## 3 Architecture of DT Workshop System
### Real-Time Mapping of Workshop Processes  
Multidimensional data fusion is the cornerstone of ensuring the reliability of virtual objects. The authenticity of the production process simulation relies on the comprehensive description of the actual environment. The multidimensional dynamic data is associated with physical entity properties via real-time mapping to support the operation of the service drive layer. Real-time mapping subjects are predominantly workpieces, equipment, workers, production environment, and production knowledge. At the physical entity side, multiple types of unstructured data (e.g., contracts, drawings, notifications, etc.), multi-device collection data, multi-resource structured forms, and existing systems (e.g., MES/ERP/WMS, etc.) are blended in each production stage, which standardization data based on association mapping algorithms is critical.  
The mapping logic utilizes tagging. The workpiece/intermediate product forms a set of virtual tags, including product size, processing information, work order information, processing worker information, and other collections based on their self-encoding. During the work execution, operation behavior information and state transfer data are recorded synchronously to provide a process traceability interface. According to the rules  
Figure 4: Jobs information and status transfer between DT and equipment.  
of operation behavior transfer, the real-time mapping of equipment is stored with each piece of equipment corresponding to an independent database, and the digital twin system enables the virtual processing process to be launched according to the data so as to monitor the production quality. Workshop operations-oriented environment-aware data take the form of setting sensitive parameter thresholds in the mapping process due to the excessive amount of data and only convert and store records of environmental change periods. The knowledge data are scattered in the existing systems of the enterprise, where interfaces are established with the digital twin system for labeling transformation and storage by process category.  
The real-time mapping process consists of three phases. Firstly, the initialization is completed, the corresponding interface is launched, the form information is verified, and the information on virtual workshop equipment, environment, and workers is adjusted to be consistent with the physical entity. Subsequently, the real-time mapping operates, and the background activates data mapping transmission monitoring to promptly adjust and make up the data for the interfaces with package loss. Finally, completing the data handling and the massive production data are used as the input of the service drive layer and application service layer to support production decision-making, scheduling optimization, abnormality warning, etc., which are specifically researched in Sections 4 and 5. The schematic diagram of the real-time mapping of workshop operations is shown in Figure 5.  
The manufacturing execution behavior transfer rules and the workshop process real-time mapping are the fundamental operations in the DT system development, which are indispensable links to support the simulation operation and provide feasibility guarantees for the introduction of subsequent mathematical models and the application of decision support methods.