Computer-Aided Design &Applications, PACE(2), 2012, 57-68
© 2012 CAD Solutions, LLC, http://www.cadanda.com
57
Developing a General Postprocessor for Multi-Axis CNC Milling Centers
Mihir Adivarekar
1
and Frank Liou
1
1
Missouri University of Science and Technology, liou@mst.edu
ABSTRACT
Most of the current college design and manufacturing curricula are primarily focused
on computer aided design (CAD), while less emphasis is given to computer aided
manufacturing (CAM). A great opportunity has been missed as the benefits of
CAD/CAM cannot then be fully learned. This paper proposes a general procedure for
developing a post processor, the interface between CAD/ CAM systems and NC
(Numerically Controlled) machines, for multi-axis CNC (Computer Numerical Control)
milling centers. The strategy comprises a systematic methodology of using CL data
information for developing a machine specific code. As an example, a post processor
was developed using Siemens NX- Post Builder commercial software for the five axis
CNC milling center- Fryer 5X with a FANUC series 18i-MB5 controller. The developed
post processor was validated by manufacturing five axes parts and by using different
CAM tool paths. Identified error sources could be corrected by modifying the
kinematic model of the post processor. Hence, implementation of this procedure for
the development of a post processor would streamline the process of integrating CAM
systems for multi-axis CNC milling centers. The integrated system is being used to
support research and education projects to accurately and quickly produce parts.
Keywords: computer aided manufacturing, post-processor, error compensation.
DOI: 10.3722/cadaps.2012.PACE.57-68
1 INTRODUCTION
Multi- axis machining constitutes three translational axes and some rotation axes. Enhancing machine
accuracy has been one of the main focuses of research on five-axis machine tools recently, but the
simultaneous presence of linear axes and rotation axes in five- axis machine tools, and complex
mathematical models resulting from the kinematic interactions, have made the application of related
techniques difficult [1, 2]
The number of the axis of a CNC machine implies the number of degrees of freedom that the
controller of the machine can be simultaneously interpolated. If the axis number increases, the