Contoured edge slice generation in rapid prototyping via 5-axis machining

Rapid prototyping, though a relatively new discipline, has proven to be a v aluable tool in the reduction of the time and cost associated with developi ng new products. The value of rapid prototyping shows the promise of increa sing even further as it matures and offers higher quality parts, in less li me, and for lower costs. Improvements in these areas are all addressed in c urrent rapid prototyping research in various ways. This paper presents a me thod for greatly improving the geometric accuracy, and thus the overall qua lity, of rapid prototype parts by making use of 5-axis machining. An algori thm is presented to generate the contoured edge slices for the rapid protot ype parts in several Levels of complexity. A simple algorithm is presented to generate a single edge contour for each section of the slice, and a more complex algorithm is also presented to allow for the 5-axis machining of " sub-layers" within a slice. It will be shown that sub-layer 5-axis machinin g provides the possibility to produce the most accurate rapid prototype par ts on the market today. The benefits and limitations of the process will be enumerated and summarized. An inexpensive design for the implementation of a 5-axis machine configuration for a proposed sheet-based rapid prototypin g process will be presented. A novel characteristic of the proposed process is that it does not require that the sheets be produced independently and post-assembled via a registration system. The process allows for the parts to be built up on a platen as the layers are cut, thus removing the need fo r a registration system and eliminating post-assembly errors. Sample parts and algorithm verification will also be presented. (C) 2001 Elsevier Scienc e Ltd. All rights reserved.