STEP应用协议AP216（船模外形）实施方法的研究

【作者】 罗金炎；

【导师】 谢懋纲；

【作者基本信息】 中国船舶科学研究中心 ， 流体力学， 2001， 硕士

【摘要】 随着人类进入新的世纪，在船舶设计和制造领域的竞争日益加剧，使得人们越来越注重于通过降低成本、缩短生产周期、提高质量，来增强自己的竞争力，以赢得市场。采用STEP（ISO 10303）产品数据交换标准进行船舶产品数据信息的表达、交换和重复使用，进而进行整个生命周期产品数据管理是降低成本、提高效率的一种有效的方法。 STEP应用协议AP216（船模外形）是船舶STEP应用协议的一种，用以处理船舶设计中船体外型形状的产品数据定义。AP216是船舶性能研究系统中数据交换和共享的重要依据。本文主要对AP216的实施方法进行研究探讨，首先对AP216的内容进行了研究和分析，然后在此基础上设计了一个前置处理器将描述船体外形的型值数据转换成STEP中性文件，验证了STEP技术的可行性。 在集成环境下，经常需要在CAD、CAE、CAPP、CAM以及其它系统之间传递信息。由于所传递的数据量大，结构复杂，采用文件交换的方式很难满足要求，因此需要采用数据库交换方式。这是较高层次上的信息共享，也是STEP技术的目标。本论文提出了基于STEP AP216的集成系统的实现框架；通过分析EXPRESS语言的结构特点，对EXPRESS数据模式在关系型数据库上的实现进行了研究，定义了EXPRESS数据模式向关系型数据库模式转换的规则和方法；STEP数据库交换方法的实现还需要通过标准数据存取接口（SDAI）来访问数据，实现数据的共享。这方面的工作量较大实现起来有一定的难度。 STEP文件具有信息全面、结构紧凑、易读、无冗余及便于计算机处理等优点。本文又一次论证了开发STEP标准的必要性。更多还原

【Abstract】 The competition in shipbuilding is getting more and more sharp in the new century. In order to win the market, shipbuilders pay more attention to enhance their own adventage by saving cost, reducing production period and improving product quality. STEP(JSO 10303) is a effective technique for saving cost and improving productional efficiency,because it provides a unambiguous representation of a product in a computer interpretable neutral format throughout the lifetime of the product. The Application Protocol AP216(Ship Moulded Forms) is one of a series of shipbuilding application protocols, which aim to provide an integrated computer interpretable product model for ships. The Ship Moulded Forms which particular interest is the ship hull, which is the basis of data exchanging and sharing in ship performance research systems.This paper introduces the research of implementation method based on AP216.At first the application protocol is analyzed, then a pre梡rocessor is designed to convert offset of a ship into the STEP format. In integrated environment, it is necessary to share data among the CAX systems. File exchange way is difficult to fulfil the work, since there are mass data to exchange and the transform structure is complex. In the integrated environment,STEP sharing database is a valid way.The implementation architecture of STEP AP216 based integration system is defined in this paper. The implementation method of EXPRESS schema in a relational database is also intruduced. The standard data interface (SDAI) is briefly introduced. The STEP file has the ability of complement information, fine construct, easy processing by computer. The need of studying STEP is demonstrated again in the paper.更多还原