Geometric modeling is the core part of most CAD/CAM applications. The manufacturing industry consists of a wide range of experts with different views, skills, and knowledge of the design process that evolved over long period. Although they want to retrieve the geometric information, there is not an integrated and widespread use of geometric data throughout the lifecycle.
This thesis focuses on the database driven CAD integration to support CAD data management and sharing. Every engineering application has its own data model. A model has a lot of information including geometry, tolerance, material, and manufacturing plan. Commercial CAD systems store design model in their own file-based database. Data storage and API function of the commercial CAD systems are examined with respect to their advantages and limits to help implementing a database driven CAD systems.
A prototype CAD system has been implemented which uses the OpenDIS interface which is implemented using OpenCascade geometric kernel and the Objectstore object-oriented database. The STEP methodology is used as the database schema. This CAD system has been applied to the hull design of a ship in order to verify the usefulness of the interface. The database can be accessed from commercial CAD systems such as SolidWorks or Unigraphics. The data access module from a commercial CAD system is developed using the CAD system`s native API, ObjectStore API functions, and ActiveX . The efficiency of the importing designer`s working space from the database has been evaluated, such as search for attributes and zones.