CN116796504A

CN116796504A - Production line simulation method based on digital twin and related equipment thereof

Info

Publication number: CN116796504A
Application number: CN202310523242.8A
Authority: CN
Inventors: 高连生; 马思敏
Original assignee: Beihang University
Current assignee: Beihang University
Priority date: 2023-05-10
Filing date: 2023-05-10
Publication date: 2023-09-22

Abstract

The invention provides a production line simulation method based on digital twinning and related equipment thereof, wherein the method comprises the following steps: acquiring a project file corresponding to a target project, wherein the project file comprises a twin equipment model and a topological relation between the twin equipment model; analyzing the project file to graphically display a twin production line model to obtain a twin production line; based on communication connection between a twin device model of each node in the twin production line and physical devices, acquiring real-time operation data of the physical devices; and mapping the production and processing process of the twin production line based on the real-time operation data and the production line scheduling strategy corresponding to the target item to obtain the online monitoring information. The production line simulation system of the universal visual production line scene is constructed through the functions of building a twin production line model, graphically editing and running data-driven simulation in real time, so that the visual scene is adapted to scene changes under different production demands, and the visual scene is quickly constructed or modified, so that the online monitoring function is realized.

Description

Production line simulation method based on digital twin and related equipment thereof

Technical Field

The invention relates to the technical field of simulation systems, in particular to a production line simulation method based on digital twinning and related equipment thereof.

Background

The global manufacturing industry is turning from traditional automated manufacturing to intelligent manufacturing, and with knowledge integration and algorithm training, more work is done through intelligent technology, the core technology of which is based on an information physical integration system to produce intelligent automation with high degree of digitization, networking, intellectualization and integration into marks. The intelligent automation key technology comprises digital twin, wherein the digital twin is based on mapping of physical objects in a digital space, an optimization scheme is obtained through self-learning through an actual data training algorithm, and decision control is realized.

Digital twinning has been well developed in various fields at present, and has also demonstrated great application potential in the industrial field, and many scholars have tried on related applications. The digital twin technology is a theoretical basis for realizing a twin production line, and aims to model and digitize the production line and realize accurate expression and comprehensive presentation in an information space through data assistance. In a twin production line, the digitizing equipment is the core of simulation, and has high requirements on time and logic control. The use of digital twinning technology to rapidly design a production line and verify or retrofit an existing production line to meet new product manufacturing needs is currently a desirable solution in the enterprise digital transformation process.

The digital twin workshops of China are researched, but most of the digital twin workshops depend on foreign production line digital twin software, so that the manufacturing cost is high and the customization effect is weak. The method is limited by the initial limitations of complex production line objects, great development difficulty, complex interconnection protocol and focusing on production line simulation, and the frame and platform level work is built in a rare and general scene. Therefore, under the condition of frequent demand change and rapid demand response, the traditional customized code development mode is difficult to deal with and cannot adapt to different business demands.

Disclosure of Invention

The invention provides a production line simulation method based on digital twinning and related equipment, which are used for solving the defects that a code development mode of a digital twinning production line is difficult to quickly respond and cannot adapt to different service requirements in the prior art, realizing a digital twinning system facing a production line scene, constructing a general production line simulation system for a visual production line scene by establishing a twinning production line model, graphically editing and running a data-driven simulation function in real time, adapting to scene changes under different production requirements, and quickly constructing or modifying the visual scene, thereby solving the production line design and inspection problems faced by the current manufacturing enterprises. And the system is communicated with actual physical equipment, so that the functions of collecting real-time operation data and driving the operation of the twin production line and monitoring the operation of the production line on line are realized.

The invention provides a production line simulation method based on digital twinning, which is applied to an operation system, and comprises the following steps:

acquiring a project file corresponding to a target project, wherein the project file comprises a twin equipment model and a topological relation between the twin equipment model;

analyzing the project file to graphically display the twin production line model to obtain a twin production line;

acquiring real-time operation data of the physical equipment based on communication connection between a twin equipment model of each node in the twin production line and the physical equipment;

and mapping the production and processing process of the twin production line based on the real-time operation data and the production line scheduling strategy corresponding to the target item to obtain on-line monitoring information.

According to the production line simulation method based on digital twinning provided by the invention, after the step of mapping the production and processing process of the twinning production line to obtain the on-line monitoring information based on the real-time operation data and the production line scheduling strategy corresponding to the target item, the method further comprises the following steps:

analyzing operation index data of the twin production line based on the online monitoring information;

Acquiring a preset operation requirement of the target item;

and verifying the design rationality of the twin production line based on the operation index data and the preset operation requirement.

According to the production line simulation method based on digital twinning, the step of verifying the design rationality of the twinning production line based on the operation index data and the preset operation requirement comprises the following steps:

when the operation index data does not meet the preset operation requirement, determining debugging information according to the real-time operation data and the online monitoring information, wherein the debugging information comprises a new twin equipment model and a new topological relation, and the modeling system updates the project file based on the debugging information;

and acquiring an updated project file, and re-executing the step of analyzing the project file until the updated twin production line meets the preset operation requirement, so as to obtain a target twin production line.

According to the production line simulation method based on digital twinning, which is provided by the invention, the step of acquiring real-time operation data of the physical equipment based on communication connection between a twinning equipment model of each node in the twinning production line and the physical equipment comprises the following steps:

Establishing an OPC UA client, a data analysis interface and a data acquisition interface based on an OPC UA protocol, and converting a data acquisition item edited by a user into a data node readable by the OPC UA protocol through the data analysis interface;

establishing communication connection between the OPC UA client corresponding to the twin equipment model and an OPC UA server built in the physical equipment end;

after the communication connection is successful, a data acquisition thread is created, and real-time operation data of the data items of the physical equipment are read in real time through a data acquisition interface.

According to the production line simulation method based on digital twinning, the physical equipment comprises entity equipment and simulation equipment.

The production line simulation method based on digital twinning, provided by the invention, is applied to a modeling system, and comprises the following steps:

when an equipment template file exists in the modeling system, generating a twin equipment model based on a target item and the equipment template file;

sequentially connecting the twin equipment models according to the process flow sequence of the target item, and determining the topological relation between the twin equipment models through topological sequencing;

creating a project file based on the topological relation between the twin equipment model and the twin equipment model, wherein the project file is used for redrawing the twin production line model in an operation system.

The invention also provides a production line simulation device based on digital twinning, which comprises:

the file acquisition module is used for acquiring a project file corresponding to a target project, wherein the project file comprises a twinning equipment model and a topological relation between the twinning equipment model;

the file analysis module is used for analyzing the project file to graphically display the twin production line model so as to obtain a twin production line;

the data acquisition module is used for acquiring real-time operation data of the physical equipment based on communication connection between a twin equipment model of each node in the twin production line and the physical equipment;

and the simulation operation module is used for mapping the production and processing process of the twin production line based on the real-time operation data and the production line scheduling strategy corresponding to the target item to obtain on-line monitoring information.

The invention also provides an electronic device comprising a memory, a processor and a computer program stored on the memory and capable of running on the processor, wherein the processor realizes the production line simulation method based on digital twinning when executing the program.

The present invention also provides a non-transitory computer readable storage medium having stored thereon a computer program which, when executed by a processor, implements a digital twinning based production line simulation method as described in any of the above.

The invention also provides a computer program product comprising a computer program which when executed by a processor implements a digital twin based production line simulation method as described in any of the above.

According to the production line simulation method based on digital twinning and the related equipment, provided by the invention, project files corresponding to target projects are obtained, wherein the project files comprise topological relations between a twinning equipment model and the twinning equipment model; analyzing the project file to graphically display the twin production line model to obtain a twin production line; acquiring real-time operation data of the physical equipment based on communication connection between a twin equipment model of each node in the twin production line and the physical equipment; and mapping the production and processing process of the twin production line based on the real-time operation data and the production line scheduling strategy corresponding to the target item to obtain on-line monitoring information. The production line simulation system is constructed by the functions of graphically editing and operating data-driven simulation in real time through the establishment of a twin production line model, so as to adapt to scene changes under different production demands, quickly construct or modify the visual scene, communicate with actual physical equipment, and realize the functions of collecting real-time operating data, driving the operation of the twin production line and monitoring the operation of the production line on line.

Drawings

In order to more clearly illustrate the invention or the technical solutions of the prior art, the following description will briefly explain the drawings used in the embodiments or the description of the prior art, and it is obvious that the drawings in the following description are some embodiments of the invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic flow chart of a digital twinning-based production line simulation method provided by the invention;

FIG. 2 is a diagram of a digital twinning-based production line simulation system architecture provided by the present invention;

FIG. 3 is a schematic diagram of a digital twinning-based production line simulation system provided by the present invention;

FIG. 4 is one of the flow charts of the operation of the digital twinning-based production line simulation system provided by the present invention;

FIG. 5 is a second flow chart of operation of the digital twinning-based production line simulation system provided by the present invention;

FIG. 6 is a schematic diagram of modeling system software in a digital twinning-based production line simulation method provided by the invention;

FIG. 7 is a schematic diagram of mapping between physical devices and a twin device model in a production line simulation method based on digital twin provided by the invention;

Fig. 8 is a schematic structural diagram of an electronic device provided by the present invention.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is apparent that the described embodiments are some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

The digital twin-based production line simulation method of the present invention is described below with reference to fig. 1 to 8, and is applied to an operating system, and referring to fig. 1, the digital twin-based production line simulation method includes:

step S100, obtaining a project file corresponding to a target project, wherein the project file comprises a topological relation between a twin equipment model and the twin equipment model;

step S200, analyzing the project file to graphically display the twin production line model to obtain a twin production line;

step S300, acquiring real-time operation data of physical equipment based on communication connection between a twin equipment model of each node in the twin production line and the physical equipment;

Step S400, mapping the production and processing process of the twin production line based on the real-time operation data and the production line scheduling strategy corresponding to the target item to obtain on-line monitoring information. And the operation data of the equipment obtained by simulation is stored, calculated and analyzed, visually displayed in a data sheet control, index data taking time as an axis is drawn through a dynamic curve control and a static curve control, and the operation state and the operation trend of the equipment are analyzed.

The present embodiment aims at: the digital twin system for the production line scene of the embodiment constructs a general production line simulation system for the visual production line scene by establishing a twin production line model, graphically editing and running data-driven simulation function in real time so as to adapt to scene changes under different production demands, help users to rapidly design and configure and modify the layout scheme and the process flow sequence of the production line, solve the problem of rapid establishment of the design of the digital twin production line model, and solve the problems of frequent scene modification and rapid response of the flexible manufacturing process summary. And the twin equipment model in the twin production line is communicated with actual physical equipment, real-time operation data are collected, the operation of the twin production line is driven, the production and processing processes of the production line are mapped, and an online monitoring function is realized.

In this embodiment, specific application scenarios are aimed at:

the digital twin technology is utilized to rapidly design the production line and verify or improve the existing production line to meet the manufacturing requirement of new products, and is a solution expected in the digital transformation process of enterprises at present.

As an example, the digital twinning-based production line simulation method may be applied to a digital twinning-based production line simulation system applied to a digital twinning-based production line simulation apparatus.

As an example, referring to fig. 2, the present invention discloses a digital twin-based production line simulation system architecture, which is built in a production line scene and includes: a physical device layer, a communication layer, a digital twin model layer and an application layer.

As an example, the physical device layer contains device entities that perform specific functions such as machining operations or logistics operations, or simulation software that simulates the operation of a device, as a data source for a twin device model. It will be appreciated that the twin line is comprised of physical equipment.

As an example, the communication layer is an important channel for realizing interaction between the physical device layer and the twin model layer, and ensures multi-source data acquisition and real-time performance of data acquisition by specifying a unified data transmission interface.

It can be understood that the communication layer is used for realizing the functions of multi-source data acquisition and data uploading, and because the equipment types on the production line are numerous and the communication interfaces of different factories are also different, the invention realizes multi-source data acquisition facing the production line scene based on an OPC UA (OPC Unified Architecture ) protocol.

As an example, the digital twin model layer is a mapping of a physical device layer, a twin device model and a twin production line model are established, and the operation of the twin model is driven by real-time operation data to achieve the effect of simulation debugging.

The equipment twin model comprises an equipment model, a workstation model and a data model.

As an example, a device model refers to basic attributes of a corresponding physical device, including a device number, a device name, a device work number, a device type, a type of a mapping object (virtual/physical), and the like.

As one example, the workstation model represents the relative position of the equipment in the production line, including equipment objects, input workstations, output workstations, workstation status, and the like.

As an example, the data model represents data formed during the operation of the apparatus, and in the case of a numerical control machine, includes a program name of the operation of the apparatus, an operation state of the apparatus, a spindle rotation speed, tool position information, the number of machined parts, machining time, and the like.

It will be appreciated that the twinning model layer primarily maps the reproduction of the production line operation in the information space and stores the operation data for analysis.

As an example, the application layer realizes the functions of on-line monitoring of the physical production line, production process analysis, inspection of the design scheme of the production line, efficiency analysis and the like by monitoring the state of the twin production line in the operation process based on real-time mapping and simulation operation of the twin model in the information space.

As an example, a production line simulation system based on digital twinning belongs to industrial control software, and the bottom layer needs to be crossed with hardware, so the production line simulation system is realized based on an MFC (Microsoft Foundation Classes, MFC for short, microsoft basic class library) application framework, so as to meet the requirements of industrial software on system stability and safety.

The production line simulation system based on digital twinning comprises a modeling system and an operating system, wherein the modeling system and the operating system both create CAPP class, CMainFrame class, CDoc class and CView class based on an MFC framework; the App class comprises a main thread of program operation and is used for controlling the initialization, the starting, the main message circulation and the like of the application program; the CMainFrame class is responsible for the generation of a main frame window, including a title bar, a menu bar, a toolbar and a status bar; the CDoc class stores the App data and synchronizes the document-based views; the CView class is used for displaying an interface and accepting input and editing of a user.

Referring to FIG. 3, the modeling system includes an editing module, and the runtime system includes a runtime module, a communication module, and a data resource pool module. The data resource pool module and the communication module are logically separated from the operation module, but are integral in actual operation.

As one example, an editing module is user-oriented for combining and defining manufacturing resource templates, defining equipment physical models, editing a production line topology, and constructing an operating strategy for the production line. The physical device is "connected" to the twin device model through an OPC UA communication module. The twin equipment model consists of an equipment physical model, a workstation model and a data model.

As one example, the device physical model includes a device name, number, device type, process flow number, data collection information, primitive information, and the like. The graphic primitive information is an interface of user interface operation equipment, and comprises graphic primitive position information, graphic primitive drawing, graphic primitive moving, graphic primitive scaling and other operations. The data acquisition information is a data item which is edited by a user and is wanted to be acquired, a data model is established according to the data acquisition information, and state changes in the running process of equipment and data changes of basic components are represented through the data model, for example, a machine tool data model comprises a spindle rotating speed, a spindle multiplying power, an actual feeding speed, an absolute coordinate, a running state, running time, machining time and the like; the robot data model contains the rotation angle and rotation speed of each shaft, the running state, the running time and the like.

As an example, the communication module includes an OPC UA client and a data acquisition interface, where data is periodically requested from a physical device (a simulation device or an entity device); one aspect drives the operation of the twin line model and persists the data for other application services.

As an example, the data resource pool module is responsible for processing, calculating and storing data in the operating system, including processing data generated by the physical device layer and device status information, and the processed data is used as a data support for analyzing the production line scheme. The data resource pool supports distributed application through data calculation and analysis and data storage and transmission, and indexes such as production beats and utilization rate of each device are statistically displayed in a visual form through analyzing data of physical devices in the running process.

The data resource pool is structurally composed of a data buffer area, a database, a data transfer unit and a data processing unit, as shown in fig. 3. The data sources of the data cache area are equipment model and workstation model data of an operating system and real-time operating data generated by physical equipment read by a communication module. The real-time running data in the memory is stored in the equipment data model, and the model is stored in a structure of a circular queue CSamplDataQueue. The data in the data buffer has two streams: on one hand, the image update in the running environment is driven, namely, a structural body (comprising CNCstruct, ROBstruct, PLCstruct) of the data model is input into a data model queue, and on the other hand, the data is stored into a database and a data file through data transfer, and is used as data backup so as to facilitate later replay and inquiry based on the data. The database is used for batch storage of real-time operation data. Since in an industrial data acquisition environment, industrial data acquisition systems are primarily directed to structured data or semi-structured time series data acquisition. The data processing unit is used for performing various operations and data processing, such as calculating the running beat of the equipment and the indexes of the equipment OEE (Overall Equipment Effectiveness, comprehensive efficiency of the equipment), time utilization rate, performance utilization rate and the like, and storing the indexes in a lasting manner. Intuitively displaying the operation data of all the devices through a data sheet control on a system interface; the dynamic curve control shows a graph drawn dynamically by taking time as an X axis and index values as a Y axis, and the running states of the equipment at different times are compared through index data; the static curve control is used for designating equipment and indexes by a user, wherein the time is taken as an X axis, and the index value is taken as a Y axis, so that the running trend of different equipment is intuitively displayed. The index data provides basis for analysis of the design scheme of the production line and is used as a standard for checking the rationality of the design scheme of the production line. The data transfer area stores source data and processed data analysis results through the format of an XML file.

As an example, the operation module is an operation environment of a twin production line, and according to a production line model designed by the editing module, the production and processing process of the production line is mapped based on the data information of the physical equipment and the scheduling policy of the production line, so as to realize an online monitoring function.

As an example, the running system further includes a first file management module, where the first file management module is responsible for reading the production line project file, and analyzing the production line project file to form a twin production line model. And the obtained primitive information of the twin equipment model and the interface drawing interface realize redrawing of the twin production line model.

The production line simulation method based on digital twinning is applied to an operation system and comprises the following specific steps:

step S100, obtaining a project file corresponding to a target project, wherein the project file comprises a topological relation between a twin device model and the twin device model.

As one example, the project file is a file storing a twin device model and a twin line model, wherein the twin line model includes a topological relationship between the twin device model and the twin device model.

And step 200, analyzing the project file to graphically display the twin production line model, so as to obtain a twin production line.

As one example, a user generates a twin line model by selecting a target line project, by an parsing interface of the project file, the twin line model including a connection relationship between a twin device model and the twin device model, and displays the line model in a graphical form by a primitive drawing interface.

As an example, in the running system, the project file is parsed by InitPrjByRiff () function, and the project attribute data block, the device data block group, the station data block group, the start/end flag primitive data block group, and the connection line data block group are parsed first according to the data block type. And then sequentially analyzing the twin equipment model data blocks contained in the equipment data block group and the workstation data blocks contained in the workstation data block group, and the other is the same. Taking a twin device model as an example, each twin device data block comprises a plurality of attribute data blocks, and the data blocks are analyzed sequentially according to data names, and the other data blocks are similar.

As one example, in a running system, the ondrow () function redraws a twin line model on an interface according to the primitive information, start/end primitive information, and connection line primitive information of the twin device model.

And step S300, acquiring real-time operation data of the physical equipment based on communication connection between the twin equipment model of each node in the twin production line and the physical equipment.

As an example, in a running system, the simulation running process is implemented by multiple threads because of high requirements on data real-time and reasonable utilization of computing resources, and the simulation running flow is as shown in FIG. 4. The simulation running thread ThreadUpdateStateMachine is responsible for creating communication connection between the physical equipment and the twin equipment model, initializing a station state, running scheduling of the twin production line and refreshing a running interface based on the station state. The data acquisition thread ThreadDataAcquisition is responsible for reading data items in the physical equipment, filling the data items into the data model of the twin equipment model, and caching the data models of all the equipment in a memory in a data queue. The data storage thread data file is responsible for storing the data queues cached in memory in a database or data file.

As an example, the step of acquiring real-time operation data of the physical device based on a communication connection between a twin device model of each node in the twin production line and the physical device includes:

Step S310, an OPC UA client, a data analysis interface and a data acquisition interface are established based on an OPC UA protocol, and data acquisition items edited by a user are converted into data nodes readable by the OPC UA protocol through the data analysis interface;

step S320, establishing communication connection between the OPC UA client corresponding to the twin device model and an OPC UA server built in the physical device;

and step S330, after the communication connection is successful, creating a data acquisition thread, and reading real-time operation data of the data item of the physical equipment in real time through a data acquisition interface.

As one example, the runtime system creates an OPC UA client to communicate the twin device model with the physical device (simulated device/entity device), collects related data items through the data collection interface, the data items being the portions contained in the data model of the twin device model. The data queue is used for driving the twin production line to run and display on a running interface, and is stored through a database or a data file for application services (such as equipment utilization analysis and production line rationality check).

As an example, data collection is performed at a frequency specified by the user, defaulting to 250ms, and a data queue is formed in memory after collection.

Specifically, after the simulation running thread is created and started, an OPC UA client object corresponding to the twin equipment model is dynamically created according to IP/Port attribute data of the equipment model, and a data analysis interface, a data acquisition interface and a data subscription interface are designed based on an OPC UA protocol. And the client created by the running system is sequentially connected with the OPC UA server of the physical equipment.

It should be noted that, there are two main forms of data interaction between the OPC UA server and the client: one is a direct transmission mechanism, where a client directly reads or writes one or more node attributes stored in a server address space; and the other is a subscription mechanism, and the client subscribes and listens to the data continuously changed in the server.

As an example, after starting the data acquisition thread, the data parsing interface converts the data items required for the data model in the twin device model into a client accessible physical device server end node NodeId. The data acquisition interface implements a direct transmission mechanism to obtain values of data items in the data model of the device. The data subscription interface realizes monitoring when the data items change under the subscription mechanism. The data acquisition thread sequentially calls the data acquisition interfaces corresponding to the OPC UA clients according to the equipment sequence, and stores the data model in the memory according to the time sequence until the allocated space is saturated. If the memory space is saturated, the data storage thread is started.

After the memory space is saturated, the data storage thread reads the data model data stored in the memory, connects the database and stores the data model data into the MySQL database in batches, stores the data model data into an off-line file by using an XML file at regular intervals, and clears the memory after the storage is completed for continuous collection of the data.

In this embodiment, real-time data is stored and analyzed through the data resource pool, a decision basis is provided for application services, and a production line configuration scheme is evaluated. The operation module creates three threads of data acquisition, data storage and simulation operation to respectively execute the reading function of equipment data, the storage function of real-time data and the function of controlling the simulation operation process to realize state mapping in the realization process, thereby further realizing the functions of equipment monitoring, visual demonstration, production line analysis and optimization.

Step S400, mapping the production and processing process of the twin production line based on the real-time operation data and the production line scheduling strategy corresponding to the target item to obtain on-line monitoring information.

In the operation system, the system establishes a data acquisition sequence around a physical model queue of the twin device, and the data acquisition sequence is used for driving simulation operation and state demonstration. And the operation data of the equipment obtained by simulation is stored, calculated and analyzed, visually displayed in a data sheet control, index data taking time as an axis is drawn through a dynamic curve control and a static curve control, and the operation state and the operation trend of the equipment are analyzed.

As an example, referring to fig. 5, in the operating system, firstly, a project file to be debugged is selected, the system reads in the project file and forms a twin production line model by analyzing a RIFF (Resource Interchange File Format, resource exchange archive standard) file through initialization at an interface of the operating system, after performing simulation operation, the operating system dynamically creates a connection between a client and a physical device corresponding to an IP/Port in sequence based on an IP and Port number (Port) attribute value stored in each twin device model, and opens a simulation thread threadupdatestamachine after the connection is successful, and synchronously creates a data acquisition thread ThreadDataAcquisition and a data storage thread ThreadWriteDataFile. In the simulation running thread, the workstation state is initialized to be a waiting state in sequence, the workstation state is updated by combining the updating of equipment state data and the scheduling strategies of the input workstation and the output workstation, and the change of the workstation state is displayed through the color change of the picture frame in the interface refreshing function. The data acquisition thread circularly executes the acquisition of the equipment data items and updates the equipment state. The data storage thread executes the storage function when the storage capacity reaches the specified requirement, otherwise the thread is suspended.

As one example, five stable states are created for each workstation in the operating system, including: shutdown, waiting, processing completion, blocking. And establishing a switching mechanism of the workstation state in the workstation model through a finite state machine mode. When the acquired equipment state is the waiting state, namely a starting signal is sent, the workstation is switched to the waiting state. When the equipment executes a processing program (namely, the state of the equipment is processing), the system acquires a signal of the operation of the equipment, judges whether the material buffer area has materials, if so, sends a signal of the arrival of the materials, and the current station switching state is a processing state. When the station inputs materials, there are the following two cases: a. the current state of the station is not changed when the capacity of the station material buffer area is full; b. the capacity of the station material buffer area is not full, and the station material buffer area can be continuously input. When the program execution ends, that is, a processing completion signal is sent, the state is switched to the "processing completion" state. When the workstation is in the "processing complete" state, there are three situations: a. judging whether the output work station array has work stations in a waiting state, if so, outputting, namely switching the state into the waiting state; b. if the output station array has no station in the waiting state, setting the station in the blocking state, and waiting for the judgment of the output of the material when the material stays in the station; c. if no workstation is output, the workstation is proved to be the last process and the equipment state is changed to a "waiting" state. When the equipment is in a blocking state, whether a work station capable of outputting exists or not is continuously judged, and if so, the equipment is switched to a processing completion state. If the device state is received as "pause" in the "blocking" state, the device is immediately switched to the "blocking" state, and the device is waited for to resume operation.

In the simulation running thread, initializing all work station states to wait, firstly reading equipment state data from all collected data items, and judging whether the current work station can send output signals to the output work station by combining material input/output signals, work station state switching strategies and work station scheduling strategies in the scheduling process. When station a transitions from the idle state to the processing state, its material buffer "material" flag becomes FALSE, and waits until the processing is completed, and when it has an output station B and it is in the idle state, it is considered that it can output, it is switched from the "processing completed" to the "waiting" state, at which time the material buffer of the output station B is set to TRUE, and an output signal is triggered, which also serves as a state switching condition of the output station B. And when all the workstation state data are updated, calling the animation demonstration interface, and demonstrating the operation process and equipment state mapping of production and processing by changing the frame colors of the equipment graphic elements on the interface through the workstation state. And when the simulation operation is finished, the simulation operation thread assigns a shutdown state for each workstation.

As an example, after the step of mapping the production process of the twin production line to obtain the online monitoring information based on the real-time operation data and the production line scheduling policy corresponding to the target item, the method further includes:

A1, analyzing operation index data of the twin production line based on the online monitoring information;

step A2, obtaining a preset operation requirement of the target item;

and step A3, verifying the design rationality of the twin production line based on the operation index data and the preset operation requirement.

The twin production line model is composed of a twin device model and a topological structure formed by connecting the twin device model, and the mapping of the twin device model realizes device simulation under data driving and embodies the operation details of the device. The mapping of the digital twin production line model realizes the previewing of the production process and the verification of the production line layout, and reflects the running state of the production line. That is, the operating system monitors the production line state and production data based on the real-time operating data of the physical equipment and the operating data of the twin production line, and further realizes production process analysis and inspection of the production line design scheme.

Specifically, based on the on-line monitoring information, the operation index data of the twin production line is analyzed, whether the operation index data meets the preset operation requirement of a target item or not is intuitively judged by drawing an index curve graph through a data table control, a dynamic curve control and a static curve control, and the design rationality of the twin production line is verified. The preset operation requirement may be a requirement of production efficiency, processing cost, etc., and is determined according to an actual target item, which is not specifically limited herein.

Therefore, in this embodiment, the digital twin-based production line simulation system has two application scenarios, namely, design and debugging can be performed for an unformed production line scheme, and the rationality of the design is checked based on actual operation data; secondly, mapping the existing production line, and realizing online monitoring and production efficiency analysis of the production line.

As an example, the step of verifying the design rationality of the twin line based on the operation index data and the preset operation requirement includes:

step A31, when the operation index data does not meet the preset operation requirement, determining debugging information according to the real-time operation data and the online monitoring information, wherein the debugging information comprises a new twin equipment model and a new topological relation, and the modeling system updates the project file based on the debugging information;

and step A32, acquiring an updated project file, and re-executing the step of analyzing the project file until the updated twin production line meets the preset operation requirement, so as to obtain the target twin production line.

As one example, a twin line model implements a mapping of line physical layout, scheduling policies, and operating states. The physical layout is the display of the connection relation of the devices on a system interface, the scheduling strategy represents the topological structure representation formed by the material flow relation among the devices, and the running state represents the state demonstration of the production line in the running process.

When the operation index data does not meet the preset operation requirement, determining debugging information for adjusting the twin production line model according to the real-time operation data, the online monitoring information and the operation index data. It can be understood that when the current twin line model does not meet the preset requirement of the target project, the selection, position, number, model and the like of the twin equipment model in the current twin line model can be adjusted, new project files are created by the adjusted data, the current project files are updated by the new project files, a new twin line model is created based on the updated project files, and online monitoring, production line design rationality verification and the like are performed.

At present, most digital twin systems are applied to the existing physical production line, and a one-to-one reduction twin production line is constructed in an information space so as to monitor the physical production line on line and form an optimization scheme for data analysis of the physical production line. In the embodiment, the application scene of the digital twin system is advanced to a design stage, a twin production line model is graphically designed under the condition that no physical production line object exists, operation data are obtained by connecting physical equipment or simulation equipment forming the production line, and the operation of the twin production line is driven, so that the functions of on-line monitoring and analysis of the operation data of the production line are realized.

Compared with the current code development mode of the digital twin production line which is difficult to quickly respond and cannot adapt to different service requirements, the invention obtains a project file corresponding to a target project, wherein the project file comprises a topological relation between a twin equipment model and the twin equipment model; analyzing the project file to graphically display the twin production line model to obtain a twin production line; acquiring real-time operation data of the physical equipment based on communication connection between a twin equipment model of each node in the twin production line and the physical equipment; and mapping the production and processing process of the twin production line based on the real-time operation data and the production line scheduling strategy corresponding to the target item to obtain on-line monitoring information. The production line simulation system is constructed by the functions of graphically editing and operating data-driven simulation in real time through the establishment of a twin production line model, so as to adapt to scene changes under different production demands, quickly construct or modify the visual scene, communicate with actual physical equipment, and realize the functions of collecting real-time operating data, driving the operation of the twin production line and monitoring the operation of the production line on line.

Based on the first embodiment, a second embodiment of a production line simulation method based on digital twinning is provided, and the production line simulation method based on digital twinning is applied to a modeling system, and specifically comprises the following steps:

step S500, when an equipment template file exists in the modeling system, a twin equipment model is generated based on a target item and the equipment template file;

step S600, sequentially connecting the twin equipment models according to the process flow sequence of the target project, and determining the topological relation between the twin equipment models through topological sequencing;

step S700, creating a project file based on the topological relation between the twin equipment model and the twin equipment model, wherein the project file is used for redrawing a twin production line model in a running system.

As an example, referring to fig. 5, fig. 5 is a flow chart of a production line simulation system operation based on digital twinning.

Modeling systems are work environments that users must rely on to edit production line designs. The method is used as a development environment and is responsible for the work of creating and managing equipment templates, creating and managing twin equipment models, editing twin production line models, setting production line projects and the like. There are two design ideas in the production line design stage: the method comprises the steps of designing the layout and the equipment configuration of the production line completely and independently, and restoring the physical production line configuration in the information space based on the existing physical production line.

As an example, the composition and operation of the modeling system is shown in fig. 6. The modeling system comprises a resource management library, a production line editing module and a second file management module.

As one example, the resource management library is responsible for creation, editing, and presentation of device template models. The device template is multiplexed to improve the expandability and reusability of the twin device model. The device template includes a device template number, a device template name, a device template type, and picture information to form a device template model. And the resource management library is used for arranging and displaying template information on the resource management library interface by reading the file.

The device template model creates a field with a field name being an attribute name for each item of data based on device template information input by a user at a system interface, and forms a sub-data block. And creating a data block with a field name being a template name for each equipment template, wherein the data block contains sub-data blocks of the template attribute to form a tree structure for storage.

As an example, the production line editing module is mainly responsible for creating a twin device model based on a device template, the production line editing module is mainly responsible for creating the twin device model based on the device template, drawing and editing the production line model on a system interface, and building the production line model based on an AOV network.

As an example, the second file management module is mainly responsible for storage parsing of resource files and project files, and stores device templates and production line project information in the form of files in the system. The production line project information includes project names, storage addresses of project files, creator and creation time, and twinned production line models.

The resource file is a file storing a device template, the content of the resource file is edited by a user on a system interaction interface, and the defined device template is displayed on a resource management library interface in a picture form. The project file is a file storing a twin equipment model and a twin production line model.

As an example, the production line editing module designs the positions and the number of twin equipment models according to the process flow sequence, and the directional logistics path established after the formation of the links forms a production line operation scheme. For the process flow arrangement of the production line with strict sequence relation, a directed acyclic graph is used for modeling to describe, the vertexes are used for representing activities, and the directed edges are used for representing the precedence relation among the activities. The inter-restriction relationship between the processes is represented by a directed acyclic graph, wherein vertices represent stations, each station has and performs a process, and arcs represent preferential restriction relationships between stations, the graph structure being referred to as an AOV network (Activity On Vertex Network). And constructing a topological structure model of the production line based on the AOV network, taking the workstation object as a node, and constructing an input stream and an output stream of the workstation by using virtual connecting line nodes. Given workstation node M _i Station node M _j These two nodes, if there is a slave node M _i The output workpiece can reach the node M _j Is further processed, then slave node M _i To node M _j A directional connecting edge exists between the two<M _i, M _j >Indicating that the processing sequence of the workpiece is M _i The station performs processing, and the processed parts are conveyed to M through a conveyor belt or logistics equipment _j Station re-executionFurther processing, under the configuration of the work station and the design of the process flow, the production line AOV model is formed.

The graphic element component class CPixel provides an editing interface for graphic scaling and moving, is established based on the CObject class, invokes the interface through mouse operation, and realizes the graphic editing process in combination with an interface refreshing mechanism.

As one example, when a device template file exists in the modeling system, the user selects a device template in the resource management library interface and further instantiates a visual twin device model that is presented in the form of primitives at the modeling system interface. The twin production line model is formed based on connection of equipment graphic elements, connection line graphic elements and starting/ending graphic elements, the topological relation of each twin equipment model is determined through topological sequencing based on structural description of an AOV network, and the topological relation between the twin equipment models is finally stored as a project file.

As one example, in a modeling system, the system queries whether a device template file exists, reads in if so, otherwise alerts the user to create a device template. In a modeling system, a twin device model is generated based on device template instantiation and content editing by a user on an interactive interface, including a device model, a workstation model, and a data model.

The modeling system realizes addition and deletion of the equipment templates PROL_Res through a resource management class ResManager. And establishing a model according to the equipment template number, the equipment template name, the equipment template type and the picture information on the design resource template of the system interactive interface, wherein the picture of the type of ". Jpg", ". Bmp", ". Jpeg", ". Icon", ". Png", ". Gif" is required to be locally imported by a graphic primitive user, and other picture formats are not supported. The device template is bound with the picture, and the system loads and displays the thumbnail with the device template information on the resource management library interface by analyzing the RIFF resource file.

As an example, when a device template file exists in the modeling system, a specific process of generating a twin device model based on a target item and the device template file is as follows:

The modeling system creates a twin device model based on a device template, gives a device name, a device number, a device work number, a device IP and Port, a type of physical device (simulation device/entity device) and a collected data type to the currently created device through an interactive interface, and displays a picture associated with the device on the interface of the modeling system after the creation is completed. Mapping of physical devices and twin device models as in fig. 7, when a device physical model is created, the system synchronously generates a corresponding workstation model, and device information in the workstation model is matched with the created device model.

The twin device model is encapsulated in the form of a graphical component, i.e. a device primitive is formed. And editing the position and the primitive size of the twin equipment model on the system interface through dragging equipment primitives according to the production equipment and the process flow required by the target project. The method comprises the steps of placing a starting graphic element and an ending graphic element at the inlet and the outlet of a production line model to serve as the material inlet and the material outlet of the production line, sequentially connecting the two graphic elements through a connecting line according to the process flow sequence until all the components of the production line are configured, and storing files, namely closing the editing state.

It should be noted that, in the modeling system, the device physical model CDevCtrl is encapsulated in the form of a primitive component, so that the physical model realizes the interfaces of drawing, moving and scaling operations based on the CPixel class, and can be displayed on the interface of the modeling system. Also, a start/end primitive class and a connection line primitive class are created based on the CPixel class, and interfaces such as drawing, moving, scaling and the like are realized in the respective classes. On the modeling system interface, the user edits the twin line model by creating these device primitives, start/end primitives, and connection line primitives. After the twin production line model is built, the system traverses the digital twin production line model based on the AOV network through topological sorting, and the input and output work stations of the current work station are stored in each work station model. Because the relationship between the stations represents the process flow sequence and the line configuration (i.e., the number of equipment configured per process flow), a basis is established for the operation of the twin line.

As an exampleA corresponding workstation model is created based on the device physical model, the workstation model being a functional map of the physical device (virtual device/actual device). In the production line, the equipment comprises logistics equipment, processing equipment and storage equipment, and because the design only focuses on the running condition of the production line, various types of equipment are uniformly mapped into work stations, and the work stations comprise models for input and output work stations, state transition and time propulsion step sizes of the current work stations. Building a unified logic model abstract expression for a workstation into seven parameters: s=<S _in ,S _out ,W _in ,C,K,t _mach ,Rule>. Wherein S is _in Input station set for current station S _out And outputting the work station set for the current work station. C represents a set of work station states to represent transient characteristics of the work station, only one state of the work station exists at a time. I.e., c= { OFF, wait, working, block, done }, the set of states describes five states of the workstation element in the production line, shutdown, wait, work, blocking, and processing completion, respectively. K represents a device state set used for reflecting the running condition of the device, namely K= { Working, waiting, stop, alarm }, and the state set describes four states of Working, waiting, stopping and alarming of the device element in the production line respectively. The station state is based on the mapping of the equipment state, but the accuracy of data acquisition determines that the equipment state cannot be completely used as the basis of the mapping of the station state, so that the equipment state is used as a switching signal and is simultaneously assisted with a state switching strategy to jointly determine the switching of the station state. W (W) _in For feeding material, e.g. as a group of work pieces or as an empty set, i.et _mach For the work time step of the work station, the work station is represented at t _mach (S) state switching occurs after time based on current state, i.e., t _mach (S) =t U { + infinity is provided and (3) is performed. Rule is a state switching Rule, including processing time, material input and output Rule, station switching Rule, etc.

As one example, in a modeling system, a storage and reading interface for resource files and project files is created, the resource files and project files being of the RIFF file having a hierarchical structure. Each hierarchy is a block (Chunk), which is the basic unit that makes up the RIFF file, and consists of a block ID, a block memory size, and data content. The data block group consists of a plurality of data blocks, and the type of the data block group is LIST. Taking a project file as an example, a project file data block comprises a project attribute data block group, a project attribute data block group and a project station data block group, wherein the ID of the project attribute data block group is a project name, and the data block comprises a project creator, a project creation time sub-data block and a project creation time sub-data block group of the project station. The equipment sub-data block group consists of a plurality of twin equipment model sub-data blocks, each twin equipment model data block further comprises a plurality of equipment attribute data blocks, and the workstation data block group is the same.

In this embodiment, the modeling system models different device objects based on device templates in the resource management library, the device objects being used to graphically build a configured twin line, form a twin line model, and construct a line operation policy. The modeling system is a general tool for classifying and graphically designing production line model projects according to projects, and each project defines a production line model so as to adapt to different services and requirements of different users. The graphical configuration mode aims at realizing the purpose of helping a user to rapidly design and configure the digital twin production line model and modifying the layout scheme and the process flow sequence of the production line, on one hand, the problem of rapid design establishment of the digital twin production line model is solved, and on the other hand, the problem of frequent scene modification and rapid response in the flexible manufacturing process is solved. That is, the modeling system has a highly open and modularized system structure, so that enterprises can freely customize a production line digital twin system to design a production line scheme; the system provides a platform for designing and debugging the virtual production line, and the user independently configures the equipment to realize data transmission through the unified acquisition interface.

The digital twin-based production line simulation device provided by the invention is described below, and the digital twin-based production line simulation device described below and the digital twin-based production line simulation method described above can be correspondingly referred to each other.

the data acquisition module is used for acquiring real-time operation data of the physical equipment based on communication connection between a twin equipment model of each node in the twin production line and the physical equipment; the physical equipment comprises entity equipment and simulation equipment;

And/or the device further comprises:

the data analysis module is used for analyzing the operation index data of the twin production line based on the online monitoring information;

the information acquisition module is used for acquiring the preset operation requirement of the target item;

and the production line verification module is used for verifying the design rationality of the twin production line based on the operation index data and the preset operation requirement.

And/or, the production line verification module further comprises:

the production line verification sub-module is used for determining debugging information according to the real-time operation data and the online monitoring information when the operation index data does not meet the preset operation requirement, so that a modeling system can update the project file based on the debugging information, wherein the debugging information comprises a new twin equipment model and a new topological relation;

and the production line updating sub-module is used for acquiring the updated project file, and re-executing the step of analyzing the project file until the updated twin production line meets the preset operation requirement, so as to obtain the target twin production line.

And/or, the data acquisition module further comprises:

the connection creation sub-module is used for establishing an OPC UA client, a data analysis interface and a data acquisition interface based on an OPC UA protocol, and converting a data acquisition item edited by a user into a data node readable by the OPC UA protocol through the data analysis interface;

the communication connection sub-module is used for establishing communication connection between the OPC UA client corresponding to the twin equipment model and an OPC UA server built in the physical equipment end;

and the data acquisition sub-module is used for creating a data acquisition thread after the communication connection is successful, and reading the real-time operation data of the data item of the physical equipment in real time through the data acquisition interface.

And/or the device further comprises:

the modeling system comprises a model creation module, a modeling module and a storage module, wherein the model creation module is used for generating a twin equipment model based on a target item and equipment template files when the equipment template files exist in the modeling system;

the model topology module is used for sequentially connecting the twin equipment models according to the process flow sequence of the target project, and determining the topological relation between the twin equipment models through topological sequencing;

the file production module is used for creating a project file based on the topological relation between the twin equipment model and the twin equipment model, wherein the project file is used for redrawing the twin production line model in the running system.

The specific implementation manner of the production line simulation device based on digital twin is basically the same as that of each embodiment of the production line simulation method based on digital twin, and is not repeated here.

Fig. 8 illustrates a physical structure diagram of an electronic device, as shown in fig. 8, which may include: processor 810, communication interface (Communications Interface) 820, memory 830, and communication bus 840, wherein processor 810, communication interface 820, memory 830 accomplish communication with each other through communication bus 840. The processor 810 may invoke logic instructions in the memory 830 to perform the steps of a digital twin based production line simulation method.

Further, the logic instructions in the memory 830 described above may be implemented in the form of software functional units and may be stored in a computer-readable storage medium when sold or used as a stand-alone product. Based on this understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art or in a part of the technical solution, in the form of a software product stored in a storage medium, comprising several instructions for causing a computer device (which may be a personal computer, a server, a network device, etc.) to perform all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a random access Memory (RAM, random Access Memory), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

In another aspect, the present invention also provides a computer program product comprising a computer program, the computer program being storable on a non-transitory computer readable storage medium, the computer program, when executed by a processor, being capable of executing the steps of the digital twin-based production line simulation method provided by the methods described above.

The specific implementation manner of the computer program product of the present application is basically the same as the above embodiments of the production line simulation method based on digital twin, and will not be described herein.

In yet another aspect, the present application also provides a non-transitory computer readable storage medium having stored thereon a computer program which, when executed by a processor, is implemented to perform the steps of the digital twin based production line simulation method provided by the methods described above.

The specific implementation manner of the storage medium of the present application is basically the same as the above embodiments of the production line simulation method based on digital twin, and will not be described herein.

The apparatus embodiments described above are merely illustrative, wherein the elements illustrated as separate elements may or may not be physically separate, and the elements shown as elements may or may not be physical elements, may be located in one place, or may be distributed over a plurality of network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art will understand and implement the present application without undue burden.

From the above description of the embodiments, it will be apparent to those skilled in the art that the embodiments may be implemented by means of software plus necessary general hardware platforms, or of course may be implemented by means of hardware. Based on this understanding, the foregoing technical solution may be embodied essentially or in a part contributing to the prior art in the form of a software product, which may be stored in a computer readable storage medium, such as ROM/RAM, a magnetic disk, an optical disk, etc., including several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the method described in the respective embodiments or some parts of the embodiments.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A digital twinning-based production line simulation method, applied to an operating system, the method comprising:

2. The method for simulating a production line based on digital twinning according to claim 1, wherein after the step of mapping the production process of the twinning production line to obtain on-line monitoring information based on the real-time operation data and the production line scheduling policy corresponding to the target item, the method further comprises:

Acquiring a preset operation requirement of the target item;

3. The digital twin based production line simulation method according to claim 2, wherein the step of verifying the design rationality of the twin production line based on the operation index data and the preset operation requirement comprises:

4. The digital twinning-based production line simulation method according to claim 1, wherein the step of acquiring real-time operation data of the physical device based on communication connection between a twinning device model of each node in the twinning production line and the physical device comprises:

5. The digital twinning-based production line simulation method according to any one of claims 1-4, wherein the physical devices include a physical device and a simulation device.

6. The digital twinning-based production line simulation method of claim 1, applied to a modeling system, the method comprising:

7. A digital twinning-based production line simulation device, the device comprising:

8. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor implements the digital twinning-based production line simulation method of any one of claims 1 to 6 when the program is executed by the processor.

9. A non-transitory computer readable storage medium having stored thereon a computer program, which when executed by a processor implements the digital twin based production line simulation method according to any of claims 1 to 6.

10. A computer program product comprising a computer program which, when executed by a processor, implements a digital twinning-based production line simulation method according to any one of claims 1 to 6.