A method for constructing and dynamically configuring multi-dimensional and multi-level models of digital twin workshops

Abstract

The present invention discloses a method for constructing and dynamically configuring a multi-dimensional and multi-level model of a digital twin workshop, specifically: defining the multi-dimensional virtual model of a digital twin workshop into three dimensions: information model, visualization model, and mechanism model, wherein the visualization model is a visual display of the multi-dimensional and multi-level model of the digital twin workshop, the mechanism model expresses the production operation logic and mechanism of the production workshop, and the information model integrates the production workshop operation data; after constructing the multi-dimensional and multi-level model-related sub-models of the digital twin workshop, the multi-dimensional and multi-level models are integrated in three stages: simulation verification before execution, real-time monitoring during execution, and optimization iteration after execution. The present invention realizes the construction of a multi-dimensional and multi-level model of a digital twin workshop that can be used for workshop operation control, optimization, and other applications, clarifies the basic steps of modeling, improves modeling efficiency, and improves model accuracy.

Description

Technical Field

[0001] The present invention belongs to the technical field of discrete manufacturing system modeling and simulation, and specifically relates to a method for constructing and dynamically configuring a multi-dimensional and multi-level model of a digital twin workshop. Background Art

[0002] Discrete manufacturing systems are the most widely used form of manufacturing. They are widely used in the production of everything from high-speed trains and aviation equipment to electronic products and daily necessities. However, on the one hand, the production objects of discrete manufacturing systems are highly coupled with the system, and both products and systems may undergo uncertain changes. On the other hand, the constant changes in market demand have also brought new production demands, making the current discrete manufacturing system more and more dynamic and uncertain, which has brought huge challenges to the efficient operation and management of discrete manufacturing systems, and brought about the need to combine workshops with NewIT technologies to build smart workshops.

[0003] With the introduction of digital twin technology, its emphasis on various types of data machine tools, dynamic evolution of the entire life cycle, and model-based optimization iteration are very suitable for the construction of smart workshops enabled by NewIT. The production workshop based on digital twins is called a digital twin workshop. To build a digital twin workshop, it is first necessary to build a virtual model of the workshop to map the physical workshop and carry a series of workshop applications. The virtual model is characterized by multi-dimensionality, dynamics, and high fidelity, which can meet the needs of digital twin workshops for process evaluation, simulation operation, and optimization iteration based on real-time data. To this end, a method is needed to build a multi-dimensional virtual model of a digital twin workshop and enable it to respond quickly to changes.

[0004] In the related art, the construction of a multi-dimensional virtual model of a workshop usually considers how to collect real-time data to drive the update of the visualization model, or establish a two-way data transmission channel between the virtual and the real to realize the linkage control of the production process, and explores how to update the model based on the changes in dynamic data during the real-time operation of the equipment. The prior art with patent number CN202010602613.8 discloses a discrete workshop production plan evaluation method based on combined weighting. It is specifically disclosed that by constructing a workshop production plan evaluation index system, the simulation basic data is obtained after the simulation is completed, and the simulation evaluation index is calculated by the production plan evaluation index system, the weight of each index value is obtained by combining and weighting the index system, and the evaluation result of the current scheme is obtained by fuzzy comprehensive evaluation. However, when a new workshop is built or a production disturbance occurs, especially after the equipment is iterated, updated, and re-layouted, the process of building or reconfiguring the digital twin workshop model involves changes in multi-dimensional models such as visualization models, data models, and mechanism models, and the process is relatively complicated. Therefore, how to quickly reconfigure the components of the digital twin workshop and integrate multi-dimensional models according to a unified specification when changes occur in the production workshop is a problem worthy of study. Summary of the invention

[0005] In order to solve the technical problems mentioned in the background technology, the present invention proposes a method for constructing and dynamically configuring a multi-dimensional and multi-level model of a digital twin workshop, which includes the following two steps:

[0006] S1: Construction of multi-dimensional and multi-level models of digital twin workshops;

[0007] S2: Multi-dimensional and multi-level model fusion of digital twin workshop.

[0008] Preferably, in step S1, the construction of the multi-dimensional and multi-level model of the digital twin workshop includes the following steps: manufacturing system relationship definition, digital twin workshop multi-dimensional and multi-level model definition, element level visualization model definition, production unit visualization model definition, formal definition of the production workshop visualization model, element level mechanism model definition, production unit mechanism model definition, formal definition of the production workshop mechanism model, digital twin workshop information model at the element level information model definition, digital twin workshop information model at the unit level information model definition, and digital twin workshop information model at the workshop level information model definition.

[0009] Preferably, the manufacturing system relationship is defined as follows:

[0010] System Structure=<SC,LPN>

[0011] In the formula: System Structure represents the manufacturing system relationship; SC represents the service unit; LPN represents the logistics path network;

[0012] The multi-dimensional and multi-level model of the digital twin workshop is defined as:

[0013] TwinModel={VisualModel,PrinModel,InfoModel};

[0014] Among them: TwinModel represents the multi-dimensional and multi-level model of the digital twin workshop; VisualModel represents the visualization model, which is a visualization display of the multi-dimensional and multi-level model of the digital twin workshop; PrinModel represents the mechanism model, which expresses the production operation logic and mechanism of the production workshop; InfoModel represents the information model, which integrates the production workshop operation data.

[0015] Preferably, at the equipment level, the multi-dimensional and multi-level model of the digital twin workshop is divided into three levels. At the equipment level, the data model, visualization model and mechanism model of the equipment form the basic model elements of the three dimensions; at the unit level, by describing the relationship between each device in the production unit, the multi-dimensional models of multiple devices are combined through the logical relationship within the unit to form a multi-dimensional model of the unit; at the workshop level, the production logic is formed through the product process route and the workshop logistics relationship, the logistics equipment between units is organically linked, and their multi-dimensional models are connected to form a multi-dimensional model of the workshop;

[0016] The element-level visualization model is defined as:

[0017] CompVisualModel={MotionModel,3DModel}

[0018] Among them: CompVisualModel represents the visual model of the element, MotionModel represents the element motion model, and defines the hierarchy and motion relationship of the equipment component model; 3DModel represents the 3D model of each component of the equipment;

[0019] The combination of the visualization models of each element forms the visualization model of the production unit, which is defined as:

[0020] SCVisualModel={CompVisualModel1,...,CompVisualModel i}

[0021] Where: SCVisualModel represents the unit-level visualization model, CompVisualModel1 represents the visualization model of an element in the production unit, and the visualization model of the production unit is composed of the visualization models of several elements;

[0022] The production units are associated with each other through logistics paths to form a visualization model of the production workshop. Therefore, the production workshop consists of production units and logistics equipment between production units. The formal definition of the visualization model of the production workshop is as follows:

[0023] ShopVisualModel={SCVisualModel i ,CompVisualModel j |1≤i≤n,1≤j≤m}

[0024] Where: ShopVisualModel represents the visual model of the production workshop, SCVisualModel i CompVisualModel represents the collection of all production unit visualization models in the workshop. j Represents the set of visualization models of all workshop production resources in the workshop; n is the number of units defined in the production workshop, and m is the number of elements that perform inter-unit logistics tasks in the production workshop;

[0025] The digital twin workshop mechanism model is uniformly represented at the element level through a seven-element model. Each element is an independent object that plays a specific role in the workshop. They encapsulate the internal operation logic and the interface for interaction with the external environment. The element-level mechanism model is defined as:

[0026] CompPrinModel={CompStateModel,CompLogicModel}

[0027] Where: CompPrinModel represents the mechanism model of the production equipment, CompStateModel represents the state model of the production equipment, and CompLogicModel represents the operation logic model of the production equipment;

[0028] The digital twin workshop mechanism model is the unit control logic for loading and unloading materials after the materials arrive at the unit. The production unit mechanism model is defined as:

[0029] SCPrinModel={SCStateModel,SCLogicModel}

[0030] Where: SCPrinModel represents the production unit mechanism model, SCStateModel represents the unit operation state, and SCLogicModel represents the operation logic of the production unit;

[0031] The operating status of the production unit is an organic combination of the element status. The operating status of the production unit and its corresponding parameters are defined as follows:

[0032]

[0033] The permission / prohibition of the production unit input depends on whether the unit can accept new materials into the buffer or directly process them, and the permission / prohibition of the output depends on whether the unit can accept existing materials leaving the unit;

[0034] The production workshop mechanism model is formally defined as:

[0035] ShopPrinModel={ShopStateModel,ShopLogicModel}

[0036] Where: ShopPrinModel represents the production workshop mechanism model, ShopStateModel is the workshop state model, which represents the different states of workshop operation, including idle, in production, and shutdown due to failure; ShopLogicModel is the logic model of the workshop, which includes the production logic model and the logistics network model;

[0037] The digital twin workshop information model includes real-time operation data and simulation execution data of production equipment at the element level; unit task sequence, real-time material data, and processing data at the unit level; and workshop production layout, scheduling plan, and operation data at the workshop level.

[0038] The digital twin workshop information model is defined at the element level as:

[0039] CompInfoModel={CompSimInfo,CompRealInfo,CompHistoryInfo}

[0040] Where: CompInfoModel represents the information model of the element, CompSimInfo is the simulation data of the element, including input data and output data; CompRealInfo is the real-time data of the element, which is obtained by classifying and storing the relevant data after collecting them through the SCADA system; CompHistoryInfo is the historical data;

[0041] The digital twin workshop information model is defined at the unit level as:

[0042] SCInfoModel={SCSimInfo,SCRealInfo,SCHistoryInfo}

[0043] In the formula: SCInfoModel represents the unit information model, SCSimInfo is the simulation data of the unit, including input data and output data; SCRealInfo is the real-time data of the unit; SCHistoryInfo is the historical data, which is composed of the simulation data and real-time data stored;

[0044] The digital twin workshop information model is defined as follows at the workshop level:

[0045] ShopInfoModel={ShopSimInfo, ShopRealInfo, ShopHistoryInfo}

[0046] In the formula: ShopInfoModel represents the shop information model, ShopSimInfo is the simulation data of the shop, including input data and output data, ShopRealInfo is the real-time data of the shop; the historical data ShopHistoryInfo is composed of the simulation data and real-time data stored.

[0047] Preferably, the multi-dimensional and multi-level fusion model comprises the following steps S21-S23:

[0048] S21: Model fusion for pre-execution simulation verification;

[0049] S22: Model fusion for real-time monitoring during execution;

[0050] S23: Model fusion towards post-execution optimization iterations.

[0051] Preferably, step S21 includes the following steps S211-S215:

[0052] In step S211, a production element object is constructed;

[0053] In step S212, a device visualization model is constructed, including construction of a device motion model and importing of component 3D models;

[0054] In step S213, according to the characteristics of the production elements, the mechanism models of the processor, actuator and buffer are defined, including simulation logic such as door opening and closing actions, triggering mechanisms, and action sequences; and simulation data are defined according to the equipment type;

[0055] In step S214, a production unit is formed by performing unit layout based on the existing production elements. The unit integrates the visualization model of the internal production elements and forms a unit mechanism model by configuring unit parameters.

[0056] In step S215, the workshop visualization and mechanism model is formed by configuring the logistics paths and logistics equipment between units, and the workshop simulation input is defined, including production scheduling and start and stop time, to form a workshop simulation information model.

[0057] Preferably, step S22 includes the following steps S221-S223:

[0058] In step S221, for the production element, its virtual monitoring point is configured, and the monitoring point name, element name, component name, physical quantity, data type, data unit, state attribute, key attribute, and sampling frequency are defined; and based on the object connection and embedding technology for process control and the interconnection communication protocol of numerical control equipment, real-time data is obtained from the physical workshop and written into the corresponding monitoring point to form the real-time information of the production element and improve the information model of the production element;

[0059] In step S222, at the production unit level, the element real-time information is extracted to form the required key information, the key information at least includes the processor status monitoring point and the buffer cache quantity, and the key information is mapped many-to-one to form the unit status information, and the key information and the status information together constitute the real-time information of the production unit;

[0060] In step S223, at the workshop level, the workshop production task information is obtained through the manufacturing execution system, and the production task execution progress is matched based on the production unit status to form real-time information of the production workshop.

[0061] Preferably, step S23 includes the following steps S231-S232:

[0062] In step S231, based on the existing model foundation of S21 and S22, the existing production plan is evaluated; based on the evaluation results, layout optimization and scheduling optimization are performed, the workshop is rearranged or rescheduled to form a new workshop multidimensional model, and the optimization plan is simulated and evaluated. When the optimization plan is feasible, it is sent to the production workshop to guide the optimization iteration of the physical workshop and update the workshop model;

[0063] In step S232, the multi-dimensional and multi-level model of the digital twin workshop is reconfigured and dynamically updated; when the digital twin workshop project is recreated or the workshop is changed, the corresponding multi-dimensional and multi-level model of the digital twin workshop needs to be newly created or updated in time;

[0064] The model building process includes steps S2321-S2322;

[0065] In step S2321, when new equipment is added or changed in the workshop, the system resource library is searched to determine whether there is such equipment. If there is equipment, the drag layout is performed based on such equipment; if there is no such equipment, the equipment modeling system is used to package and store such equipment, complete the geometric modeling of the workshop resources, and together with the changed model relationship, a workshop reconfiguration model based on the service unit and logistics path network model is constructed to generate a DTS visualization model;

[0066] Step S2322 includes steps S23221-S23224;

[0067] In S23221, the model relationships are changed and mapped to the visual model to implement logistics modeling;

[0068] In S23222, change the model simulation properties, including equipment movement speed and capacity;

[0069] In S23223, the process route of the workpiece is changed to form the input information of the workshop operation, and together with the simulation model and the logistics reconfiguration model, a representation model for system simulation is formed to complete the regeneration of the simulation model;

[0070] In step S23224, the data modeling is adjusted to check whether the digital twin workshop has implemented this type of communication protocol. If there is no such communication protocol, the data communication protocol interface is developed based on the abstract communication base class and extended to the data adaptation class. If there is such a protocol, the protocol is adapted to the virtual sensor, and the real-time data mapping is completed based on the virtual sensor, and the data model of this type of equipment is regenerated.

[0071] The beneficial technical effects of the present invention are:

[0072] 1. The present invention adopts a workshop modeling method based on production units, decomposes a complex production workshop into three levels, and reflects the multi-dimensional characteristics of the digital twin workshop model by performing multi-dimensional modeling on the equipment. The multi-level characteristics of the digital twin workshop model are reflected by constructing corresponding models of the workshop at the three levels of elements, units, and workshops. A clear and unambiguous method for constructing multi-dimensional and multi-level models of digital twin workshops is established. When digital twin modeling of the workshop is performed, hierarchical division can be performed in the face of the problems of complex workshop structure, massive multi-source data, and heterogeneous operating mechanisms. Targeted model definition is performed at each level for the common characteristics of the level, and integration of different models and data is achieved through the association configuration between different levels.

[0073] 2. Based on the proposed digital twin workshop model construction method, the present invention defines the digital twin workshop model as three dimensions of "mechanism-visualization-information". Among the three levels, the mechanism model describes the operation mechanism and component movement logic of the equipment or other elements at the element level, describes the production organization logic between several elements in the unit at the unit level, such as the order of loading and unloading buffers, etc., and forms the workshop production operation mechanism at the workshop level, such as the association relationship and logistics structure between the units; the visualization model realizes the mapping of the association and movement relationship of the components through topology at the element level, and associates the three-dimensional model of the components with the topological node to realize the movement visualization modeling of the equipment. The visualization model relies on the unit and workshop operation structure in the mechanism model to associate the equipment model at the unit level and workshop level to realize the visualization modeling of the unit and workshop; the information model constructs the virtual-real connection between the model and the physical entity at the element level and describes the real-time operation data of the workshop elements, describes the operation statistics and unit status information of the equipment in the unit at the unit level, and further describes the production tasks and execution information during the operation of the workshop at the workshop level. The above models meet the application requirements of virtual workshop construction, workshop simulation operation, virtual-reality connection, and virtual-reality synchronization in the implementation process of digital twin workshops from three aspects.

[0074] 3. The present invention adopts a configuration / reconfiguration method to realize the construction process of a multi-dimensional and multi-level model of a digital twin workshop, decomposes "data-visualization-mechanism" into various configuration steps, and describes the relationship between the steps. In the process of implementing the proposed digital twin model construction framework and various dimensional models, the parameters and features of the model are continuously changed in the form of configuration to achieve sub-real-time update of the workshop model, which is the first time the workshop model is built and the model needs to be updated when the workshop changes. This forms a digital twin model that evolves dynamically according to the changes in the workshop, and provides a clear solution and configuration modeling route for the digital twin workshop model facing changes in the workshop. BRIEF DESCRIPTION OF THE DRAWINGS

[0075] Figure 1 Schematic diagram of the framework for building a multi-dimensional and multi-level model of a digital twin workshop;

[0076] Figure 2 Schematic diagram of the multi-dimensional and multi-level model construction and dynamic configuration process of the digital twin workshop. DETAILED DESCRIPTION

[0077] To make the implementation purpose, technical solution and advantages of the present invention clearer, the technical solution in the embodiments of the present invention will be described clearly and completely in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them.

[0078] Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the invention claimed for protection, but merely represents some embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0079] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features and technical solutions in the embodiments may be combined with each other.

[0080] A method for constructing and dynamically configuring a multi-dimensional and multi-level model of a digital twin workshop of the present invention comprises the following two steps:

[0081] S1: Construction of multi-dimensional and multi-level models of digital twin workshops;

[0082] S2: Multi-dimensional and multi-level model fusion of digital twin workshop.

[0083] Preferably, in step S1, the construction of the multi-dimensional and multi-level model of the digital twin workshop includes the following steps: manufacturing system relationship definition, multi-dimensional and multi-level model definition of the digital twin workshop, element-level visualization model definition, production unit visualization model definition, formal definition of the production workshop visualization model, element-level mechanism model definition, production unit mechanism model definition, formal definition of the production workshop mechanism model, digital twin workshop information model at the element-level information model definition, digital twin workshop information model at the unit-level information model definition, digital twin workshop information model at the workshop-level information model definition. Preferably, the multi-dimensional and multi-level model of the digital twin workshop includes three dimensions: information model, visualization model and mechanism model, and is expanded to three levels: workshop level, unit level and element level in terms of model construction level, as shown in the attached figure. Figure 1 As shown. In order to uniformly express heterogeneous discrete manufacturing systems, a series of graphical formal model expression methods and concepts have been proposed in the prior art. Among them, the seven-element model is proposed to characterize the basic components of the system, the service unit model and the logistics path network model are proposed to characterize the production and logistics organizational relationships respectively, and the workshop is a collection of equipment, personnel, workpieces, environment and other elements in the same physical space. In the following, "<>" represents the composition and characteristics of a mechanism model.

[0084] The seven-factor model is defined as:

[0085] Seven Elements=<C,P,E,B,F,L,VSN>

[0086] In the formula: Seven Elements is the seven elements, which is a unified expression of people, machines, materials, methods and environment in the workshop. C represents the controller, which is the mapping of various control systems / equipment or decision-makers, and provides decision-making services for the system. P represents the processor, which is the mapping of various processing equipment, and provides operation-related services for workpieces driven by production tasks. E represents the actuator, which is the mapping of various logistics equipment, and provides material transfer services for workpieces based on logistics scheduling rules driven by logistics tasks. B represents the buffer, which is the mapping of various buffers and storage equipment, and provides temporary or long-term storage services for workpieces. F represents the flow entity, that is, the workpiece, including the mapping of blanks, semi-finished products and products, etc., which accepts the services of processors, actuators and buffers. L represents the logistics path, which is the mapping of logistics relations. VSN represents the virtual service node, which is a high-level summary and abstraction of production organization relations, logistics relations and production logic.

[0087] Furthermore, the present invention defines the manufacturing system relationship based on the seven-element model as follows:

[0088] System Structure=<SC,LPN>

[0089] In the formula: System Structure represents the manufacturing system relationship, which is the composition form of each element within the system. SC represents the service unit, which is a set of seven elements or its subset with specific service functions. LPN represents the logistics path network, which is a mapping of the actual logistics layout and relationship.

[0090] Preferably, the multi-dimensional and multi-level model of the digital twin workshop is defined as:

[0091] TwinModel={VisualModel,PrinModel,InfoModel}.

[0092] Among them: TwinModel represents the multi-dimensional and multi-level model of the digital twin workshop; VisualModel represents the visualization model, which is a visual display of the multi-dimensional and multi-level model of the digital twin workshop; PrinModel represents the mechanism model, which expresses the production operation logic and mechanism of the production workshop and is the basis for the operation of the virtual workshop; InfoModel represents the information model, which integrates the production workshop operation data.

[0093] Preferably, at the equipment level, the multi-dimensional and multi-level model of the digital twin workshop is divided into three levels. At the equipment level, the data model, visualization model and mechanism model of the equipment form the basic model elements of the three dimensions; at the unit level, by describing the relationship between each device in the production unit, the multi-dimensional models of multiple devices are combined through the logical relationship within the unit to form a multi-dimensional model of the unit; at the workshop level, the production logic is formed through the product process route and the workshop logistics relationship, the logistics equipment between units is organically linked, and their multi-dimensional models are connected to form a multi-dimensional model of the workshop.

[0094] The multi-dimensional and multi-level model of the digital twin workshop proposed in the present invention includes three dimensions: information model, visualization model and mechanism model, and is expanded to three levels: workshop level, unit level and equipment level (element level) in terms of model construction level. Compared with the multi-dimensional virtual model including data model, geometric model and logical model in the prior art, it has the following advantages:

[0095] In terms of model definition, the data model and the logic model are expanded, and the data model is included in the information model. It is not just a conceptual expansion. When realizing the virtual-real connection of the digital twin workshop, the adaptation problem of the heterogeneous protocol is solved by encapsulating the heterogeneous data communication protocol, and the simulation data is integrated through the simulation model to solve the confusion between the actual operation data of the physical equipment. Similarly, in terms of the mechanism model, the construction of the operation logic model of the workshop, unit and element as the main content of the mechanism model construction is a necessary condition for realizing the virtual-real connection of the workshop, unit and element in the digital twin workshop through simulation; in addition, the variable characteristics of the equipment during operation and the probability events of the equipment during operation can also be uniformly encapsulated as a kind of mechanism model. After constructing the information model and the mechanism model, compared with the original visualization model, on the one hand, the detailed hierarchical visualization model definition of the new visualization model provides a clearer idea for the construction of the visualization model of the digital twin workshop, and on the other hand, it can also realize more data in the operation process of the digital twin workshop. Visual display and auxiliary decision-making applications, such as alarms, predictions, etc., these contents need to be combined with artificial intelligence algorithms and real-time data-driven simulations, which do not belong to the scope of the present invention.

[0096] Preferably, in the multi-dimensional and multi-level model of the digital twin workshop, the three visualization models of element level, unit level and workshop level are the appearance representations of physical workshop objects, mainly focusing on external information such as the geometric properties and motion properties of the physical objects.

[0097] Preferably, the element-level visualization model is defined as:

[0098] CompVisualModel={MotionModel,3DModel}

[0099] Among them: CompVisualModel represents the visualization model of the element, MotionModel represents the element motion model, which defines the hierarchy and motion relationship of the equipment component models; 3DModel represents the 3D models of each component of the equipment, including geometric information such as model vertices and faces, and appearance information such as model textures and materials.

[0100] Elements include production equipment and materials. Among them, the material itself does not contain motion attributes, the material's motion model MotionModel is empty, and only the 3D model 3Dmodel exists.

[0101] Preferably, the combination of the visualization models of the various elements forms a visualization model of the production unit, and the visualization model of the production unit is defined as:

[0102] SCVisualModel={CompVisualModel1,...,CompVisualModel i}

[0103] Wherein: SCVisualModel represents the unit-level visualization model, CompVisualModel1 represents the visualization model of an element in the production unit, and the visualization model of the production unit is composed of the visualization models of several elements.

[0104] Preferably, the production units are associated with each other through logistics paths to form a visualization model of the production workshop. Therefore, the production workshop is composed of production units and logistics equipment between production units. The formal definition of the visualization model of the production workshop is as follows:

[0105] ShopVisualModel={SCVisualModel i ,CompVisualModel j |1≤i≤n,1≤j≤m}

[0106] Where: ShopVisualModel represents the visual model of the production workshop, SCVisualModel i CompVisualModel represents the collection of all production unit visualization models in the workshop. j It represents the set of visualization models of all workshop production resources in the workshop. n is the number of units defined in the production workshop, and m is the number of elements that perform inter-unit logistics tasks in the production workshop. It should be noted that the elements that perform inter-unit logistics tasks, such as AGV and overhead crane, do not belong to any unit, so they are identified as inter-unit logistics elements of the workshop. Other elements are included in the production unit and are uniformly packaged by the production unit.

[0107] Compared with the existing technology, the multi-dimensional and multi-level visualization model of the digital twin workshop proposed in the present invention has the following advantages: by hierarchically defining the visualization models at the workshop level, unit level and element level, the definition of the original visualization model is expanded from equipment to units and workshops, and the unit-level visualization model is constructed through the construction and collection of equipment models, and can be visualized and operated through the drive of the mechanism model.

[0108] Preferably, the digital twin workshop mechanism model is an expression of the workshop operation mechanism.

[0109] Preferably, the digital twin workshop mechanism model at the element level includes movement processes such as machine tool door opening and closing logic and six-degree-of-freedom manipulator motion solution algorithm.

[0110] Preferably, the digital twin workshop mechanism model is uniformly characterized at the element level through a seven-element model. Each element is an independent object that plays a specific role in the workshop. They encapsulate the internal operation logic and the interface for interaction with the external environment. The element-level mechanism model is defined as:

[0111] CompPrinModel={CompStateModel,CompLogicModel}

[0112] Where: CompPrinModel represents the mechanism model of the production equipment, CompStateModel represents the state model of the production equipment, and CompLogicModel represents the operation logic model of the production equipment, which is the logic of the state change of the equipment after receiving external input. This logic is the basis for the operation of the controller control elements.

[0113] Preferably, the digital twin workshop mechanism model is the unit control logic for loading and unloading operations after the materials arrive at the unit at the unit level. The production unit mechanism model is defined as:

[0114] SCPrinModel={SCStateModel,SCLogicModel}

[0115] In the formula: SCPrinModel represents the production unit mechanism model, SCStateModel represents the unit operation state, and SCLogicModel represents the operation logic of the production unit.

[0116] Preferably, in a production unit, the processor P is a basic component, which provides workpiece processing services for the unit, such as processing, testing, disassembly and assembly, etc. The flow entity F enters the unit through the virtual service node, and then passes through the input buffer B in turn. in , processor P and output buffer B outReceive services and finally leave the unit through the virtual service node. Controller C controls the internal actuator E int To realize the flow of the flow entity F in the above elements. The above logic is defined as a template and encapsulated into the unit controller.

[0117] Preferably, the production unit operation state is an organic combination of element states, and the production unit operation state and its corresponding parameters are defined as follows:

[0118]

[0119] The permission / prohibition of the production unit input depends on whether the unit can accept new materials into the cache or directly process them, and the permission / prohibition of the output depends on whether the unit can accept existing materials leaving the unit.

[0120] Preferably, the digital twin workshop mechanism model is expressed as the workshop production process operation mechanism at the workshop level, including the production operation logic based on material process, production logistics scheduling method, etc. The production workshop mechanism model is formally defined as:

[0121] ShopPrinModel={ShopStateModel,ShopLogicModel}

[0122] In the formula: ShopPrinModel represents the production workshop mechanism model, ShopStateModel is the workshop state model, which represents the different states of workshop operation, including idle, in production, and shutdown due to failure, etc. ShopLogicModel is the logic model of the workshop, which includes the production logic model and the logistics network model. The logistics network structure in the workshop determines the basic framework of the logic model, and the process route of the workpiece determines the entity flow of the logic model.

[0123] Compared with the existing technology, the digital twin workshop mechanism model proposed in this invention has the following advantages:

[0124] First, according to the multi-level idea in the multi-dimensional and multi-level modeling method of the digital twin workshop, the operation mechanism and main operation logic of the physical objects at each level are described from the three levels of elements, units, and workshops. At the equipment level, by encapsulating the element mechanism model, it can be simulated according to the real physical elements such as the opening and closing actions of the machine tool when the element is virtually running, so as to realize the mechanism mapping at the element level. At the unit level, the operation mechanism of the unit is constructed through the logical relationship between the elements in the unit, including the material loading and unloading process of the production process, the equipment service sequence, etc., so that the virtual unit can form the virtual operation process of the unit through the equipment service sequence and then call the operation mechanism of the equipment in the process of simulating the operation of the physical unit, so as to realize the mechanism mapping at the unit level. At the workshop level, the logistics structure and logistics relationship between units are further associated, and the workshop production logic is formed through the workpiece process route. During the simulation operation, the mechanism mapping of the production workshop is realized by calling the unit mechanism model and the operation model of the logistics equipment between units. The above mechanism model combined with the visualization model can realize the visualization simulation and virtual-real mapping of the virtual workshop.

[0125] Preferably, the digital twin workshop information model stores the actual operation data and virtual simulation data of the elements / systems, and serves as a bridge connecting the digital twin workshop and the physical workshop.

[0126] Preferably, the digital twin workshop information model includes real-time operation data and simulation execution data (operating time, waiting time, congestion time, etc.) of production equipment at the element level; unit task sequence, real-time material data, and processing process data at the unit level; and workshop production layout, scheduling plan, and operation data at the workshop level.

[0127] Preferably, the digital twin workshop information model is defined as follows at the element level:

[0128] CompInfoModel={CompSimInfo,CompRealInfo,CompHistoryInfo}

[0129] Where: CompInfoModel represents the information model of the element, CompSimInfo is the simulation data of the element, including input data (such as the planned time for the equipment to execute the task) and output data (such as the actual execution time of the equipment); CompRealInfo is the real-time data of the element, which is obtained by collecting relevant data through systems such as SCADA and then classifying and storing these data, such as the real-time motion data of each axis of the machine tool, the state of the door opening and closing, etc.; CompHistoryInfo is the historical data, which is composed of real-time data and simulation data after execution, and is the basis for retrospective analysis.

[0130] Preferably, the digital twin workshop information model is defined as follows at the unit level:

[0131] SCInfoModel={SCSimInfo,SCRealInfo,SCHistoryInfo}

[0132] In the formula: SCInfoModel represents the unit information model, SCSimInfo is the simulation data of the unit, including input data (such as production tasks) and output data (such as production instructions); SCRealInfo is the real-time data of the unit, such as machine tool status, key component operation parameters, etc., which is the collection and simplification of element real-time data. SCHistoryInfo is historical data, which is composed of simulation data and real-time data after storage.

[0133] Preferably, the digital twin workshop information model is defined as follows at the workshop level:

[0134] ShopInfoModel={ShopSimInfo, ShopRealInfo, ShopHistoryInfo}

[0135] In the formula: ShopInfoModel represents the shop information model, ShopSimInfo is the shop simulation data, including input data (such as production scheduling) and output data (such as production simulation evaluation indicators), ShopRealInfo is the shop real-time data, which is a further integration of unit and element data, including production instructions and execution feedback messages. Similarly, the historical data ShopHistoryInfo is composed of simulation data and real-time data after storage.

[0136] After constructing the sub-models related to the multi-dimensional and multi-level model of the digital twin workshop, these sub-models need to be fused to form a multi-dimensional and multi-level fusion model of the digital twin workshop. Depending on the application scenario of the model, the fusion of sub-models also has different focuses. The application scenarios of the digital twin workshop can be divided into pre-execution simulation verification, real-time monitoring during execution, and post-execution optimization iteration according to the workshop operation stage.

[0137] Compared with the existing technology, the digital twin workshop information model proposed in this invention has the following advantages:

[0138] At the element level, data from different sources of elements are integrated. In the process of virtual-real mapping of equipment in the digital twin workshop, simulation data, real-time operation data and historical data of the equipment are constructed respectively. These data can be provided on demand according to different digital twin application requirements, and different data analysis services are launched for different applications. At the unit level, through the high abstraction of all data of internal elements, the element status data and real-time operation data of the production unit are formed. Through the mapping of element status data and real-time operation data in the unit, the specific execution of production execution tasks (such as loading and unloading, caching, etc.) involving multiple element interactions can be effectively perceived, providing data support for precise control of the production site. At the workshop level, the main concern is the demand for workshop macro production data, including workshop production tasks, completion status, etc. These data are further provided by units and elements, realizing the integration and perception of workshop operation process data. In addition, the workshop structure information and historical version information are also uniformly encapsulated, forming the data basis for model evolution in the proposed digital twin workshop multi-dimensional and multi-level model construction method.

[0139] Preferably, the multi-dimensional and multi-level fusion model comprises the following steps S21-S23:

[0140] S21: Model fusion for pre-execution simulation verification;

[0141] S22: Model fusion for real-time monitoring during execution;

[0142] S23: Model fusion towards post-execution optimization iterations.

[0143] Preferably, step S21 is for model fusion of pre-execution simulation verification to quickly build a virtual workshop and verify the pros and cons of production scheduling and workshop layout solutions. Specifically, the following steps S211-S215 are included:

[0144] Preferably, a production element object is constructed in step S211.

[0145] Preferably, in step S212, a device visualization model is constructed, including construction of a device motion model and importing of component 3D models.

[0146] Preferably, in step S213, according to the characteristics of the production elements, the mechanism models of the processor, actuator and buffer are defined, including simulation logic such as door opening and closing actions, triggering mechanisms, action sequences, etc. The simulation data is defined according to the equipment type, such as defining the simulation production instructions and simulation execution parameters for the processing equipment.

[0147] Preferably, in step S214, a production unit is formed by performing unit layout based on existing production elements. The unit integrates a visualization model of internal production elements and forms a unit mechanism model by configuring unit parameters. The unit parameters include buffer logic, loading and unloading positions, etc.

[0148] Preferably, in step S215, a workshop visualization and mechanism model is formed by configuring the logistics paths and logistics equipment between units, and a workshop simulation input is defined, including information such as production scheduling and start and stop time, to form a workshop simulation information model.

[0149] Preferably, step S22 is for the model fusion of real-time monitoring during execution, which is used to monitor the physical workshop in real time and find production anomalies in time. Specifically, the following steps S221-S223 are included:

[0150] Preferably, in step S221, the virtual monitoring point is configured for the production element, and the monitoring point name, element name, component name, physical quantity, data type, data unit, state attribute, key attribute, sampling frequency and other information are defined. Based on the object connection and embedding technology for process control and the communication protocol such as the interconnection of numerical control equipment, real-time data is obtained from the physical workshop and written into the corresponding monitoring point to form the real-time information of the production element and improve the information model of the production element.

[0151] Preferably, in step S222, at the production unit layer, the element real-time information is extracted to form the required key information, which includes at least the processor status monitoring point and the buffer cache quantity, and the key information is mapped many-to-one to form unit status information. These key information and status information together constitute the real-time information of the production unit.

[0152] Preferably, in step S223, at the workshop level, the workshop production task information is obtained through the manufacturing execution system, and the production task execution progress is matched based on the production unit status to form real-time information of the production workshop.

[0153] Preferably, step S23 is for the model fusion of the post-execution optimization iteration to optimize the workshop after execution and verify the feasibility of the optimization scheme through simulation. Specifically, the following steps S231-S232 are included:

[0154] Preferably, in step S231, the existing production plan is evaluated based on the existing model foundation of S21 and S22. Then, layout optimization and scheduling optimization are performed based on the evaluation results, and the workshop is rearranged or rescheduled to form a new workshop multidimensional model. The optimization plan is simulated and evaluated. When the optimization plan is feasible, it is sent to the production workshop to guide the optimization iteration of the physical workshop and update the workshop model. The evaluation method in the prior art can be used to evaluate the existing production plan.

[0155] Preferably, in step S232, the multi-dimensional and multi-level model of the digital twin workshop is reconfigured and dynamically updated. After the digital twin workshop project is recreated, or the workshop changes (such as purchasing new equipment for workshop transformation), it is necessary to create or timely update the corresponding multi-dimensional and multi-level model of the digital twin workshop. The present invention decomposes the model building process into steps S2321-S2322.

[0156] Preferably, in step S2321, when new equipment is added or changed in the workshop, the system resource library is searched to determine whether there is such equipment. If there is equipment, the drag layout is performed based on such equipment. If there is no such equipment, the equipment modeling system is used to package and store such equipment, complete the geometric modeling of the workshop resources, and together with the changed model relationship, a workshop reconfiguration model based on the service unit and logistics path network model is formed to generate a DTS visualization model.

[0157] Preferably, in step S2322, the mechanism model is adjusted, and the mechanism of the system needs to be updated after the system is changed, mainly various simulation parameters. Step S2322 includes S23221-S23224.

[0158] Preferably, in S23221, the model relationship is changed and the model relationship is mapped into the visualization model to realize logistics modeling.

[0159] Preferably, in S23222, the model simulation properties are changed, including the equipment moving speed, capacity, etc.

[0160] Preferably, in S23223, the process route of the workpiece is changed to form input information for workshop operation, and together with the simulation model and the logistics reconfiguration model, a representation model for system simulation is formed to complete the regeneration of the simulation model.

[0161] Preferably, in step S23224, the data modeling is adjusted to check whether the digital twin workshop implements the communication protocol of this type. If there is no such communication protocol, the data communication protocol interface is developed based on the abstract communication base class and extended to the data adaptation class. If there is such a protocol, the protocol is adapted to the virtual sensor, and the real-time data mapping is completed based on the virtual sensor, and the data model of this type of equipment is regenerated.

[0162] Preferably, the fusion and connection of the mechanism model, the visualization model and the information model together constitute a multi-dimensional fusion model of the virtual workshop for the digital twin workshop.

[0163] The multi-dimensional and multi-level model configuration and dynamic update method of the digital twin workshop proposed in the present invention has the following advantages:

[0164] The process of building a multi-dimensional and multi-level model of a digital twin workshop is decomposed into detailed configuration steps at different dimensions and levels. When a workshop changes, the multi-dimensional and multi-level model of the digital twin workshop can be updated based on the corresponding configuration steps for the changed items. This helps to update the digital twin model faster and more conveniently without rebuilding other corresponding models, simplifies the model update steps, and improves the efficiency of building a multi-dimensional and multi-level model of a digital twin workshop.

[0165] The above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention. Although the present invention has been described in detail with reference to the above embodiments, the present invention is not limited to the above specific implementation methods. Therefore, any modification or equivalent replacement of the present invention; and all technical solutions and improvements thereof that do not depart from the spirit and scope of the invention are included in the scope of the claims of the present invention.

Claims

1. A method for constructing and dynamically configuring a multi-dimensional and multi-level model of a digital twin workshop, characterized in that: It includes the following two steps: S1: Construction of multi-dimensional and multi-level models of digital twin workshops; S2: Multi-dimensional and multi-level model fusion of digital twin workshop; In step S1, the construction of the multi-dimensional and multi-level model of the digital twin workshop includes the following steps: manufacturing system relationship definition, digital twin workshop multi-dimensional and multi-level model definition, element level visualization model definition, production unit visualization model definition, formal definition of production workshop visualization model, element level mechanism model definition, production unit mechanism model definition, production workshop mechanism model formal definition, digital twin workshop information model at element level information model definition, digital twin workshop information model at unit level information model definition, digital twin workshop information model at workshop level information model definition; The manufacturing system relationships are defined as follows: System Structure=<SC,LPN> In the formula: System Structure represents the manufacturing system relationship; SC represents the service unit; LPN represents the logistics path network; The multi-dimensional and multi-level model of the digital twin workshop is defined as: TwinModel={VisualModel,PrinModel,InfoModel}; Among them: TwinModel represents the multi-dimensional and multi-level model of the digital twin workshop; VisualModel represents the visualization model, which is the visualization display of the multi-dimensional and multi-level model of the digital twin workshop; PrinModel represents the mechanism model, which expresses the production operation logic and mechanism of the production workshop; InfoModel represents the information model, which integrates the operation data of the production workshop; The multi-dimensional and multi-level fusion model includes the following steps S21-S23: S21: Model fusion for pre-execution simulation verification; S22: Model fusion for real-time monitoring during execution; S23: Model fusion towards post-execution optimization iterations.

2. A method for constructing and dynamically configuring a multi-dimensional and multi-level model of a digital twin workshop according to claim 1, characterized in that: At the equipment level, the multi-dimensional and multi-level model of the digital twin workshop is divided into three levels. At the equipment level, the data model, visualization model and mechanism model of the equipment form the basic model elements of the three dimensions; at the unit level, by describing the relationship between each device in the production unit, the multi-dimensional models of multiple devices are combined through the logical relationship within the unit to form a multi-dimensional model of the unit; At the workshop level, the production logic is formed through the product process route and the workshop logistics relationship, the logistics equipment between units are organically linked, and their multi-dimensional models are connected to form a multi-dimensional model of the workshop; The element-level visualization model is defined as: CompVisualModel={MotionModel,3DModel} Among them: CompVisualModel represents the visual model of the element, MotionModel represents the element motion model, and defines the hierarchy and motion relationship of the equipment component model; 3DModel represents the 3D model of each component of the equipment; The combination of the visualization models of each element forms the visualization model of the production unit, which is defined as: SCVisualModel={CompVisualModel1,...,CompVisualModel i } Where: SCVisualModel represents the unit-level visualization model, CompVisualModel1 represents the visualization model of an element in the production unit, and the visualization model of the production unit is composed of the visualization models of several elements; The production units are associated with each other through logistics paths to form a visualization model of the production workshop. Therefore, the production workshop consists of production units and logistics equipment between production units. The formal definition of the visualization model of the production workshop is as follows: ShopVisualModel={SCVisualModel i ,CompVisualModel j |1≤i≤n,1≤j≤m} Where: ShopVisualModel represents the visual model of the production workshop, SCVisualModel i CompVisualModel represents the collection of all production unit visualization models in the workshop. j Represents the set of visualization models of all workshop production resources in the workshop; n is the number of units defined in the production workshop, and m is the number of elements that perform inter-unit logistics tasks in the production workshop; The digital twin workshop mechanism model is uniformly represented at the element level through a seven-element model. Each element is an independent object that plays a specific role in the workshop. They encapsulate the internal operation logic and the interface for interaction with the external environment. The element-level mechanism model is defined as: CompPrinModel={CompStateModel,CompLogicModel} Where: CompPrinModel represents the mechanism model of the production equipment, CompStateModel represents the state model of the production equipment, and CompLogicModel represents the operation logic model of the production equipment; The digital twin workshop mechanism model is the unit control logic for loading and unloading materials after the materials arrive at the unit. The production unit mechanism model is defined as: SCPrinModel={SCStateModel,SCLogicModel} Where: SCPrinModel represents the production unit mechanism model, SCStateModel represents the unit operation state, and SCLogicModel represents the operation logic of the production unit; The operating status of the production unit is an organic combination of the element status. The operating status of the production unit and its corresponding parameters are defined as follows: The permission / prohibition of the production unit input depends on whether the unit can accept new materials into the buffer or directly process them, and the permission / prohibition of the output depends on whether the unit can accept existing materials leaving the unit; The production workshop mechanism model is formally defined as: ShopPrinModel={ShopStateModel,ShopLogicModel} Where: ShopPrinModel represents the production workshop mechanism model, ShopStateModel is the workshop state model, which represents the different states of workshop operation, including idle, in production, and failure shutdown; ShopLogicModel is the logic model of the workshop, which includes the production logic model and the logistics network model; The digital twin workshop information model includes real-time operation data and simulation execution data of production equipment at the element level; unit task sequence, real-time material data, and processing data at the unit level; and workshop production layout, scheduling plan, and operation data at the workshop level. The digital twin workshop information model is defined at the element level as: CompInfoModel={CompSimInfo,CompRealInfo,CompHistoryInfo} Where: CompInfoModel represents the information model of the element, CompSimInfo is the simulation data of the element, including input data and output data; CompRealInfo is the real-time data of the element, which is obtained by classifying and storing the relevant data after collecting them through the SCADA system; CompHistoryInfo is the historical data; The digital twin workshop information model is defined at the unit level as: SCInfoModel={SCSimInfo,SCRealInfo,SCHistoryInfo} In the formula: SCInfoModel represents the unit information model, SCSimInfo is the simulation data of the unit, including input data and output data; SCRealInfo is the real-time data of the unit; SCHistoryInfo is the historical data, which is composed of simulation data and real-time data stored; The digital twin workshop information model is defined as follows at the workshop level: ShopInfoModel={ShopSimInfo, ShopRealInfo, ShopHistoryInfo} In the formula: ShopInfoModel represents the shop information model, ShopSimInfo is the simulation data of the shop, including input data and output data, ShopRealInfo is the real-time data of the shop; the historical data ShopHistoryInfo is composed of the simulation data and real-time data stored.

3. A method for constructing and dynamically configuring a multi-dimensional and multi-level model of a digital twin workshop according to claim 2, characterized in that: Step S21 The process comprises the following steps S211-S215: In step S211, a production element object is constructed; In step S212, a device visualization model is constructed, including construction of a device motion model and importing of component 3D models; In step S213, according to the characteristics of the production elements, the mechanism models of the processor, the actuator and the buffer are defined, including simulation logic such as the door opening and closing actions, the trigger mechanism and the action sequence; and the simulation data are defined according to the equipment type; In step S214, a production unit is formed by performing unit layout based on the existing production elements. The unit integrates the visualization model of the internal production elements and forms a unit mechanism model by configuring unit parameters. In step S215, the workshop visualization and mechanism model is formed by configuring the logistics paths and logistics equipment between units, and the workshop simulation input is defined, including production scheduling and start and stop time, to form a workshop simulation information model.

4. A method for constructing and dynamically configuring a multi-dimensional and multi-level model of a digital twin workshop according to claim 3, characterized in that: Step S22 The process comprises the following steps S221-S223: In step S221, for the production element, its virtual monitoring point is configured, and the monitoring point name, element name, component name, physical quantity, data type, data unit, state attribute, key attribute, and sampling frequency are defined; and based on the object connection and embedding technology for process control and the interconnection communication protocol of numerical control equipment, real-time data is obtained from the physical workshop and written into the corresponding monitoring point to form the real-time information of the production element and improve the information model of the production element; In step S222, at the production unit level, the element real-time information is extracted to form the required key information, the key information at least includes the processor status monitoring point and the buffer cache quantity, and the key information is mapped many-to-one to form the unit status information, and the key information and the status information together constitute the real-time information of the production unit; In step S223, at the workshop level, the workshop production task information is obtained through the manufacturing execution system, and the production task execution progress is matched based on the production unit status to form real-time information of the production workshop.

5. A method for constructing and dynamically configuring a multi-dimensional and multi-level model of a digital twin workshop according to claim 4, characterized in that: Step S23 The process comprises the following steps S231-S232: In step S231, based on the existing model foundation of S21 and S22, the existing production plan is evaluated; based on the evaluation results, layout optimization and scheduling optimization are performed, the workshop is rearranged or rescheduled to form a new workshop multidimensional model, and the optimization plan is simulated and evaluated. When the optimization plan is feasible, it is sent to the production workshop to guide the optimization iteration of the physical workshop and update the workshop model; In step S232, the multi-dimensional and multi-level model of the digital twin workshop is reconfigured and dynamically updated; when the digital twin workshop project is recreated or the workshop is changed, the corresponding multi-dimensional and multi-level model of the digital twin workshop needs to be newly created or updated in time; The model building process includes steps S2321-S2322; In step S2321, when a new device is added or changed in the workshop, the system resource library is searched to determine whether there is such a device. If there is a device, the layout is dragged and dropped based on the device; If there is no such equipment, the equipment modeling system will be used to package and store the equipment, complete the geometric modeling of the workshop resources, and together with the changed model relationship, form a workshop reconfiguration model based on the service unit and logistics path network model to generate a DTS visualization model; Step S2322 includes steps S23221-S23224; In S23221, the model relationships are changed and mapped to the visual model to implement logistics modeling; In S23222, change the model simulation properties, including equipment movement speed and capacity; In S23223, the process route of the workpiece is changed to form the input information of the workshop operation, and together with the simulation model and the logistics reconfiguration model, a representation model for system simulation is formed to complete the regeneration of the simulation model; In step S23224, the data modeling is adjusted to check whether the digital twin workshop has implemented this type of communication protocol. If there is no such communication protocol, the data communication protocol interface is developed based on the abstract communication base class and extended to the data adaptation class. If there is such a protocol, the protocol is adapted to the virtual sensor, and the real-time data mapping is completed based on the virtual sensor, and the data model of this type of equipment is regenerated.

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