Observation of Thermal Influence on Error Motions of Rotary Axes on a Five-Axis Machine Tool by Static R-Test
Cefu Hong and Soichi Ibaraki
Department of Micro Engineering, Graduate School of Engineering, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto 606-8501, Japan
Thermal distortions are regarded as one of the major error factors in machine tools. ISO 230-3 and ISO 10791-10 describe tests to evaluate the influence of thermal distortions caused by linear motion and spindle rotation on the Tool Center Position (TCP). However, for five-axis machine tools, no thermal test is described for a rotary axis. Therefore, in this paper, a method for observing thermally induced geometric errors of a rotary axis with a static R-test is proposed. Unlike conventional thermal tests in ISO 230-3 and ISO 10791-10, where the thermal influence on the positioning error at a single point is tested, the present test measures the thermal influence on the error motions of a rotary axis. The R-test measurement clarifies how the error motions of a rotary table change with the rotation of a swiveling axis and how they are influenced by thermal changes. The thermal influence on the error motions of a rotary axis is quantitatively parameterized by geometric errors that vary with time.
-  S. Ibaraki and W. Knapp, “Indirect Measurement of Volumetric Accuracy for Three-axis and Five-axis Machine Tools: A Review,” Int. J. of Automation Technology, 6-2, 2012. (in print)
-  M. Tsutsumi and A. Saito, “Identification and Compensation of Systematic Deviations Particular to 5-axis Machining Centers,” Int. J. of Machine Tools and Manufacture, 43, pp. 771-780, 2003.
-  S. H. H. Zargarbashi and J. R. R. Mayer, “Assessment of Machine Tool Trunnion Axis Motion Error, Using Magnetic Double Ball Bar,” Int. J. of Machine Tools and Manufacture, 46, pp. 1823-1834, 2006.
-  R. Ramesh, M. A. Mannan, and A. N. Poo, “Error Compensation in Machine Tools – a Review Part II: Thermal Errors,” Int. J. of Machine Tools and Manufacture, 40, pp. 1257-1284, 2000.
-  H. Schwenke, W. Knapp et al., “Geometric Error Measurement and Compensation of Machines – An Update,” Annals of the CIRP, 57-2, pp.560-575, 2008.
-  ISO 230-3, “Test Code for Machine Tools – Part 3: Determination of Thermal Effects,” 2007.
-  ISO 10791-10, “Test Conditions for Machining Centers – Part 10: Evaluation of Thermal Distortions,” 2007.
-  A. K. Srivastava, S. C. Veldhuis, and M. A. Elbestawit, “Modeling Geometric and Thermal Errors in a Five-axis CNC Machine Tool,” Int. J. of Machine Tools and Manufacture, 35-9, pp. 1321-1337, 1995.
-  S. Weikert, “R-Test, a New Device for Accuracy Measurements on Five Axis Machine Tools,” Annals of the CIRP, 53-1, pp. 429-432, 2004.
-  B. Bringmann and W. Knapp, “Model-based ‘Chase-the-Ball’ Calibration of a 5-axis Machining Center,” Annals of the CIRP, 55-1, pp. 531-534, 2006.
-  ISO/CD 10791-6:2011, “Test Conditions for Machining Centers – Part 6: Accuracy of Speeds and Interpolations,” 2011.
-  IBS Precision Engineering: http://www.ibspe.com.
-  Fidia: http://www.fidia.it.
-  S. H. H. Zargarbashi and J. R. R. Mayer, “Single Setup Estimation of a Five-axis Machine Tool Eight Link Errors by Programmed End Point Constraint and On-the-fly Measurement with Capball Sensor,” Int. J. of Machine Tools and Manufacture, 49-10, pp. 759-766, 2009.
-  ISO 230-7, “Test Code for Machine Tools – Part 7: Geometric Accuracy of Axes of Rotation,” 2006.
-  S. Ibaraki, C. Oyama, and H. Otsubo, “Construction of an Error Map of Rotary Axes on a Five-axis Machining Center by Static Rtest,” Int. J. of Machine Tools and Manufacture, Vol.51, pp. 190-200, 2011.
-  S. Ibaraki, C. Hong, and C. Oyama, “Construction of an Error Map of Rotary Axes on a Five-axis Machining Center by Static R-test,” Proc. of the 6th Int. Conf. on Leading Edge Manufacturing in 21st Century (LEM21), 2011.
-  T. Erkan, J. R. R. Mayer, and Y. Dupont, “Volumetric Distortion Assessment of a Five-axis Machine by Probing a 3D Reconfigurable Uncalibrated Master Ball Artefact,” Precision Engineering, 35-1, pp. 116-125, 2011.
-  C. Hong, S. Ibaraki, and A. Matsubara, “Influence of Positiondependent Geometric Errors of Rotary Axes on a Machining Test of Cone Frustum by Five-axis Machine Tools,” Precision Engineering, 35-1, pp. 1-11, 2011.