STEPNC++-AnEffectiveToolforFeature-basedCAM-CNC.PDF

STEPNC++ - An Effective Tool for Feature-based CAM/CNC 1 2 3 4 5 John Michaloski , Thomas Kramer , Frederick Proctor , Xun Xu , Sid Venkatesh , and David Odendahl6 1-3 Intelligent Systems Division, MS8230, National Institute of Standards and Technology 100 Bureau Drive, Gaithersburg, MD 20899, USA Email: 1 john.michaloski@, 2 thomas.kramer@, 3 ctor@, 4 Department of Mechanical Engineering, University of Auckland, 20 Symonds Street, Auckland, New Zealand Email: x.xu@auckland.ac.nz 5,6 Boeing Aircraft, Seattle, WA Email: 5 sid.venkatesh@, 6 david.j.odendahl@ Abstract This chapter discusses the realization of direct translation of feature-based CAM files into feature-based CNC part program files. The information infrastructure that allows this to happen is STEP-NC, as described by ISO 14649 Parts 10 and 11. Among the many benefits cited for STEP-NC, the elimination of the costly and inefficient process of post-processing using one standard CNC definition is most commonly cited. However, this chapter argues a much greater benefit can be found using STEP-NC to resolve the CAM/CNC impedance mismatch where CAM comprehensive process information is reduced into motion primitives. The CAM/CNC impedance mismatch and resulting lack of process information make intelligent machining difficult. Given this perspective, a demonstration system was developed to show that feature-based CNC is possible with STEP-NC, which preserves more feature- based CAM process knowledge to make intelligent machining possible. The demonstration system incorporates: 1) part representation using STEP-NC Part 21 files, 2) reading and analyzing feature-based elements of the STEP-NC, 3) translation into a