Digital twins, an innovative technology propelled by data and models, play a seminal role in the digital transformation and intelligent upgrade of ships. This study introduces a digital twin methodology for the real-time monitoring of ship structure deformation fields, based on finite discrete strain data, and a visualization tool framework is developed using virtual reality technology. First, the inverse Finite Element Method (iFEM) is employed to derive the deformation field of the ship structure in real time using sensor strain data. Secondly, the deformation field data obtained based on the iFEM algorithm is converted into general visualization data conducive to interpretation within virtual reality (VR) applications. Lastly, a digital twin software tool is built to enable synchronous responses and interactions between the virtual scene and the physical scene, directly superposing particular virtual objects (data acquired by sensors, computer-aided design (CAD) virtual models, and deformation field cloud images) onto the physical scene in real time. The digital twin tool embodies a virtual reality visualization system framework integrating the physical data measurement, reconstruction, analysis, expression, storage, rendering, and interaction of deformation field data. Through practical application, the flexibility, effectiveness, and compatibility of the developed prototype tool are verified. According to the results, the system can enhance the efficiency of scientific communication, model validation, and interdisciplinary sharing during the analysis and evaluation of the mechanical properties of ship structures.

Lightweight design and vibration damping design of the lashing bridge are deemed as two critical issues having nagged designers. The application of knowledge-based engineering (KBE) technology to intelligent design and optimisation can be divided into four steps. The first step is to construct a knowledge base system. In the second step, the design variables are chosen and the intelligent design is achieved by applying the knowledge base to structural models and checking structural reasonability. Strength analysis and vibration response analysis are also conducted in the third step, and the appropriate optimisation design flow and the optimisation algorithm are constructed. The last step is to apply KBE technology to the multi-objective optimisation process to get the best-optimised design. The design and optimisation results show that KBE-based design method ensures the reasonability, economy and safety of the design structure, and dramatically improves the design efficiency.