Recognizing multiple interpretations of interacting machining features

A new feature recognition algorithm capable of recognizing interacting machining features and providing multiple interpretations is presented. For machined parts with interacting features, multiple equally valid sets of feature interpretations exist. The term 'multiple interpretations' is associated with identifying all the possible sets of machining features that can be recognized from the part. It represents multiple ways to decompose the total machinable volume into feature volumes. The feature recognition algorithm presented in the paper uses a boundary representation as input, and it is developed in two stages: (a) volume decomposition, and (b) reconstruction of features. In the first stage, the volume to be machined is identified and decomposed into small blocks by extending boundary faces of the part. In the second stage, feature volumes are reconstructed by systematically connecting the small blocks built in the previous stage. The current algorithm is capable of recognizing certain classes of interacting prismatic depression features, such as slots, steps, blind slots, blind steps, pockets, and prismatic holes, and it provides multiple interpretations. Test software is implemented and integrated with the i-deas solid modeller. Sample results demonstrating the algorithm are also presented.