Feature-based design by volumetric machining features

Abstract

Substantial research efforts have been spent on feature applications towards the integration of CAD and downstream manufacturing functions such as process planning. However, the majority of contemporary feature-based systems cannot handle the interactions of features in practical applications. Feature interactions cause problems in feature recognition as well as feature-based design systems. This paper presents an approach to represent and analyse features in a feature-based design system. In this system, a part is modelled by volumetric machining features, which are then decomposed into air volumes and material volumes. Geometric reasoning is used to evaluate and analyse the features incrementally during the design stage. Feature interactions are detected by the possible interactions among material volumes. Several interacted or face-contacted material volumes can be clustered into a single-material volume. For each material volume, a tool-swept volume is generated to represent the space to be removed in the machining process. The complete feature instancing process is governed by the validation rules to ensure that the part is manufacturable.