Feature based design of rotational parts based on step

Fidan, Tahir
The implicit and low-level part definition data, provided by geometric modeling cannot be used by downstream applications. Therefore, feature based modeling concept has been introduced to integrate CAD and downstream applications. However, due to the lack of implicit and explicit standard representations for features and unmanageable number of possible predefined features without standardization, feature based modeling approach has proved to be inadequate. STEP AP224 provides a standard for both implicit and explicit representations for manufacturing features. This thesis presents STEP AP224 features based modeling for rotational parts. The thesis covers features extracted from STEP AP224 for rotational parts and their definitions, classifications, attributes, generation techniques, attachment methods and geometrical constraints. In this thesis a feature modeler for rotational parts has been developed. STEP AP224 features generated are used as the basic entities for part design. The architecture of the proposed system consists of two three phases: (1) feature library, (2) feature modeler and (3) preprocessor. Preprocessor responsible from STEP-XML data file creation. The data file created can be used in the integration CAPP/CAM systems without using a complex feature recognition process. An object-oriented design approach is used in developing the feature modeler to provide incremental system development and reusability.


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Citation Formats
T. Fidan, “Feature based design of rotational parts based on step,” M.S. - Master of Science, Middle East Technical University, 2004.