STEP-based Feature modeller for STEP Compliant CNC

Feature-based modeling is one of key technologies to implement intelligent STEP compliant CNC, which can associate not only geometric and topological information, but also form features, tolerances, material properties and other information which may be used during the process planning and STEP-NC machining. This paper presents a machining feature-based modeler to build parts and exports them as the format of STEP AP224 file. The modeling system provides three main steps to construct a part: (1) selection of raw stock form stock library, (2) selection of predefined machining features according to ISO14649 to be subtracted from the part being designed, and (3) providing information to define the machining feature attributes such as feature size, position, orientation etc. This feature-based modeling system is implemented by using Microsoft C# and NX Open technology in UG NX6.0 environment.