As the motion accuracy of 5-axis machining centers directly influences the geometrical shape accuracy of the machined workpieces, accuracy enhancement of the 5-axis machining centers is strongly needed. To improve the shape accuracy during the machining by a 5-axis machine tool, a method that modifies the CL-data based on the motion trajectory errors normal to the machined surface at each command point has been proposed. In this study, the proposed method is applied to simultaneous 5-axis controlled machining to improve motion accuracy. A normal vector calculation method for the simultaneous 5-axis controlled motion is newly proposed, and the compensation method is applied to turbine blade machining by 5-axis controlled motion. Measurement tests of the cutting motion for blade shape machining by a ball-end mill were carried out with a different control mode of NC. The CL-data for the machining tool path was also modified based on the calculated trajectory of the tool center point. Experimental results reveal that the feed speed and machining accuracy significantly depend on the control mode of NC, and that the shape accuracy can be improved by applying the proposed compensation method without any decrease in motion speed.

1. [1] Y. Takeuchi and T. Watanabe, “Generation of 5-axis Control Collision-free Tool Path and Post Processing for NC Data,” CIRP Annals – Manufacturing Technology, Vol.41, Issue 1, pp. 539-542, 1992.
2. [2] J. Kaneko, “Visualization and Optimization Method for Multi Axis Controlled Machining Process,” J. of the Japan Society for Precision Engineering, Vol.78, No.9, pp. 757-762, 2012 (in Japanese).
3. [3] ISO 230-1, “Test Code for Machine Tools – Part 1: Geometric Accuracy of Machines Operating under No-Load or Quasi-Static Conditions,” 2012.
4. [4] S. Ibaraki and W. Knapp, “Indirect Measurement of Volumetric Accuracy for Three-axis and Five-axis Machine Tools: A Review,” Int. J. Automation Technol., Vol.6, No.2, pp. 110-124, 2012.
5. [5] S. Ibaraki, M. Sawada, A. Matsubara, and T. Matsushita, “Machining Tests to Identify Kinematic Errors on Five-axis Machine Tools,” Precision Engineering, Vol.34, No.3, pp. 387-398, 2010.
6. [6] S. Ibaraki and Y. Ota, “A Machining Test to Calibrate Rotary Axis Error Motions of Five-axis Machine Tools and its Application to Thermal Deformation Test,” Int. J. of Machine Tools & Manufacture, Vol.86, pp. 81-88, 2014.
7. [7] A. Velenosi, G. Campatelli, and A. Scippa, “Axis Geometrical Errors Analysis Through a Performance Test to Evaluate Kinematic Error in a Five Axis Tilting-rotary Table Machine Tool,” Precision Engineering, Vol.39, pp. 224-233, 2015.
8. [8] M. Tsutsumi, D. Yumiza, K. Utsumi, and R. Sato, “Evaluation of Synchronous Motion in Five-axis Machining Centers with a Tilting Rotary Table,” J. of Advanced Mechanical Design, Systems, and Manufacturing, Vol.1, No.1, pp. 24-35, 2007.
9. [9] R. Sato and M. Tsutsumi, “Dynamic Synchronous Accuracy of Translational and Rotary Axes,” Int. J. of Mechatronics and Manufacturing Systems, Vol.4, Nos.3-4, pp. 201-219, 2011.
10. [10] R. Sato, Y. Sato, K. Shirase, G. Campatelli, and A. Schippa, “Finished Surface Simulation Method to Predicting the Effects of Machine Tool Motion Errors,” Int. J. Automation Technol., Vol.6, No.8, pp. 801-810, 2014.
11. [11] M. Tomizuka, “Zero-phase Error Tracking Algorithm for Digital Control,” Trans. of the ASME, J. of Dynamic Systems, Measurement, and Control, Vol.109, pp. 65-68, 1987.
12. [12] R. Sato and M. Tsutsumi, “High Performance Motion Control of Rotary Table for 5-Axis Machining Centers,” Int. J. Automation Technol., Vol.1, No.2, pp. 113-119, 2007.
13. [13] P. K. Kulkarni and K. Srinivasan, “Optimal Contouring Control of Multi-Axial Feed Drive Servomechanisms,” Trans. of the ASME, J. of Engineering for Industry, Vol.111, pp. 140-148, 1989.
14. [14] C.-S. Chen and L.-Y. Chen, “Cross-coupling Position Command Shaping Control in a Multi-axis Motion System,” Mechatronics, Vol.21, pp. 625-632, 2011.
15. [15] Y. Koren, “Cross-coupled Biaxial Control for Manufacturing Systems,” Trans. of the ASME, J. of Dynamic Systems, Measurement, and Control, Vol.102, pp. 65-68, 1980.
16. [16] B. Sencer, Y. Altintas, and E. Croft, “Feed Optimization for Five-axis CNC machine Tools with Drive Constraints,” Int. J. of Machine Tools & Manufacture, Vol.48, pp. 733-745, 2008.
17. [17] Y. Sun, Y. Zhao, Y. Bao, and D. Guo, “A Smooth Curve Evolution Approach to the Feedrate Planning on Five-axis Toolpath with Geometric and Kinematic Constraints,” Int. J. of Machine Tools & Manufacture, Vol.97, pp. 86-97, 2015.
18. [18] FANUC Ltd., “FANUC 30i/31i/32i Operator’s Manual,” B-63944EN, 2011.
19. [19] Siemens AG, “SINUMERIK Tool and Mold Making Manual,” No.6FC5095-0AB20-0BP0, 2007.
20. [20] Dr. Johannes Heidenhain GmbH, “iTNC530 Information for the Machine Tool Builder,” 363 808-2C, 2011.
21. [21] T. Otsuki, H. Sasahara, and R. Sato, “A Method for Evaluating the Speed and Accuracy of CNC machine Tools,” Proc. of the 9th Int. Conf. on Leading Edge Manufacturing in 21st Century (LEM21), No.034, 2017.
22. [22] T. Otsuki, H. Sasahara, and R. Sato, “Method for Generating CNC Programs Based on Block-Processing Time to Imorive Speed and Accuracy of Machining Curved Shapes,” Precision Engineering, Vol.55, pp. 33-41, 2018.
23. [23] C.-S. Chena, Y.-H. Fanb, and S. P. Tseng, “Position Command Shaping Control in a Retrofitted Milling Machine,” Int. J. of Machine Tools & Manufacture, Vol.46, pp. 293-303, 2006.
24. [24] T. Miura and Y. Yamaguchi, “Machine Control Method, Published Unexamined Patent Application,” Japan Patent Office, H08-185211, 1996 (in Japanese).
25. [25] T. Ueguchi and S. Maekawa, “CNC Data Correction Method,” Published Unexamined Patent Application, Japan Patent Office, H09-269808, 1997 (in Japanese).
26. [26] R. Sato, S. Hasegawa, K. Shirase, M. Hasegawa, A. Saito, and T. Iwasaki, “Motion Accuracy Enhancement of 5-axis Machine Tools by Modified CL-data,” Int. J. Automation Technol., Vol.12, No.5, pp. 699-706, 2018.