A VOLUME DECOMPOSITION APPROACH TO PROCESS PLANNING FOR PRISMATIC PARTS WITH DEPRESSION AND PROTRUSION DESIGN-FEATURES

This paper proposes a volume decomposition approach to building an int erface which bridges the gap between a 3D CAD model and an automated p rocess planning system. The volume decomposition approach partitions t he whole machining volume, which needs to be removed from the raw mate rial to produce the finished part, into some machinable features. Once the machinable features of a part are found, the machining of the par t can be viewed as material removal for a series of machinable feature s. The tasks involved in volume decomposition are: (1) extraction of m achining volume from the part model; (2) decomposition of the machinin g volume into machinable features; and (3) determination of procedures required for cutting out the machinable features. By means of a volum e decomposition process, we can effectively and efficiently resolve th e problem of interfacing CAD with a process planning system. An even m ore noticeable property of such a decomposition approach is concerned with its sound regard to the design model which comprises both depress ion and protrusion features. A prototype system, which integrates alto gether feature-based design, volume decomposition and NC planning, is presented in this paper as well to validate the proposed approach.