control program is described using at least one of a ladder diagram language, a function block diagram language, a structured text language, an instruction list language, a sequential function chart language, and a C language. May be. According to the said structure, the process-analysis apparatus which can handle various kinds of data and programs can be provided.

  In the process analysis apparatus according to the above aspect, the first analysis unit may identify connection states between the plurality of mechanisms by statistically analyzing the acquired plurality of state data. According to the said structure, the connection state between several mechanisms can be specified appropriately.

  In the process analysis apparatus according to the above aspect, the first analysis unit may specify the strength of the relationship between the plurality of mechanisms as the connection state. According to the said structure, the connection state between several mechanisms can be specified appropriately.

  The process analysis apparatus according to the one aspect includes a third acquisition unit that acquires mechanism data regarding at least one of a relative positional relationship of apparatuses included in each of the plurality of mechanisms and an order in which the apparatuses are involved in the process; A third analysis unit that analyzes the acquired mechanism data and identifies the process model indicating the order relationship of the plurality of mechanisms by modeling the process performed in the manufacturing line; Good. And the said relationship specific | specification part may specify the causal relationship between these several mechanisms in the process implemented in the said manufacturing line based on the said connection state, the said order relationship, and the said process model which were each identified. . According to the said structure, the causal relationship between the some mechanism which comprises a manufacturing line can be modeled more correctly by further utilizing the knowledge of the specified process model.

  In addition, as another form of the process analysis apparatus according to each of the above embodiments, an information processing method that realizes each of the above configurations, a program, a computer in which such a program is recorded, or the like It may be a storage medium that can be read by an apparatus, a machine, or the like. Here, the computer-readable recording medium is a medium that stores information such as programs by electrical, magnetic, optical, mechanical, or chemical action.

  For example, in the process analysis method according to one aspect of the present invention, a computer acquires a plurality of state data relating to states of a plurality of mechanisms constituting the production line, and a control for controlling the operation of the production line. A step of acquiring a program; a step of identifying a connection state between the plurality of mechanisms by analyzing the acquired plurality of state data; and a plurality of mechanisms by analyzing the acquired control program And a step of identifying a causal relationship between the plurality of mechanisms in a process performed on the production line based on the identified connection state and the ordered relationship, respectively. It is a processing method.

  In addition, for example, the process analysis program according to one aspect of the present invention is configured to control the operation of the manufacturing line and the step of acquiring a plurality of pieces of state data related to the states of a plurality of mechanisms constituting the manufacturing line in a computer. Acquiring the control program, identifying the connection state between the plurality of mechanisms by analyzing the acquired state data, and analyzing the acquired control program And a step of identifying a causal relationship between the plurality of mechanisms in a process performed on the production line based on the identified connection state and the order relationship, respectively. It is a program to make it.

  According to the present invention, a causal relationship between a plurality of mechanisms constituting a production line can be accurately modeled.

FIG. 1 schematically illustrates an example of an application scene of the process analysis apparatus according to the embodiment. FIG. 2 schematically illustrates an example of a hardware configuration of the process analysis apparatus according to the embodiment. FIG. 3 schematically illustrates an example of a hardware configuration of the control device (PLC) according to the embodiment. FIG. 4 schematically illustrates an example of the software configuration of the process analysis apparatus according to the embodiment. FIG. 5 illustrates an example of a processing procedure of the process analysis apparatus according to the embodiment. FIG. 6 illustrates an example of a processing procedure when analyzing the state data of the process analysis apparatus according to the embodiment. FIG. 7 illustrates an example of a process of analyzing state data. FIG. 8 illustrates the relationship between the control signal and the tact time. FIG. 9 illustrates an example of a processing procedure when analyzing a control program of the process analysis apparatus according to the embodiment. FIG. 10 illustrates an example of an abstract syntax tree constructed from a control program. FIG. 11A illustrates an example of a scene where the ordering of each variable is initialized. FIG. 11B illustrates an example of an order relationship between a plurality of mechanisms specified by analysis of the control program. FIG. 12 illustrates an example of directed graph information indicating a correlation between a plurality of mechanisms. FIG. 13A illustrates an operation example of the production line according to the embodiment. FIG. 13B shows an operation example of the production line according to the embodiment. FIG. 13C illustrates an operation example of the production line according to the embodiment. FIG. 14 shows a part of each feature amount obtained in the embodiment. FIG. 15 shows a correlation coefficient matrix calculated from each feature quantity of FIG. FIG. 16 shows undirected graph information obtained from the correlation coefficient matrix of FIG. FIG. 17 shows a part of the control program used in the embodiment. FIG. 18A shows an abstract syntax tree constructed from the control program of FIG. FIG. 18B shows an abstract syntax tree constructed from the control program of FIG. FIG. 18C shows an abstract syntax tree constructed from the control program of FIG. FIG. 18D shows an abstract syntax tree constructed from the control program of FIG. FIG. 19 shows the order relationship of each variable obtained in the example. FIG. 20 shows the directed graph information obtained in the example. FIG. 21 is a flowchart illustrating an example of a processing procedure for analyzing a control program. FIG. 22 schematically illustrates an example of a control flow graph. FIG. 23 is a flowchart illustrating an example of a processing procedure for specifying the dependency relationship between the variables based on the control flow graph. FIG. 24A schematically illustrates an example of the obtained variable group. FIG. 24B schematically illustrates the dependency relationship between the variables in the paired variable group. FIG. 24C schematically illustrates an example of an order relationship between a plurality of mechanisms specified based on a dependency relationship between variables. FIG. 25 schematically illustrates an example of the software configuration of the process analysis apparatus according to the modification. FIG. 26 illustrates an example of a process for analyzing mechanism data.

  Hereinafter, an embodiment according to an aspect of the present invention (hereinafter, also referred to as “this embodiment”) will be described with reference to the drawings. However, this embodiment described below is only an illustration of the present invention in all respects. It goes without saying that various improvements and modifications can be made without departing from the scope of the present invention. That is, in implementing the present invention, a specific configuration according to the embodiment may be adopted as appropriate. Although data appearing in this embodiment is described in a natural language, more specifically, it is specified by a pseudo language, a command, a parameter, a machine language, or the like that can be recognized by a computer.

§1 Application Example First, an example of a scene to which the present invention is applied will be described with reference to FIG. FIG. 1 schematically illustrates an example of a usage scene of the process analysis apparatus 1 according to the present embodiment.

  As shown in FIG. 1, the process analysis apparatus 1 according to the present embodiment acquires a plurality of pieces of state data 222 relating to the states of the plurality of mechanisms 31 that constitute the production line 3. The production line 3 only needs to be able to produce some product, and may be composed of a plurality of devices, or may be composed of one device such as a packaging machine. Moreover, each mechanism 31 should just be able to implement a certain process of a manufacturing process, may be comprised by 1 or several apparatus, and may be comprised by a part of apparatus. When one mechanism 31 is configured by a part of the apparatus, the plurality of mechanisms 31 may be configured by one apparatus. When the same apparatus performs a plurality of processes, each may be regarded as a separate mechanism 31. For example, when the same apparatus performs the first process and the second process, the apparatus that performs the first process is regarded as the first mechanism 31 and the apparatus that performs the second process is the second. The mechanism 31 may be considered. Further, the state data 222 may include any kind of data regarding the state of each mechanism 31 constituting the production line 3.

  Further, the process analysis apparatus 1 according to the present embodiment acquires a control program 221 for controlling the operation of the production line 3. The control program 221 may include any type of program that controls the operation of each mechanism 31 configuring the manufacturing line 3. The control program 221 may be composed of one program or a plurality of programs. In the present embodiment, the operation of the production line 3 is controlled by a PLC (programmable logic controller) 2. Therefore, the process analysis apparatus 1 acquires a plurality of state data 222 and a control program 221 from the PLC 2.

  Next, the process analysis apparatus 1 according to the present embodiment identifies the strength of the relationship between the plurality of mechanisms 31 in the manufacturing line 3 by statistically analyzing the plurality of acquired state data 222. The strength of the relationship is an example of the “connection state” in the present invention. Further, the process analysis apparatus 1 according to the present embodiment identifies the order relationship of the plurality of mechanisms 31 in the production line 3 by analyzing the acquired control program 221. And the process analysis apparatus 1 which concerns on this embodiment specifies the causal relationship between the some mechanisms 31 in the process performed in the manufacturing line 3 based on the strength and order relationship of the specified relationship, respectively.

  As described above, in the present embodiment, the control program 221 is used to identify the order relationship between the plurality of mechanisms 31 in the process of analyzing the causal relationship between the plurality of mechanisms 31. Since the control program 221 defines the operation of each mechanism 31, the order relationship of each mechanism 31 can be specified more accurately by using the control program 221. Therefore, according to this embodiment, the causal relationship between the plurality of mechanisms 31 constituting the production line 3 can be accurately modeled.

§2 Configuration example [Hardware]
<Process analysis equipment>
Next, an example of the hardware configuration of the process analysis apparatus 1 according to the present embodiment will be described with reference to FIG. FIG. 2 schematically illustrates an example of a hardware configuration of the process analysis apparatus 1 according to the present embodiment.

  As shown in FIG. 2, the process analysis apparatus 1 according to the present embodiment is a computer in which a control unit 11, a storage unit 12, a communication interface 13, an input device 14, an output device 15, and a drive 16 are electrically connected. is there. In FIG. 2, the communication interface is described as “communication I / F”.

  The control unit 11 includes a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), and the like, which are hardware processors, and controls each component according to information processing. The storage unit 12 is, for example, an auxiliary storage device such as a hard disk drive or a solid state drive, and stores a process analysis program 121 or the like executed by the control unit 11.

  The process analysis program 121 uses a plurality of state data 222 and the control program 221 to perform a later-described process (FIG. 5) for analyzing the causal relationship between the mechanisms 31 in the manufacturing process performed by the manufacturing line 3. It is a program for causing the analysis apparatus 1 to execute. Details will be described later.

  The communication interface 13 is, for example, a wired LAN (Local Area Network) module, a wireless LAN module, or the like, and is an interface for performing wired or wireless communication via a network. The process analysis apparatus 1 can perform data communication with the PLC 2 via the network by the communication interface 13. Note that the type of network may be appropriately selected from, for example, the Internet, a wireless communication network, a mobile communication network, a telephone network, and a dedicated network.

  The input device 14 is a device for performing input using, for example, a mouse or a keyboard. The output device 15 is a device for outputting, for example, a display or a speaker. An operator can operate the process analysis apparatus 1 via the input device 14 and the output device 15.

  The drive 16 is, for example, a CD drive, a DVD drive, or the like, and is a drive device for reading a program stored in the storage medium 91. The type of the drive 16 may be appropriately selected according to the type of the storage medium 91. The process analysis program 121 may be stored in the storage medium 91.

  The storage medium 91 stores information such as a program by an electrical, magnetic, optical, mechanical, or chemical action so that the information such as a program recorded by a computer or other device or machine can be read. It is a medium to do. The process analysis apparatus 1 may acquire the process analysis program 121 from the storage medium 91.

  Here, in FIG. 2, as an example of the storage medium 91, a disk-type storage medium such as a CD or a DVD is illustrated. However, the type of the storage medium 91 is not limited to the disk type and may be other than the disk type. Examples of the storage medium other than the disk type include a semiconductor memory such as a flash memory.

  It should be noted that regarding the specific hardware configuration of the process analysis apparatus 1, components can be omitted, replaced, and added as appropriate according to the embodiment. For example, the control unit 11 may include a plurality of processors. The process analysis apparatus 1 may be composed of a plurality of information processing apparatuses. Further, the process analysis device 1 may be a general-purpose server device, a PC (Personal Computer), or the like, in addition to an information processing device designed exclusively for the provided service.

<PLC>
Next, an example of the hardware configuration of the PLC 2 that controls the operation of the production line 3 will be described with reference to FIG. FIG. 3 schematically illustrates an example of the hardware configuration of the PLC 2 according to the present embodiment.

  As shown in FIG. 3, the PLC 2 is a computer in which a control unit 21, a storage unit 22, an input / output interface 23, and a communication interface 24 are electrically connected. Thereby, PLC2 is comprised so that operation | movement of each mechanism 31 of the manufacturing line 3 may be controlled. In FIG. 3, the input / output interface and the communication interface are described as “input / output I / F” and “communication I / F”, respectively.

  The control unit 21 includes a CPU, a RAM, a ROM, and the like, and is configured to execute various types of information processing based on programs and data. The storage unit 22 includes, for example, a RAM, a ROM, and the like, and stores a control program 221, status data 222, log data 223, and the like. The control program 221 is a program for controlling the operation of the production line 3. The state data 222 is data relating to the state of each mechanism 31. The log data 223 is data indicating an operation log of the production line 3.

  The input / output interface 23 is an interface for connecting to an external device, and is appropriately configured according to the external device to be connected. In the present embodiment, the PLC 2 is connected to the production line 3 via the input / output interface 23. When different state data can be acquired for a single device, the target single device may be regarded as a plurality of mechanisms 31 or a single mechanism 31. Therefore, the number of input / output interfaces 23 may be the same as the number of mechanisms 31 constituting the production line 3 or may be different from the number of mechanisms 31 constituting the production line 3.

  The communication interface 24 is, for example, a wired LAN module, a wireless LAN module, or the like, and is an interface for performing wired or wireless communication. The PLC 2 can perform data communication with the process analysis apparatus 1 through the communication interface 24.

  Note that regarding the specific hardware configuration of the PLC 2, the components can be omitted, replaced, and added as appropriate according to the embodiment. For example, the control unit 21 may include a plurality of processors. The storage unit 22 may be configured by a RAM and a ROM included in the control unit 21. The storage unit 22 may be configured by an auxiliary storage device such as a hard disk drive or a solid state drive. The PLC 2 may be replaced with a general-purpose desktop PC, tablet PC, or the like in accordance with an object to be controlled, in addition to an information processing apparatus designed exclusively for the provided service.

Software configuration
Next, an example of the software configuration of the process analysis apparatus 1 according to the present embodiment will be described with reference to FIG. FIG. 4 schematically illustrates an example of the software configuration of the process analysis apparatus 1 according to the present embodiment.

  The control unit 11 of the process analysis apparatus 1 expands the process analysis program 121 stored in the storage unit 12 in the RAM. The control unit 11 interprets and executes the process analysis program 121 expanded in the RAM by the CPU, and controls each component. Accordingly, as illustrated in FIG. 4, the process analysis apparatus 1 according to the present embodiment includes, as software modules, a first acquisition unit 111, a second acquisition unit 112, a first analysis unit 113, a second analysis unit 114, and A computer including the relationship specifying unit 115 is configured.

  The first acquisition unit 111 acquires a plurality of pieces of state data 222 relating to the states of the plurality of mechanisms 31 configuring the production line 3. The second acquisition unit 112 acquires a control program 221 for controlling the operation of the production line 3. The first analysis unit 113 identifies the strength of the relationship between the plurality of mechanisms 31 by statistically analyzing the acquired plurality of state data 222. The second analysis unit 114 identifies the order relationship of the plurality of mechanisms 31 by analyzing the acquired control program 221. In the present embodiment, the second analysis unit 114 specifies the order relationship between the mechanisms 31 using the log data 223 obtained by executing the control program 221. And the relationship specific | specification part 115 pinpoints the causal relationship between the some mechanisms 31 in the process implemented by the manufacturing line 3 based on the strength and order relationship of each specified relationship.

  Each software module of the process analysis apparatus 1 will be described in detail in an operation example described later. In the present embodiment, an example is described in which each software module of the process analysis apparatus 1 is realized by a general-purpose CPU. However, some or all of the above software modules may be realized by one or a plurality of dedicated hardware processors. In addition, regarding the software configuration of the process analysis apparatus 1, software modules may be omitted, replaced, and added as appropriate according to the embodiment.

§3 Operation Example Next, an operation example of the process analysis apparatus 1 will be described with reference to FIG. FIG. 5 illustrates an example of a processing procedure of the process analysis apparatus 1. The processing procedure of the process analysis apparatus 1 described below corresponds to the “process analysis method” of the present invention. However, the processing procedure described below is only an example, and each processing may be changed as much as possible. Further, in the processing procedure described below, steps can be omitted, replaced, and added as appropriate according to the embodiment.

[Step S101]
First, in step S <b> 101, the control unit 11 operates as the first acquisition unit 111 and acquires a plurality of state data 222 regarding the state of each mechanism 31 from the PLC 2. Each mechanism 31 may be configured by a device such as a conveyor, a robot arm, a servo motor, a cylinder (such as a molding machine), a suction pad, a cutter device, a seal device, or a part of the device. Further, each mechanism 31 may be, for example, a composite apparatus such as a printing machine, a mounting machine, a reflow furnace, and a board inspection apparatus. Furthermore, each mechanism 31 is not only a device with some physical operation as described above, for example, a device that detects some information by various sensors, a device that acquires data from various sensors, and some information from the acquired data. A device that performs internal processing, such as a device that detects data and a device that processes acquired data, may be included. As a specific example, in a production line including an optical sensor that detects a mark given to an object flowing on a conveyor, the optical sensor and a device that uses information detected by the optical sensor may be handled as each mechanism 31. Further, the status data 222 of each case includes, for example, at least one of torque, speed, acceleration, temperature, current, voltage, air pressure, pressure, flow rate, position, dimension (height, length, width) and area. It may be the data shown. Such state data 222 can be obtained by a known measuring device such as a sensor or a camera. For example, the flow rate can be obtained by a float sensor. Further, the position, size, and area can be obtained by an image sensor.

  The state data 222 may be composed of data obtained from one or a plurality of measuring devices. Further, the state data 222 may be the data obtained from the measuring device as it is, or can be obtained by applying some processing to the data obtained from the measuring device such as position data obtained from the image data. May be correct data. The status data 222 for each case is acquired corresponding to each mechanism 31.

  Each measuring device is appropriately arranged so that each mechanism 31 of the production line 3 can be monitored. The PLC 2 operates the production line 3 and collects the status data 222 for each case from each measuring device. The control unit 11 acquires state data 222 relating to the state of each mechanism 31 when the production line 3 is normally operated from the PLC 2. Thereby, the control unit 11 can acquire a plurality of pieces of state data 222. When the acquisition of the plurality of state data 222 is completed, the control unit 11 advances the processing to the next step S102.

[Step S102]
In the next step S102, the control unit 11 operates as the second acquisition unit 112, and acquires the control program 221 from the PLC 2. The control program 221 can be executed by the PLC 2, for example, at least one of a ladder diagram language, a function block diagram language, a structured text language, an instruction list language, a sequential function chart language, and a C language. It may be described using this. When the acquisition of the control program 221 is completed, the control unit 11 advances the processing to the next step S103. In addition, this step S102 may be performed in parallel with the said step S101, and may be performed before the said step S101.

[Step S103]
In the next step S103, the control unit 11 operates as the first analysis unit 113, and statistically analyzes the plurality of state data 222 acquired in step S101, whereby a plurality of mechanisms 31 in the production line 3 are Identify the strength of the relationship. When the analysis processing of the plurality of status data 222 is completed, the control unit 11 advances the processing to the next step S104. Note that this step S103 may be executed at any timing as long as it is after step S101. For example, step S103 may be executed before step S102.

<State data analysis processing>
Here, the processing for statistically analyzing a plurality of state data 222 will be described in detail with further reference to FIGS. 6 and 7. FIG. 6 illustrates an example of a processing procedure for analyzing the state data 222. FIG. 7 schematically illustrates an example of a process of analyzing the state data 222 according to the procedure shown in FIG. In the following description, for convenience of explanation, the production line 3 includes four mechanisms (for example, four servo motors) F1 to F4 as the plurality of mechanisms 31, and in step S101, the control unit 11 It is assumed that the state data 222 of each mechanism F1 to F4 has been acquired.

(Step S1301)
First, in step S1301, the control unit 11 calculates a feature amount 2221 from the state data 222 of each case acquired in step S101. The type of the feature amount 2221 is not particularly limited, and may be appropriately selected according to the embodiment. In addition, a method for calculating the feature amount 2221 can be appropriately determined according to the embodiment.

  As a specific example, in the present embodiment, the control unit 11 calculates the feature value 2221 from the state data 222 by the following method. First, the control unit 11 divides the acquired status data 222 for each frame in order to define a processing range for calculating the feature value 2221. The length of each frame may be appropriately set according to the embodiment.

  For example, the control unit 11 may divide the status data 222 of each case into frames each having a certain length of time. However, the production line 3 does not necessarily operate at regular time intervals. Therefore, if the status data 222 for each case is divided into frames of a certain time length, the operation of each mechanism 31 reflected in each frame may be shifted.

  Therefore, the control unit 11 may divide the state data 222 into frames for each tact time. The tact time is the time required for the production line 3 to produce a predetermined number of products. This tact time can be specified based on a signal for controlling the production line 3, for example, a control signal for controlling the operation of each mechanism 31 of the production line 3 by the PLC 2.

  The relationship between the control signal and the tact time will be described with reference to FIG. FIG. 8 schematically illustrates the relationship between the control signal and the tact time. As shown in FIG. 8, the control signal for the production line 3 that repeats production of products is a pulse signal in which “on” and “off” appear periodically according to the production of a predetermined number of products.

  For this reason, the control unit 11 can acquire this control signal from the PLC 2 and set the time from the rising edge (“on”) of the acquired control signal to the next rising edge (“on”) as the tact time. And the control part 11 can divide | segment the status data 222 into a flame | frame for every tact time so that it may be illustrated by FIG.

  Next, the control unit 11 calculates the value of the feature amount 2221 from each frame of the state data 222. When the state data 222 is continuous value data such as measurement data, the control unit 11 may, for example, determine the amplitude, maximum value, minimum value, average value, variance value, standard deviation, instantaneous value (1) within the frame. Point sample) may be calculated as the feature amount 2221. Further, when the state data 222 is discrete value data such as detection data, the control unit 11, for example, “on” time, “off” time, duty ratio, “on” number of times in each frame, The “off” number of times may be calculated as the feature amount 2221. Thus, when the calculation of each feature amount 2221 is completed, the control unit 11 advances the processing to the next step S1302.

(Step S1302)
Returning to FIGS. 6 and 7, in the next step S <b> 1302, the control unit 11 calculates a correlation coefficient or a partial correlation coefficient between the feature amounts 2221. The correlation coefficient can be calculated by the following equation (1). The partial correlation coefficient can be calculated by the following equation (2).

Note that r _ij represents an element in the i-th row and j-th column of the matrix 2222. x _i and x _j correspond to data indicating the feature value 2221 calculated from the state data 222 of each case. X _i and X _j denote sample averages of x _i and x _j , respectively. n indicates the number of feature quantities 2221 used for correlation calculation.

Incidentally, the inverse matrix of the matrix R (r _ij) is expressed as ^{R -1 (r ij), r} ij denotes the i-th row j-th column element of the inverse matrix of the matrix 2222.

  Thereby, the control part 11 can obtain the matrix 2222 which has a correlation coefficient or a partial correlation coefficient as each element. The correlation coefficient and partial correlation coefficient between the feature quantities 2221 indicate the strength of the relationship between the corresponding mechanisms 31. That is, the strength of the relationship between the corresponding mechanisms 31 is specified by each element of the matrix 2222. When the calculation of the correlation coefficient or the partial correlation coefficient between the feature amounts 2221 is completed, the control unit 11 advances the processing to the next step S1303.

(Step S1303)
In the next step S1303, the control unit 11 constructs undirected graph information 2223 indicating the strength of the relationship between the corresponding mechanisms 31 based on the correlation coefficient or partial correlation coefficient between the feature amounts 2221.

  For example, the control unit 11 creates a node corresponding to each mechanism 31. And when the value of the correlation coefficient or partial correlation coefficient calculated with respect to between the two mechanisms 31 is more than a threshold value, the control part 11 connects between both corresponding nodes with an edge. On the other hand, when the value of the correlation coefficient or partial correlation coefficient calculated for the two mechanisms 31 is less than the threshold value, the control unit 11 does not connect the corresponding nodes with an edge. The threshold value may be a fixed value defined in the process analysis program 121 or may be a setting value that can be changed by an operator or the like. Further, the thickness of the edge may be determined corresponding to the magnitude of the value of the corresponding correlation coefficient or partial correlation coefficient.

  Thereby, the undirected graph information 2223 illustrated in FIG. 7 can be created. In the example of FIG. 7, four nodes corresponding to the four mechanisms F1 to F4 are created. Edges are formed between the nodes of the mechanisms F1 and F2, between the nodes of the mechanisms F1 and F3, between the nodes of the mechanisms F2 and F3, and between the nodes of the mechanisms F3 and F4. Also, edges between mechanisms F1 and F3 and between nodes of mechanisms F3 and F4 correspond to the fact that the correlation between mechanisms F1 and F3 and between mechanisms F3 and F4 is greater than the correlation between other mechanisms. Is formed thicker than other edges. As described above, when the construction of the undirected graph information 2223 indicating the strength of the relationship between the plurality of mechanisms 31 is completed, the analysis processing of the state data 222 according to the present embodiment is completed, and the control unit 11 performs the next step S104. Proceed with the process.

  In the example of FIG. 7, the undirected graph information 2223 represents the formed undirected graph with an image. However, the output format of the undirected graph information 2223 is not limited to an image, and may be expressed by text or the like. In the above example, an edge is not formed between nodes (mechanism 31) having a weak relationship by comparing the correlation coefficient or the partial correlation coefficient with a threshold value. However, the method for removing edges between weakly related nodes is not limited to such an example. For example, after forming a graph in which all the nodes are connected by edges, the control unit 11 causes the correlation coefficient or partial correlation coefficient so that the fitness index (GFI, SRMR, etc.) indicating the deviation does not exceed the threshold value. The edges of the formed graph may be deleted in order from the smallest edge.

[Step S104]
Returning to FIG. 5, in the next step S <b> 104, the control unit 11 operates as the second analysis unit 114, and analyzes the control program 221 acquired in step S <b> 102, whereby the order of the mechanisms 31 in the production line 3. Identify relationships. In the present embodiment, the control unit 11 specifies the order relationship of the plurality of mechanisms 31 based on the log data 223 obtained by operating the production line 3 using the control program 221. When the analysis process of the control program 221 is completed, the control unit 11 advances the process to the next step S105. Note that this step S104 may be executed at any timing as long as it is after step S102. For example, when step S102 is executed before step S101, step S104 may be executed before step S101.

<Control program analysis processing>
Here, the process of analyzing the control program 221 will be described in detail with further reference to FIG. FIG. 9 illustrates an example of a processing procedure for analyzing the control program 221. In the following description, for convenience of explanation, the manufacturing line 3 includes four mechanisms F1 to F4 as the plurality of mechanisms 31 as described above. In step S102, the control unit 11 includes four mechanisms F1 to F4. It is assumed that the control program 221 using the variables v1 to v4 corresponding to the mechanisms F1 to F4 is acquired.

(Step S1401)
First, in step S1401, the control unit 11 performs syntax analysis of the acquired control program 221 and constructs an abstract syntax tree from the control program 221. For the construction of the abstract syntax tree, a known parsing method by top-down parsing or bottom-up parsing may be used. For example, a syntax analyzer that handles a character string according to a specific formal grammar may be used to construct an abstract syntax tree. When the construction of the abstract syntax tree is completed, the control unit 11 advances the processing to the next step S1402.

  FIG. 10 illustrates an abstract syntax tree 2211 obtained from the syntax “if (a> 0) [v1 = a;] else [v2 = −a;]” in the control program 221. As illustrated in FIG. 10, the abstract syntax tree is a data structure in which the structure of the program is expressed by a tree structure in order to interpret the meaning of the program.

  Specifically, the control unit 11 omits tokens such as parentheses that are not necessary for interpretation of the meaning of the program among tokens (lexical terms) used in the program, and relates to the interpretation of the meaning of the program. To extract. Then, the control unit 11 associates an operator such as a conditional branch with a node and associates an operand such as a variable with a leaf. The control unit 11 can construct an abstract syntax tree illustrated in FIG. 10 by performing syntax analysis of the control program 221 in this way. Note that the abstract syntax tree configured in this way represents the relationship between variables, operators, and nodes (such as the relationship between operations and operands). Regarding the configuration of the abstract syntax tree, the notation may be modified, changed, omitted, or the like as appropriate as long as the content shown does not change.

(Step S1402)
In the next step S1402, the control unit 11 extracts variables (v1 to v4) related to each mechanism 31 and operators including conditional branches and assignment operations from the abstract syntax tree constructed in step S1401. For example, when the abstract syntax tree 2211 shown in FIG. 10 is obtained, the control unit 11 (“if”, “v1”, “=”, “a”, “v2”, “=” from the abstract syntax tree 2211 concerned. And “-a”). When the extraction is completed, the control unit 11 advances the processing to the next step S1403.

(Step S1403 and Step S1404)
In the next step S1403, the control unit 11 arranges the variables and operators extracted in step S1402 in order, and sets the parts related to the variables (v1 to v4) corresponding to the mechanisms 31 that are the targets for specifying the causal relationship. Limit the targets for monitoring the execution order. In the above example, the control unit 11 (“if”, “v1”, “=”, “a”, “v2”, “=”, and “−a”) to (“if”, “v1”) , And “v2”).

  In the next step S1404, conditional branching is randomly selected and the control program 221 is tried to execute, thereby initializing the ordering of the limited variables. Specifically, the control unit 11 can initialize the ordering of each variable by monitoring the order in which each limited variable is used in an attempt to execute the control program 221.

FIG. 11A illustrates an example of the initialization. A graph 2212 in FIG. 11A shows the following order relationships (1) to (5) as a result of initialization.
(1) Among the variables “v1” to “v4”, the variable “v1” is used first.
(2) Next to the variable “v1”, the variable “v2” is used with a probability of 0.5, and the variable “v3” is used with a probability of 0.5.
(3) Next to the variable “v2”, the variable “v3” is used with a probability of 1.
(4) After the variable “v3”, the variable “v4” is used with a probability of 1.
(5) Among the variables “v1” to “v4”, the variable “v4” is used last.
When such initialization is completed, the control unit 11 advances the processing to the next step S1405.

(Step S1405)
In the next step S 1405, the control unit 11 acquires log data 223 indicating the execution result when the production line 3 is normally operated using the control program 221 from the PLC 2. For example, when collecting the state data 222, the PLC 2 may also create log data 223 indicating the execution result of the control program 221. In this case, the log data 223 records a time stamp, a value of a used variable, and the like. Further, for example, the control program 221 may be provided with a debug mode for collecting information such as the frequency with which each code line is executed, the executed code line, and the calculation time consumed by each section of code. . In this case, the PLC 2 can create log data 223 in which each information is recorded by executing the control program 221 in the debug mode. The control unit 11 may acquire the log data 223 created in this way from the PLC 2. When the acquisition of the log data 223 is completed, the control unit 11 advances the processing to the next step S1406.

(Step S1406)
In the next step S1406, the control unit 11 refers to the log data 223 acquired in step S1405, and performs ordering of the variables (v1 to v4) based on the execution result of the conditional branch. The order relation of the mechanisms 31 in the line 3 is specified.

FIG. 11B illustrates an example of the ordering result. A graph 2213 in FIG. 11B shows the following order relationships (A) to (E) as a result of ordering using the log data 223.
(A) Of the variables “v1” to “v4”, the variable “v1” is used first.
(B) Next to the variable “v1”, the variable “v2” is used with a probability of 0.01, and the variable “v3” is used with a probability of 0.99.
(C) Next to the variable “v2”, the variable “v3” is used with a probability of 1.
(D) After the variable “v3”, the variable “v4” is used with a probability of 1.
(E) Among the variables “v1” to “v4”, the variable “v4” is used last.
As described above, when the identification of the order relation of the plurality of mechanisms 31 is completed, the analysis process of the control program 221 according to the present embodiment is completed, and the control unit 11 advances the process to the next step S105.

[Step S105]
Returning to FIG. 5, in the next step S <b> 105, the control unit 11 operates as the relationship specifying unit 115. That is, the control unit 11 determines the plurality of mechanisms in the process performed in the manufacturing line 3 based on the strength and order relationship of the relationships between the plurality of mechanisms 31 in the manufacturing line 3 specified in steps S103 and S104. The causal relationship between 31 is specified.

  In the present embodiment, the control unit 11 applies the order relationship of the mechanisms 31 identified in step S1406 to the undirected graph information 2223 constructed in step S1303, thereby indicating a directed graph indicating the causal relationship between the mechanisms 31. Create information. At this time, the control unit 11 identifies an order (transition) in which the probability of occurrence in the order relationship of each mechanism 31 is lower than the threshold, and deletes an edge corresponding to the identified order from the edges constituting the undirected graph information 2223 May be. The threshold value may be a fixed value defined in the process analysis program 121 or may be a setting value that can be changed by an operator or the like.

FIG. 12 illustrates an example of the generated directed graph information. A directed graph 122 in FIG. 12 shows the following causal relationships (a) to (d).
(A) Of the mechanisms “F1” to “F4”, the mechanism “F1” or “F2” is used first.
(B) The mechanism “F3” is used next to the mechanisms “F1” and “F2”.
(C) The mechanism “F4” is used next to the mechanism “F3”.
(D) Among the mechanisms “F1” to “F4”, the mechanism “F4” is used last.
In the example of FIG. 12, the edge between the mechanisms “F1” and “F2” that existed in the undirected graph information 2223 corresponds to the low occurrence probability of the order from the variable “v1” to “v2”. It has been deleted. Further, the thickness of each edge of the directed graph 122 is set corresponding to the thickness of each edge of the undirected graph information 2223. As described above, when the creation of the directed graph information is completed, the control unit 11 advances the processing to the next step S106.

  In the example of FIG. 12, the directed graph information represents a directed graph (directed graph 122) with an image. However, the output format of the directed graph information need not be limited to images, and may be expressed by text or the like. In the above example, the strength of the relationship between the nodes (mechanisms 31) is expressed by the thickness of the edge. However, the method of expressing the strength of the relationship between the nodes may not be limited to such an example. You may express the strength of the relationship between each node by attaching | subjecting a number to the vicinity of each edge.

[Step S106]
In the next step S106, the control unit 11 outputs the directed graph information created in step S105. For example, the control unit 11 outputs the directed graph created in the output device 15 such as a display in an image format. As described above, the control unit 11 ends the process according to this operation example.

[Feature]
As described above, in this embodiment, the order relationship between the plurality of mechanisms 31 in the production line 3 is specified by analyzing the control program 221 in step S104. Then, by applying the order relation specified from the control program 221 to the undirected graph information indicating the strength of the relation derived from the state data 222 in the above step S103, a plurality of mechanisms in the process performed in the production line 3 is performed. Directed graph information indicating the causal relationship between 31 is created. Here, the control program 221 defines the operation of each mechanism 31. Therefore, in the process of analyzing the causal relationship between the plurality of mechanisms 31, the order relationship between the plurality of mechanisms 31 can be appropriately specified by using the control program 221. Therefore, according to this embodiment, the causal relationship between the plurality of mechanisms 31 constituting the production line 3 can be accurately modeled.

  In this embodiment, the directed graph information illustrated in FIG. 12 (and FIG. 20 described later) is output as a result of analyzing the causal relationship between a plurality of mechanisms constituting the production line in step S106. The output directed graph information simply indicates the causal relationship between the mechanisms. Therefore, according to this embodiment, even the unskilled maintenance staff can easily understand the causal relationship between a plurality of mechanisms constituting the production line by the output directed graph information.

[Example]
Next, an embodiment of a process of creating directed graph information indicating the causal relationship between the mechanisms 31 by the processing of steps S101 to S106 will be described. However, the present invention is not limited to the following examples.

As an example, directed graph information indicating a causal relationship between each mechanism of a production line having the following conditions was created.
<Various conditions>
・ Production line: Manufacturing equipment / mechanisms (six) that fix two parts on the mounting position on the board:
-A first mechanism for adjusting the X-axis position of the substrate (marker)-A second mechanism for adjusting the Y-axis position of the substrate (marker)-A third mechanism for adjusting the A-axis position of the first component-First Fourth mechanism for adjusting the position of the B-axis of the part-Fifth mechanism for adjusting the position of the C-axis of the second part-Program language of the sixth mechanism / control program for adjusting the position of the D-axis of the second part: ST Language / Measurement device: Camera / Status data: Position / feature of each axis adjusted by each mechanism: Instantaneous value / Process analysis device: General-purpose PC
For convenience of explanation, the first to sixth mechanisms are respectively referred to as “marker position X axis”, “marker position Y axis”, “first part position A axis”, “first part position B axis”, “ Also referred to as “second component position C-axis” and “second component position D-axis”. “X axis”, “A axis”, and “C axis” correspond to the vertical axis of the image obtained by the camera, and “Y axis”, “B axis”, and “D axis” correspond to the horizontal axis of the image. Correspond.

  Here, the manufacturing apparatus which comprises the manufacturing line based on an Example is demonstrated using FIG. 13A-FIG. 13C. 13A to 13C schematically illustrate the configuration of the manufacturing apparatus. As illustrated in FIGS. 13A to 13C, the manufacturing apparatus according to the embodiment includes a conveyor 51 that transports the substrate 52, a first robot arm 531 that transports the first component 53, and a second that transports the second component 54. A robot arm 541 and a camera 55 for photographing a work place are provided. The position of the substrate 52 on the conveyor 51 is adjusted by the first mechanism and the second mechanism, the position of the first component 53 held by the first robot arm 531 is adjusted by the third mechanism and the fourth mechanism, and the fifth mechanism and The position of the second component 54 held by the second robot arm 541 is adjusted by the sixth mechanism.

  The manufacturing apparatus conveys the substrate 52 to a predetermined position by the conveyor 51 (FIG. 13A). A marker 521 is provided on the surface of the substrate 52, and positioning is performed by the marker 521. Next, the manufacturing apparatus fixes the first component 53 to the first mounting position 522 provided on the surface of the substrate 52 by the first robot arm 531 (FIG. 13B). Then, the manufacturing apparatus fixes the second component 54 to the second mounting position 523 provided on the surface of the substrate 52 by the second robot arm 541 (FIG. 13C). Thus, a product in which two components (53, 54) are mounted on the upper surface of the substrate 52 can be manufactured.

  In this example, in order to perform the state data analysis process, 1000 products were manufactured intermittently, and the process was photographed by the camera 55. The manufacturing time per product was about 1 minute. In the obtained image data 551, the X-axis and Y-axis of the substrate 52 (marker 521), the A-axis and B-axis of the first component 53, the C-axis of the second component, and the D-axis position (coordinates). ) Was specified, and feature quantities corresponding to each mechanism were obtained. FIG. 14 shows a part of each feature amount obtained as described above.

  Subsequently, by applying each feature quantity shown in FIG. 14 to the mathematical formula shown in Equation 1, a correlation coefficient matrix indicating a correlation between each feature quantity was calculated. FIG. 15 shows the calculated correlation coefficient matrix. Undirected graph information indicating the strength of the relationship between the mechanisms was obtained by extracting elements having a correlation coefficient value of 0.2 or more from each element of the correlation coefficient matrix. FIG. 16 shows the undirected graph information obtained as a result.

  In addition, a control program used by the manufacturing apparatus was obtained in order to perform control program analysis processing. FIG. 17 shows a part of the control program thus obtained. Next, an abstract syntax tree was constructed by performing syntax analysis of the control program using known software (name: Sysmac (registered trademark) Studio). 18A to 18D show a part of the abstract syntax tree thus constructed. Each abstract syntax tree shown in FIGS. 18A to 18D corresponds to each syntax of reference numerals 561 to 564 in FIG. The processing of steps S1402 to S1404 was applied to this abstract syntax tree to initialize the ordering of each variable corresponding to each mechanism. Furthermore, the order relation of each mechanism when operating normally was specified by using the log data obtained in the above manufacturing process. FIG. 19 shows the order relationship of the mechanisms specified by this. In addition, the number attached | subjected to the edge of FIG. 19 shows the probability that the transition between nodes will generate | occur | produce, and the direction of the arrow shows the direction of the transition which generate | occur | produces.

  Then, by applying the order relationship (FIG. 19) specified by the control program analysis to the undirected graph information (FIG. 16) obtained by the state data analysis, the directed graph information indicating the causal relationship of each mechanism is obtained. It was. When forming the directed graph information, an edge corresponding to a transition having a probability of occurring in the order relation shown in FIG. FIG. 20 shows the directed graph information obtained as a result. The directed graph information in FIG. 20 indicates a causal relationship that the manufacturing apparatus operates in the order of “movement of the substrate (marker)”, “mounting of the first component”, and “mounting of the second component” in each axis. . This causal relationship is consistent with the actual operation of the manufacturing apparatus. Therefore, according to the method according to the above embodiment, it has been found that the causal relationship between a plurality of mechanisms constituting the production line can be accurately modeled.

§4 Modifications Embodiments of the present invention have been described in detail above, but the above description is merely an illustration of the present invention in all respects. It goes without saying that various improvements and modifications can be made without departing from the scope of the present invention. For example, the following changes are possible. In the following, the same reference numerals are used for the same components as in the above embodiment, and the description of the same points as in the above embodiment is omitted as appropriate. The following modifications can be combined as appropriate.

<4.1>
In the above-described embodiment, the process analysis device 1 acquires the control program 221 from the PLC 2 that is a control device that controls the production line 3. However, the acquisition destination of the control program to be analyzed does not have to be limited to the control device using the control program, and may be appropriately selected according to the embodiment. For example, when the control program is stored in an external storage device such as NAS (Network Attached Storage), the process analysis apparatus 1 may acquire the control program from the external storage device. For example, when the control program is stored in a storage medium such as a CD or a semiconductor memory, the process analysis apparatus 1 may acquire the control program from the storage medium. In particular, in the above embodiment, the control program is analyzed by constructing an abstract syntax tree. This abstract syntax tree can be created in the process of compiling a program written in a programming language. Therefore, it is preferable that the process analysis apparatus 1 acquires the pre-compiled program as the control program 221. When the control device does not hold the pre-compiled program, the process analysis device 1 can download the pre-compile program corresponding to the control program executed by the control device from an external device other than the control device, a storage medium, or the like. You may get it.

<4.2>
In the above embodiment, the control program 221 can be executed by the PLC 2, for example, a ladder diagram language, a function block diagram language, a structured text language, an instruction list language, and a sequential function chart language. It is described using at least one of C languages. However, the type of control program to be analyzed does not have to be limited to such an example, and may be appropriately selected according to the embodiment. For example, the control program to be analyzed may be described using Java (registered trademark), Python, C ++, Ruby, Lua, or the like.

<4.3>
In the above embodiment, the process analysis apparatus 1 acquires the state data 222 from the PLC 2 that controls the production line 3. However, the acquisition source of the state data to be analyzed does not have to be limited to the control device that controls the production line, and may be appropriately selected according to the embodiment. For example, when the state data is stored in an external storage device such as NAS, the process analysis device 1 may acquire the state data from the external storage device. For example, when the state data is stored in a storage medium such as a CD or a semiconductor memory, the process analysis apparatus 1 may acquire the state data from the storage medium. Further, for example, the process analysis device 1 may directly acquire the state data from each measurement device.

<4.4>
In the above embodiment, the process analysis apparatus 1 outputs the result of analyzing the causal relationship between the plurality of mechanisms 31 as directed graph information. However, the output format of the analysis result may not be limited to such an example, and may be appropriately selected according to the embodiment. The analysis result of the causal relationship may be expressed by, for example, a transition probability matrix, text, or the like.

  In the above embodiment, the directed graph information is created using the undirected graph information constructed in step S1303. However, the method of creating the directed graph information may not be limited to such an example. For example, the process analysis apparatus 1 may omit the step S1303 and create directed graph information using a matrix of correlation coefficients or partial correlation coefficients.

<4.5>
In the above embodiment, the process analysis apparatus 1 and the PLC 2 are configured by separate computers. However, the process analysis apparatus 1 and the PLC 2 may be configured by a single computer. That is, one computer may have the functions of both the process analysis device and the production line control device.

<4.6>
In the above-described embodiment, the process analysis apparatus 1 calculates the feature amount from the state data 222 of each case before calculating the correlation coefficient or the partial correlation coefficient in the process of analyzing the state data 222. However, the method of statistically analyzing the state data 222 may not be limited to such an example. For example, the process analysis apparatus 1 may calculate the correlation coefficient or the partial correlation coefficient using the state data 222 of each case as it is.

  Moreover, in the said embodiment, in order to show the strength of the relationship between each mechanism 31, a correlation coefficient or a partial correlation coefficient is used. However, the index indicating the strength of the relationship between the mechanisms does not have to be limited to the correlation coefficient or the partial correlation coefficient, and may be appropriately selected according to the embodiment. For example, MIC (Maximum Information Coefficient), HSIC (Hilbert-Schmidt Independence Criteria), mutual information, or the like may be used as an index indicating the strength of the relationship between the mechanisms.

<4.7>
In the above embodiment, the process analysis apparatus 1 analyzes the control program 221 using an abstract syntax tree. However, the method of analyzing the control program is not limited to such an example, and may be appropriately selected according to the embodiment. For example, the process analysis apparatus 1 may analyze the control program using an intermediate language code formed in the compilation process.

  Further, in the above embodiment, execution of conditional branching is performed by referring to log data 223 obtained by operating the production line 3 using the control program 221 after extracting variables and conditional branches from the abstract syntax tree. By ordering each variable based on the result, the order relation of the plurality of mechanisms 31 is specified. However, the method for specifying the order relationship of the plurality of mechanisms 31 based on the log data 223 may not be limited to such an example. The process analysis apparatus 1 may specify the order relationship of the plurality of mechanisms 31 by appropriately analyzing the log data 223.

<4.8>
In the above embodiment, the process analysis apparatus 1 specifies the strength of the relationship between the plurality of mechanisms 31 as the connection state between the plurality of mechanisms 31 in step S103. However, the representation method of the connection state may not be limited to such an example, and may be appropriately determined according to the embodiment. For example, the connection state between the plurality of mechanisms 31 may be expressed by the presence or absence of a relationship, a change in the relationship, or the like. The change in the relationship may be indicated by, for example, a difference (change amount) in the time series of the relationship expressed by the strength or presence of the relationship.

<4.9>
In the above embodiment, the process analysis apparatus 1 statistically analyzes the plurality of state data 222 by calculating the correlation coefficient or the partial correlation coefficient in step S103. However, the method of statistically analyzing a plurality of state data 222 may not be limited to such an example, and may be appropriately determined according to the embodiment. In step S103, the control unit 11 may statistically analyze a plurality of pieces of state data 222 by, for example, GLASSO (Graphical LASSO), a covariance selection method, or the like. Thereby, the control part 11 can obtain the undirected graph which shows the connection state between the some mechanisms 31. FIG. Further, in step S103, the control unit 11, for example, includes SGS (Spirtes, Glymour, and Scheines), PC (Peter & Clark), FCI (Fast Causal Inference), LiNGAM (Liner Non-Gaussian Acyclic Model), Bayesian network. For example, a plurality of status data 222 may be statistically analyzed. Thereby, the control part 11 can obtain the directed graph which shows the connection state between the some mechanisms 31. FIG.

<4.10>
In the above embodiment, the process analysis apparatus 1 statistically analyzes a plurality of state data 222 in step S103. However, the method of analyzing the plurality of state data 222 may not be limited to such a statistical method, and the control unit 11 uses a method other than the statistical method in step S103 to determine the plurality of state data. 222 may be analyzed.

  For example, the control unit 11 calculates a feature amount from each case state data 222 obtained from each mechanism 31, and specifies a connection state between the plurality of mechanisms 31 based on the calculated change in each feature amount. Also good. The type of feature amount to be calculated may be the same as that in step S1301. As an example of a method for specifying a connection state based on a change in each feature amount, when an abnormality such as a failure occurs between related mechanisms 31, the feature amount obtained from each related mechanism 31 greatly changes. Therefore, the control unit 11 may extract the feature amount that has changed more than the threshold value by comparing the calculated change amount of each feature amount with a predetermined threshold value. Then, the control unit 11 may specify the connection state on the assumption that there is a relationship between the mechanisms 31 corresponding to the extracted feature amount.

  Further, for example, the control unit 11 may analyze a plurality of pieces of state data 222 using a learning model obtained by machine learning such as a decision tree, logistics regression, Bayesian network, or neural network. As an example of a method using a learning model, the control unit 11 acquires a learned learning model that has been subjected to machine learning to acquire the ability to determine whether or not an abnormality has occurred based on state data. Also good. Then, the control unit 11 may input the state data 222 of each case into the acquired learning model, and acquire an output indicating whether or not an abnormality has occurred in the corresponding mechanism 31 from the learned learning model. Thereby, the control part 11 can pinpoint the connection state between the some mechanisms 31 by considering that the mechanisms 31 determined that abnormality has arisen.

<4.11>
In the said embodiment, the process analysis apparatus 1 specifies the order relationship between the some mechanisms 31 using the log data 223 in the said step S104. However, the method for specifying the order relationship between the plurality of mechanisms 31 is not limited to the method using the log data 223. The process analysis apparatus 1 may specify the order relationship between the mechanisms 31 without using the log data 223.

  FIG. 21 is a flowchart illustrating an example of a processing procedure for analyzing the control program 221 in the present modification. For example, the control unit 11 may operate as the second analysis unit 114 and specify the order relationship between the plurality of mechanisms 31 according to the processing procedure illustrated in FIG. 21 instead of step S104.

(Step S1411)
In step S1411, the control unit 11 constructs an abstract syntax tree from the control program 221 by performing syntax analysis of the acquired control program 221. The construction of the abstract syntax tree may be performed in the same manner as in step S1401. When the construction of the abstract syntax tree is completed, the control unit 11 advances the processing to the next step S1412.

(Step S1412)
In step S1412, the control unit 11 extracts a variable related to each mechanism 31 from the abstract syntax tree constructed in step S1411. The variable extraction may be performed in the same manner as in step S1402. When the extraction of the variables related to each mechanism 31 is completed, the control unit 11 advances the processing to the next step S1413.

(Step S1413)
In step S1413, the control unit 11 generates a control flow graph from the abstract syntax tree constructed in step S1411. The control flow graph is a graph showing all paths that may be taken when the program is executed.

  Here, the control flow graph will be described with reference to FIG. FIG. 22 schematically illustrates an example of a program (program 501) and an example of a control flow graph derived from the example of the program (control flow graph 502). In the example of FIG. 22, the program 501 includes processes L1 to L6. A control flow graph 502 shown in FIG. 22 can be obtained by performing dependency analysis of the program 501 using an abstract syntax tree constructed from the program 501.

  The control flow graph 502 shows the flow of processing of the program 501 (solid line arrow), data dependency (dotted line arrow), and control dependency (dotted line arrow). The process flow indicates the order in which the processes in the program are executed. For example, in the program 501, the process L2 is executed after the process L1. Therefore, in the control flow graph 502, the process L1 and the process L2 are connected by an arrow indicating the flow of the process. Further, the process L4 has a branch syntax, and based on the execution result of the process L4, the process to be executed next is determined as either the process L5 or the process L6. Therefore, the process L4 is connected to the process L5 and the process L6 by an arrow indicating a process flow.

  The dependency of data indicates the relationship of processing that affects the data. For example, in the program 501, the process L2 affects the results of the process L4 and the process L5. Therefore, in the control flow graph 502, the process L2 is connected to the process L4 and the process L5 by arrows indicating data dependency. Further, the control dependency indicates the relationship of processing for determining whether or not execution is possible by conditional branching or the like. For example, in the program 501, whether or not the process L5 can be executed is determined based on the execution result of the process L4. Therefore, in the control flow graph 502, the process L4 is connected to the process L5 by an arrow indicating control dependency.

  Thus, according to the control flow graph, it is possible to specify the dependency relationship between the processes including the calculation of the variables in the control program 221. The control unit 11 generates a control flow graph by performing dependency analysis of the control program 221 using an abstract syntax tree. Then, when the generation of the control flow graph is completed, the control unit 11 advances the processing to the next step S1414. This step S1413 may be executed before step S1412 or may be executed in parallel with step S1412.

(Steps S1414 and S1415)
In step S1414, the control unit 11 specifies the dependency relationship of the extracted variable based on the generated control flow graph. In this modification, the control unit 11 identifies the dependency relationship of variables in the processing of the control program 221 based on the abstract syntax tree constructed in step S1411 through the above step S1413 and step S1414. In the next step S1415, the control unit 11 specifies the order relationship of the plurality of mechanisms 31 based on the dependency relationship of the specified variable. When the identification of the order relationship of the plurality of mechanisms 31 is completed, the analysis process of the control program 221 according to the present modification ends.

  Here, the processing in steps S1414 and S1415 will be described with reference to FIG. FIG. 23 is a flowchart illustrating an example of a processing procedure for specifying the dependency relationship between the variables based on the control flow graph and specifying the order relationship of the plurality of mechanisms 31 based on the dependency relationship between the specified variables.

(Step S401)
In step S401, the control unit 11 generates a variable group corresponding to each mechanism 31 by grouping the variables extracted in step S1412.

  FIG. 24A schematically illustrates an example of a scene for generating a variable group. When the control program 221 is divided into a plurality of programs, the same name is not necessarily given to variables corresponding to the same mechanism 31. Therefore, the control unit 11 picks up the attention variable corresponding to each mechanism 31 from the variables obtained in step S1412. Subsequently, the control unit 11 extracts global variables depending on each target variable from the variables obtained in step S1412. Then, the control unit 11 generates a group of each attention variable and a global variable depending on each attention variable as a variable group corresponding to each mechanism 31. Thereby, the control unit 11 can perform grouping of variables corresponding to the respective mechanisms 31. When the variable grouping is completed, the control unit 11 advances the processing to the next step S402.

(Step S402)
In step S402, the control unit 11 selects two variable groups from the variable groups generated in step S401. Thereby, the control unit 11 generates a pair (combination) of variable groups and lists the generated pairs of variable groups. For example, assume that three variable groups D (A), D (B), and D (C) are generated. In this case, the control unit 11 performs (D (A), D (B)), (D (A), D (C)), (D (B), D (C)) by the process of step S402. You can list three variable group pairs. When the list of variable group pairs is completed, the control unit 11 advances the processing to the next step S403.

(Step S403)
In step S403, the control unit 11 extracts one variable group pair from the variable group pairs listed in step S402, and extracts one variable from each variable group of the extracted pair. As a result, the control unit 11 generates variable pairs included in each variable group, and lists the generated variable pairs. For example, a pair of (D (A), D (B)) is taken out, and the variable group D (A) includes two variables AA1 and AA2, and the variable group D (B) includes BB1. , BB2 are included. In this case, the control unit 11 can list the four variable pairs (AA1, BB1), (AA1, BB2), (AA2, BB1), (AA2, BB2) by the process of step S403. it can. When the list of variable pairs is completed, the control unit 11 advances the processing to the next step S404.

(Step S404)
In step S404, the control unit 11 extracts one variable pair from the variable pairs listed in step S403, and derives a dependency relationship between the extracted pair variables based on the control flow graph. For example, assume that a pair (AA1, BB1) is taken out. When the control flow graph shows a dependency relationship that the process including BB1 is executed after the process including AA1, the control unit 11 determines that AA1 is first and BB1 is later in this step S404. It can be derived that there is an order dependency. Similarly, when the control flow graph shows a dependency relationship that a process including AA1 is executed after a process including BB1, the control unit 11 determines that AA1 is later changed to BB1 by this step S404. It can be derived that there is an order dependency that it is before. On the other hand, in the control flow graph, when the process including AA1 and the process including BB1 are not directly or indirectly linked, the control unit 11 determines whether the process between AA1 and BB1 is performed in step S404. Can be identified as having no dependencies. When the derivation of the dependency relationship is completed, the control unit 11 advances the processing to the next step S405.

(Step S405)
In step S405, the control unit 11 determines whether or not the processing in step S404 has been completed for all variable pairs. If it is determined that the processing in step S404 has not been completed for all variable pairs, the control unit 11 returns the processing to step S404 and derives a dependency relationship for other variable pairs. Execute. As a result, the control unit 11 executes the dependency derivation process in step S404 for all pairs of variables listed in step S403. When the dependency derivation process is completed for all variable pairs, the control unit 11 determines that the process of step S404 has been completed for all variable pairs, and proceeds to the next step S406.

(Step S406)
In step S406, the control unit 11 aggregates the dependency relationships between the variables obtained by repeating the process in step S404 into the dependency relationships between the paired variable groups extracted in step S403. Thus, the control unit 11 specifies the dependency relationship between the extracted pair variable groups, that is, the order relationship between the two mechanisms 31 corresponding to the extracted pair variable groups.

  FIG. 24B schematically illustrates the dependency relationship obtained between the variables. In the pair P1, an order dependency is obtained in which the variables in the variable group D (Axis001) are first and the variable group D (Axis002) is later. In this case, the control unit 11 specifies in step S406 that the mechanism 31 corresponding to the variable group D (Axis001) has an order relationship that the mechanism 31 corresponding to the variable group D (Axis002) is later. can do. That is, if the order dependency is biased in one direction, the control unit 11 can specify that there is an order relation in that direction between the two mechanisms 31.

  On the other hand, in the pair P2, the variable in the variable group D (Axis001) has a variable pair having an order dependency that the variable group D (Sensor001) comes first, and the variable in the variable group D (Axis001) has There exists a pair of variables having an order dependency that the variable group D (Sensor001) is later. In this case, the control unit 11 may specify that there is a bidirectional order relationship between the two mechanisms 31 corresponding to the extracted pair of variable groups. Alternatively, the control unit 11 employs any one of the two-way order relationships between the two mechanisms 31 corresponding to the extracted pair variable group based on a predetermined method, so that the two mechanisms The order relationship between 31 may be specified.

  For example, the control unit 11 may accept a selection of an order relationship to be adopted among the bidirectional order relationships between the two mechanisms 31 from the user. In this case, the control unit 11 can adopt the order relationship specified by the user as the order relationship between the two mechanisms 31.

  When there is no dependency relationship between any pair of variables, the control unit 11 can specify that there is no order relationship between the two mechanisms 31 corresponding to the extracted pair variable group. Thus, when the identification of the order relationship between the two mechanisms 31 is completed, the control unit 11 advances the processing to the next step S407.

(Step S407)
In step S407, the control unit 11 determines whether or not a series of processing in steps S403 to S406 has been completed for all variable group pairs. When it is determined that the series of processing in steps S403 to S406 has not been completed for all the variable group pairs, the control unit 11 returns the processing to step S403 and performs the processing for other variable group pairs. , A series of processes in steps S403 to S406 is executed. As a result, the control unit 11 executes the process of identifying the order relationship between the mechanisms 31 in steps S403 to S406 for all the pairs of variable groups listed in step S402.

  FIG. 24C schematically illustrates an example of the order relationship of the mechanisms 31 specified based on the order dependency between the variables. As a result of executing the series of processing in steps S403 to S406 for all pairs of variable groups, the control unit 11 can specify the order relationship between all the mechanisms 31 as illustrated in FIG. 24C. When the processing for specifying the order relationship between all the mechanisms 31 is completed in this way, the control unit 11 determines that the processing in steps S403 to S406 has been completed for all pairs of variable groups, and displays the control flow graph. The process for specifying the order relationship of the plurality of mechanisms 31 is terminated.

  As described above, according to the processing procedure according to this modification, it is possible to analyze the control program 221 without using the log data 223 and specify the order relationship of the plurality of mechanisms 31. In the present modification, the step of identifying the dependency of variables in the processing of the control program 221 based on the constructed abstract syntax tree is a step of generating a control flow graph from the constructed abstract syntax tree (step S1413), And a step of identifying the dependency relationship of the extracted variables based on the generated control flow graph (step S1414). However, the step of identifying the dependency relationship of variables in the processing of the control program 221 based on the constructed abstract syntax tree may not be limited to such an example. The control unit 11 may specify the variable dependency in the processing of the control program 221 based on the abstract syntax tree without using the control flow graph.

<4.12>
In the above embodiment, in order to identify the causal relationship between the plurality of mechanisms 31, the strength of the relationship between the plurality of mechanisms 31 (connection state) identified from the state data 222 and the plurality of identified from the control program 221. The order relation of the mechanism 31 is used. However, the information used for specifying the causal relationship need not be limited to only this information. The process analysis apparatus 1 may specify the causal relationship between the plurality of mechanisms 31 by further using information other than the strength of the relationship (connection state) and the order relationship.

  FIG. 25 schematically illustrates an example of the software configuration of the process analysis apparatus 1A according to the present modification. The process analysis apparatus 1A analyzes the acquired mechanism data 250 and the third acquisition unit 116 that acquires the mechanism data 250, and models the processes performed on the production line, thereby determining the order relationship of the plurality of mechanisms 31. A third analysis unit 117 for specifying the process model to be shown is further provided. Further, the relationship identifying unit 115 identifies the causal relationship between the plurality of mechanisms 31 in the process performed on the production line 3 based on the strength of the identified relationship, the order relationship, and the process model. Except for these points, the process analysis apparatus 1 </ b> A is configured in the same manner as the process analysis apparatus 1. Further, the process analysis apparatus 1 </ b> A may have a hardware configuration similar to that of the process analysis apparatus 1.

  FIG. 26 schematically illustrates an example of a process for identifying the process model 252 by analyzing the mechanism data 250. The control unit 11 of the process analysis apparatus 1A operates as the third acquisition unit 116 and acquires the mechanism data 250 before executing step S105. The mechanism data 250 is not particularly limited as long as it is data on at least one of the relative positional relationship of the devices included in each of the plurality of mechanisms 31 and the order in which the devices are involved in the process. It may be a list, a list of sensors for monitoring the operation of the apparatus, information indicating the order of processes, information indicating the installation position of sensors, and the like. Subsequently, the control unit 11 operates as the third analysis unit 117 and identifies the process model 252 by analyzing the mechanism data 250. For example, the control unit 11 refers to the mechanism data 250, specifies the order relationship between the two mechanisms 31, and inputs the specified result to the corresponding cell in the table 251 indicating the relationship between the two mechanisms 31. By completing this table 251, the control unit 11 can specify the process model 252.

  In step S105, the control unit 11 specifies the causal relationship between the plurality of mechanisms 31 in the process performed on the production line 3, based on the strength of the relationship, the order relationship, and the process model. . For example, the control unit 11 may specify the presence / absence of the relationship between the mechanisms 31 based on the product of the identified relationship strength, the order relationship, and the process model. According to this modification, the causal relationship between the plurality of mechanisms 31 constituting the production line 3 can be modeled more accurately by further using the knowledge of the process model specified from the mechanism data 250.

1 ... Process analysis device,
11 ... Control unit, 12 ... Storage unit, 13 ... Communication interface,
14 ... input device, 15 ... output device, 16 ... drive,
111 ... 1st acquisition part, 112 ... 2nd acquisition part,
113 ... 1st analysis part, 114 ... 2nd analysis part, 115 ... Relationship specific | specification part,
2 ... PLC,
21 ... Control unit, 22 ... Storage unit,
23 ... Input / output interface, 24 ... Communication interface,
221 ... control program, 222 ... status data,
223 ... log data,
3 ... Production line, 31 ... Mechanism

Claims (15)

A first acquisition unit for acquiring a plurality of state data relating to states of a plurality of mechanisms constituting the production line;
A second acquisition unit for acquiring a control program for controlling the operation of the production line;
A first analysis unit that identifies a connection state between the plurality of mechanisms by analyzing the acquired state data of the plurality of cases;
Analyzing the acquired control program to identify an order relationship of the plurality of mechanisms;
Based on the connection state and the order relationship identified respectively, a relationship identifying unit that identifies a causal relationship between the plurality of mechanisms in a process performed on the production line;
Comprising
Process analysis device. The relationship specifying unit outputs directed graph information indicating a causal relationship between the specified mechanisms.
The process analysis apparatus according to claim 1. The first analysis unit constructs undirected graph information indicating a connection state between the plurality of specified mechanisms,
The relationship specifying unit creates the directed graph information by applying the order relationship to the undirected graph information.
The process analysis apparatus according to claim 2. The first analysis unit (1) calculates a feature amount from the state data of each case, and (2) calculates a correlation coefficient or a partial correlation coefficient between the feature amounts, thereby Identify the connection status between mechanisms,
The process analysis apparatus according to any one of claims 1 to 3. The second analysis unit specifies an order relation of the plurality of mechanisms based on log data obtained by operating the manufacturing line using the control program.
The process analysis apparatus of any one of Claim 1 to 4. The second analysis unit (1) constructs an abstract syntax tree from the control program, (2) extracts variables and conditional branches related to the mechanisms from the constructed abstract syntax tree, and (3) the control program (4) Refer to the acquired log data, and order the variables based on the execution result of the conditional branch. To identify the order relationship of the plurality of mechanisms,
The process analysis apparatus according to claim 5. The second analysis unit (1) constructs an abstract syntax tree from the control program, (2) extracts variables related to each mechanism from the constructed abstract syntax tree, and (3) adds the abstract syntax tree to the constructed abstract syntax tree. On the basis of the dependency of the variable in the processing of the control program, (4) on the basis of the identified dependency, to identify the order relationship of the plurality of mechanisms,
The process analysis apparatus of any one of Claim 1 to 4. (3) Based on the constructed abstract syntax tree, the step of specifying the dependency relationship of the variables in the processing of the control program includes generating a control flow graph from the constructed abstract syntax tree, Identifying a dependence relationship of the extracted variables based on a control flow graph.
The process analysis apparatus according to claim 7. The state data of each case indicates at least one of torque, speed, acceleration, temperature, current, voltage, air pressure, pressure, flow rate, position, size, and area.
The process analysis apparatus according to any one of claims 1 to 8. The control program is described using at least one of a ladder diagram language, a function block diagram language, a structured text language, an instruction list language, a sequential function chart language, and a C language.
The process analysis apparatus according to any one of claims 1 to 9. The first analysis unit identifies a connection state between the plurality of mechanisms by statistically analyzing the acquired state data of the plurality of cases.
The process analysis apparatus according to claim 1. The first analysis unit specifies the strength of the relationship between the plurality of mechanisms as the connection state.
The process analysis apparatus according to claim 1. A third acquisition unit that acquires mechanism data related to at least one of a relative positional relationship of devices included in each of the plurality of mechanisms and an order in which the devices are involved in the process;
Analyzing the acquired mechanism data and modeling the process performed in the production line, thereby identifying a process model indicating an order relationship of the plurality of mechanisms;
Further comprising
The relationship identifying unit identifies a causal relationship between the plurality of mechanisms in a process performed on the manufacturing line based on the identified connection state, the order relationship, and the process model.
The process analysis apparatus according to claim 1. Computer
Obtaining a plurality of state data relating to the states of a plurality of mechanisms constituting the production line;
Obtaining a control program for controlling the operation of the production line;
Identifying the connection state between the plurality of mechanisms by analyzing the acquired plurality of state data;
Analyzing the acquired control program to identify the order relationship of the plurality of mechanisms;
Identifying a causal relationship between the plurality of mechanisms in a process performed on the production line based on the identified connection state and the order relationship;
Process analysis method to execute. On the computer,
Obtaining a plurality of state data relating to the states of a plurality of mechanisms constituting the production line;
Obtaining a control program for controlling the operation of the production line;
Identifying the connection state between the plurality of mechanisms by analyzing the acquired plurality of state data;
Analyzing the acquired control program to identify the order relationship of the plurality of mechanisms;
Identifying a causal relationship between the plurality of mechanisms in a process performed on the production line based on the identified connection state and the order relationship;
Process analysis program to execute.