Kinematical Smoothing of Rotary Axis near Singularity Point

Abstract:

This paper deals with singular configurations of a 5-axis machine tool in high speed milling which may lead to the appearance of large incoherent movements of rotary axes near singularity points. These movements generate slowdowns of the actual feedrate during the execution of the tool path, which affect quality and productivity. Thus, this paper proposes a method to detect these behaviors during machining simulation and correct the tool path. Unlike the literature methods, this correction consists in modifying the tool axis orientation by going through the singularity point while respecting maximum velocity, acceleration and jerk of the rotary axis. For that purpose, the initial articular positions of the rotary axis near the singularity point are fitted with B-spline curves, modified and finally discretized for linear interpolation. Experimental investigations on a test part are carried out to show the efficiency of the method.

• Periodical: Materials Science Forum (Volumes 836-837)
• Pages: 501-508
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.836-837.501
• Online since: January 2016
• Authors: Laureen Grandguillaume, Sylvain Lavernhe, Christophe Tournier*
• Keywords: 5-Axis Machining, Inverse Kinematical Transformation, Singularity, Tool Path Computation

References

[1] J-H. Kim, B-S. Ryuh, G.R. Pennock, Development of a trajectory generation method for a five-axis NC machine, Mechanism and Machine Theory, 36 (2001) 983-996.

DOI: 10.1016/s0094-114x(01)00030-1

[2] A. Lasemi, D. Xue, P. Gu, Recent development in CNC machining of freeform surfaces: A state-of-the-art review, Computer-Aided Design, 42 (2010) 641-654.

DOI: 10.1016/j.cad.2010.04.002

[3] K. Erkorkmaz and Y. Altintas. High speed CNC system design. Part I: jerk limited trajectory generation and quintic spline interpolation. International Journal of Machine Tools and Manufacture, 41(2001) 1323–1345.

DOI: 10.1016/s0890-6955(01)00002-5

[4] X. Beudaert, P-Y. Pechard, C. Tournier, 5-axis tool path smoothing based on drive constraints, International Journal of Machine Tools and Manufacture, 51 (2011) 958–965.

DOI: 10.1016/j.ijmachtools.2011.08.014

[5] Y.H. Jung, D.W. Lee, J.S. Kim, H.S. Mok, NC post-processor for 5-axis milling machine of table-rotating/tilting type, Journal of Materials Processing Technology, 130 (2002) 641-646.

DOI: 10.1016/s0924-0136(02)00725-2

[6] A. Affouard, E. Duc, C. Lartigue, J. -M. Langeron, P. Bourdet, Avoiding 5-axis singularities using tool path deformation, International Journal of Machine Tools and Manufacture, 44 (2004) 415-425.

DOI: 10.1016/j.ijmachtools.2003.10.008

[7] M. Munlin, S.S. Makhanov, E.L.J. Bohez. Optimization of rotations of a five-axis milling machine near stationary points, Computer-Aided Design, 36 (2004) 1117-1128.

DOI: 10.1016/s0010-4485(03)00164-7

[8] J. Yang, Y. Altintas. Generalized kinematics of five-axis serial machines with non-singular tool path generation, International Journal of Machine Tools and Manufacture, 75 (2013) 119-132.

DOI: 10.1016/j.ijmachtools.2013.09.002

[9] K. Soerby, Inverse kinematics of five-axis machines near singular configurations, International Journal of Machine Tools and Manufacture, 47 (2007) 299-306.

DOI: 10.1016/j.ijmachtools.2006.03.011

[10] C. Tournier, C. Castagnetti, S. Lavernhe, F. Avellan. Tool path generation and post-processor issues in five-axis high speed machining of hydro turbine blades, Fifth International Conference on High Speed Machining, Metz, France, (2006).