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With the rapid development of 3D CAD technology, 3D assembly process is playing an important role in the on-site assembly. A closed-loop control method and three-dimensional site visualization technology site is presented. The methodology takes into account CAD design stage, assembly process design, site assembly and site inspection. The method includes three key technologies: the verification process technology of three-dimensional assembly process, optimization and process simulation techniques of site assembly, closed-loop control technology of assembly process quality inspection. Finally, the method and technology has applied in the actual assembly, and achieved good results.

The assembly of ship blocks is achieved through welding. To get a high level of closure accuracy, finite element analysis (FEA) is always needed to predict the welding deformation. However, the fast automatic mesh generation technique during the finite element method (FEM) for the ship assembly is not mature enough yet. Due to the complex ship architecture, during FEA, the model must be built up manually in most cases. This process is complicated and the errors are easy to occur. Consequently, the efficiency of FEA during the ship assembly is highly affected. Automatic mesh generation is a key factor restricting the development of FEM, since the quality and speed of the mesh generation directly influence the accuracy of calculation and the efficiency of analysis. In the field of marine engineering and aerospace engineering, the mesh elements are required to be quadrilateral. However, the technique of the quadrilateral mesh generation is still more difficult and less mature than that of the triangular mesh generation. This work proposed a hybrid mesh generation algorithm, borrowing the advantages from both the quad-morphing algorithm and the paving algorithm as well as considering the factor of multi-constraints. An example case is also given to illustrate the result of this proposed algorithm.

Assembly processes are very complex and hard to setup in one-time for large-scale products. Much assembly information is produced in various assembly processes and such information has not integrated or considered for next assembly processes. This leads to problems of deciding manufacturing tolerance of productions quality in the final assembly process. An object-oriented assembly information model and visualization for VAFM (Virtual Assembly Fat Model), is presented in the paper. The information modeling for assembly processes considers not only geometry data, but also non-geometry information, and those information produced by assembly process evolve, mature and derived during the whole assembly process. The paper presents modeling language based on XML and distributed storage based BSON for assembly object. The visualization of VAFM is also presented.

Large-scale component assembly, such as the installation of aircraft wings and ship section etc., is usually high cost, long cycle. Virtual assembly simulation gives the possibility of direct and visual perceive of assembly before the actual assembly using digital prototype. A new virtual assembly model, called VAFM (Virtual Assembly Fat Model), is presented. It integrates not only geometry data, but non-geometry information is embedded. All information of model will evolve, mature and derived gradually, from thin to fat, during the whole assembly process. The paper gives the definition of a VAFM, its framework and the evolution rules of the fat model. Meanwhile the paper design the modeling language based XML. Finally, the visualization of VAFM is also presented..

Within a shipyard, designers have their own design objectives and moreover apply different software on heterogeneous hardware platforms; nevertheless requested collabtive operation still remains in the comple design circumstance. The paper presents a data hub model to sovle this problem and improve effectiveness and efficiency for ship design. The model is simulation-driven and consists of two main parts, including data management and integrated simulation environment. The data management processes the simulation-based design data storage, access and transformation. The integrated simulation environment bridges the gap among the multidisciplinary domain including CAD geometry, CAE, virtual navigation, kinematics and dynamics simulation. In addition, an application is developed to evaluate the validity of data hub model for ship design.