Generating alternative interpretations of machining features

Abstract

One of the major difficulties in extracting machining features is the lack of a systematic methodology to generate alternative ways of manufacturing a machined part. Most of the early research in feature extraction and process planning has nor considered this aspect, and has focused on the generation of a single interpretation. In this paper we propose a feature-based approach to generating alternative interpretations of machining features from a feature-based design model. The proposed approach simplifies the generation of alternative machining feature models by using information on feature which is captured and maintained during feature-based modelling and machining feature extraction. A set of machining features is incrementally extracted during the feature-based design process of a machined part. A feature conversion process converts each design feature into a machining feature or a set of machining features by using information on the geometry and the feature. Using reorientation, reduction, and/or splitting operations, alternative models are generated from the sets of extracted machining features. During the execution of each operation, unpromising models are pi-lined by using criteria such as minimising the number of accessibility directions. The machining features and their precedence relationships are represented in a STEP-based machining feature graph for the purpose of data exchange.