Recognition of isolated prismatic features from feature based models

Abstract

The objective of this study is to develop a feature recognition algorithm to convert geometrical and topological data of a feature from Computer Aided Design (CAD) system to an identifiable manufacturing feature that can be used in Computer Aided Manufacturing (CAM) system. An algorithm was developed by using Visual Basic for Application (VBA) as the programming language and Application Programming Interface (API) as the interface to interact with the CAD program. The features to be recognized by this algorithm are isolated prismatic pocket namely square slot, square step, square notch and square open pocket. The algorithm was also able to recognize non-orthogonal features as well as the dimension of the blank workpiece needed to machine the design. The algorithm utilizes the connection of the vertices in a design to determine the type of machining feature on the design as well as the location of the feature in form of coordinates. The evaluation of the algorithm shows significant improvement in recognition time compared to pattern matching algorithm.