Research On Key Technologies Of Soft Platform Supporting Ship Digital Design

With the ship function and structure becoming more and more complicated, endless changes of costumer demand and intense competition in the marketing; it is very difficult for traditional CAD technology to adapt to modern shipbuilding requirements. At this stage, what the market demands is to shorten the design cycle, improve design efficiency, ensure design quality and reduce design defects. With these requirements modern ship industry appears the new mode to adapt to the development, the digital shipbuilding becomes hot point, and it brings new ideas and technical supports to the shipbuilding area, thus it need adopt these new technologies to solve the design problems in order to improve the maximum level of the process in ship designing, which is the starting point of this paper.Digital shipbuilding involves a wide range of technical areas, this paper is focuses on thebasis of technical support, builds an open, intelligent, distribution, coordination of multi-user support ship resource integration software platform through the study of these technologies. The study includes:1) Digital modeling: Digital modeling which is based on hull surface building is the core of digital design. After building 3Dline-grid, the hull surface model is built and the data of hull is got, such as line shape of any location of hull surface, which used as the cabin and structure building. Based on 3D hull surface, the paper studies parametric cabin design, then the solid cabin model is established, and the factor capacity is acquired. Using the digital hull surface as restriction to define the location of structure, using the product definition of the object-oriented framework to create 3D model of the hull structure in a graphical interface, and change them at the interactive way. The life-cycle digital model of ship product is built basing on the parametric design; the product-related information of producing is saved in the product model in structure way in order to realize the entire process of product modeling and data sharing.2) Rapid modeling: Based on the research of ship digital modeling, the rapid modeling library and its structure are advanced with the ship structure of the virtual design technology, product modeling process optimizing, the structure component of the knowledge and organizations expression, the combination of digital designing technology and rapid product designing. Using the CBR (Case-Based Reasoning) technology to build knowledge library, using variable design technologies to build the model liarary, the PDM of ship research is processed trough the distributed database. Based on those ideas, a prototype system is developed to implement the quick modeling. 3) Digital collaboration: Based on the hull structure in the local digital modeling, collaborative applications developed, other departments can design, operation and manage at the same time through the network collaborative. For this reason, the design of the ship modeling 5-layer transmission framework and organizational model are advanced. This provides the interaction platform for the designer and designing software and manages the operation of cooperation members. To solve conflict problems among multi-user operation, basing on a centralized server and the browser's agents, it includes the development of modeling, modifying, assembly and the hull structure collaborative design system of product information management, in order to achieve product data model of the digital collaborative design and management in the ship design phase.To sum up, with the idea of digital ship-design, this thesis demonstrates how to develop a uniform ship-design platform and researches the key technologies supporting this platform. From the beginning of generating, on the basis of local digital ship modeling, the paper develops the net transmission frame which accords with the characters of ship design, furthermore improves the capability of transmission framework, and finally integrates local and network techniques into the platform. This paper studies and develops a distributed rapid modeling system, with the concept of library for encapsulating process of design. Every client could share the same rapid modeling system, establish digital ship structure cooperatively and manage each application of the process. Because of this rapid modeling system, design circle could be shortened substantially and the ship design task also could be completed quickly and efficiently, at the same time, designer could spend less time to learn how to use the software, so that they can dive more energy into the process of design.Meanwhile, the digital model which is established during designing could be applied as a uniform management model for each stage, therefore it can avoid the reconstruction of different stages model for incompatibleness. Furthermore, by using the virtual digital model we could decrease the cost of manpower, material resources and time, reduce the cost of ship construction, shorten the circle of ship construction, improve the success rate of product development and enhance our ability to adapt market changes quickly.