Result: Object-oriented modeling mechanism for digital twin workshop elements.

• Proposes a five-layer digital twin modeling framework to enhance abstraction, reusability, and efficiency. • Introduces object-oriented encapsulation, inheritance, and polymorphism to improve model scalability. • Classifies production elements and builds unified abstract models to ensure model adaptability. • Defines behavior interfaces and supports polymorphism to handle diverse and dynamic workshop scenarios. Digital twin (DT) technology plays a crucial role in enabling real-time monitoring and optimization in smart manufacturing. However, existing DT modeling approaches often suffer from limited reusability, low efficiency, and poor adaptability, particularly in complex workshop environments. This paper proposes an object-oriented modeling mechanism tailored for workshop digital twins, leveraging the core principles of encapsulation, inheritance, and polymorphism. A five-layer modeling framework is introduced, ranging from meta models to instance models , which enables comprehensive and reusable modeling of workshop production elements. The encapsulation mechanism ensures data security via access permissions and interface binding; the inheritance mechanism supports scalable reuse through structured abstraction; and the polymorphism mechanism enables behavior flexibility across diverse equipment. A case study involving four types of equipment in a pharmaceutical packaging line demonstrates the proposed approach's effectiveness in improving modeling efficiency, accuracy, and fidelity. [ABSTRACT FROM AUTHOR]