Machinability of Surfaces via Motion Analysis
The machinability of a surface describes its ability to be machined and the factors which affect this. These are independent of any material properties or cutting parameters but instead reflect an ability to replicate a desired tool path motion with sufficient control of the material removal process. Without this control there is a potential for surface defects and costly finishing stages.
Five-axis CNC milling machines are commonly used for machining complex free-form shapes. The processes required to obtain CNC instructions for a machine tool, starting from a target surface, are presented. An overview is first given and later formalised with mathematical methods. Specifically, a moving cutting tool is characterised by a tool path motion. Interpreting the moving cutter in terms of moving machine axes provides a diagnostic tool for detecting machining errors.
Examination of two case studies reveals different types of errors, machine-dependent and machine-independent. The contribution of geometry to machine-independent errors is discussed and related back to the machinability of a surface.
KeywordsMachinability Five-axis machine tool Tool path motion
The research is supported by the EPSRC research council (EP/L010321/1 and EP/L006316/1). The authors also thank Delcam International PLC for supporting the research presented in this paper.
- 1.Kalpakjian, S., Schmid, S.: Manufacturing Engineering and Technology, 5th edn. Pearson Publishing Company, Upper Saddle River (2006)Google Scholar
- 2.Choi, B.K., Kim, B.H., Jerard, R.B.: Sculptured surface NC machining. In: Handbook of Computer Aided Geometric Design, pp. 543–574 (2002)Google Scholar
- 3.Powermill 2014 Delcam PLC, January 2016. www.powermill.com
- 5.Suh, S., Kang, S., Ching, D., Stroud, I.: Theory and Design of CNC Systems. Springer, Heidelberg (2008). doi: 10.1007/978-1-84800-336-1
- 6.Doughty, S.: Mechanics of Machines. Wiley, New York (1988)Google Scholar
- 9.Zlatanov, D., Fenton, R.G., Benhabib, B.: Singularity analysis of mechanisms and robots via a velocity-equation model of the instantaneous kinematics. In: IEEE International Conference on Robotics and Automation (1994)Google Scholar
- 10.Hermle: Hermle C600 Series Brochure. Hermle, Gosheim (1999)Google Scholar
- 11.Alicona G5 InfiniteFocus Alicona Imaging GmbH, August 2016. http://www.alicona.com/products/infinitefocus/
- 12.Peters, J.: Geometric continuity. In: Farin, G., Hoschek, J., Kim, M. (eds.) Handbook on Computer Aided Geometric Design. Elsevier, Amsterdam (2002)Google Scholar
- 13.Powershape 2014 Delcam PLC, January 2016. www.powershape.com