| The ship industry in the world is developing rapidly in the 21 century. In the future, ship building will orient to numeral and network in order to improve design capability. Agility can improve the response to market demand and has the characteristic to realize manufacturing system. Numerical Control equipments play an important role in supporting the agility in ship building. A good STEP-NC architecture can bring in agility manufacturing.According to the contents of STEP-NC standard, Application Protocol of STEP-NC is analyzed, and data model for contour milling in STEP-NC Application Protocol is expanded. Based on principle and methodology of STEP-NC, architecture of STEP-NC controller is proposed, design and construction of components in STEP-NC controller is given in detail. The prototype machine tool equipped with STEP-NC controller is developed. The main contents of dissertation are as followings:1. The format of apply physical file is analyzed based on AAM , ARM and AIM. According to cutting technology characteristics in CNC, data model for Profile Cutting Data Model is set up. Through analysis of technology condition of profile cutting, technology features is summarized. ARM and AP238 AIM are established.2. Based on structural requirement of STEP-NC controller and realization strategy, using division functions of STEP-NC controller into hierarchy structure, conceptual framework for intelligent STEP-NC controller is built up; and static model and behavioral model for STEP-NC controller is presented which gives formal and description of system static and dynamic behavior. 3. According to syntax characteristics, geometry information elements and topology relationship of instances, data flow is described in semantic analysis. A method for abstracting machining feature is presented, and an interpreter model for STEP-NC controller is designed, based on discussion of solid recognition and abstracting method for attribute of solid parameters.4. PID algorithm is given in motion controller's characteristics. Two methods are used which are knowledge-based PID tuning and error-based fuzzy PID method in order to tune controller parameters. And through Matlab simulation, curves are collected and analyzed which reflect system static and dynamic accuracy. Through comparison of two methods, corresponding advantage and suitable condition are determined.5. Realizing strategy in web services of NC devices is summarized according to analysis of NC machining of characteristics and requirement of web based NC machining in ship building. In order to make agent model following web services specification, adding web services to conventional agent model, a web service agent model compliant to STEP-NC is proposed, whose key techniques and application model are researched. A prototype CNC system for web ship building is established.
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