Modeling and Control of Twin Parallel-Axis Linear Servo Mechanisms for High-Speed Machine Tools

Wu-Sung Yao, Fu-Yun Yang, Mi-Ching Tsai

Abstract


This paper presents a synchronous control scheme for a twin parallel-axis linear servo mechanism with mechanical coupling which appears inherently in the so-called box-in-box configuration of machine tools. To identify the two-port mathematical model, a multi-variable identification method is developed to construct a dynamic model of the controlled servo mechanism. Moreover, a synchronous controller framework based on the identified model is proposed to reduce position and velocity errors of the two coupled linear servomotors. To demonstrate the capacity of the mathematical model as well as the effectiveness of the control scheme, a gantry-type platform was utilized as an illustrated example, where the steady-state synchronization error reaches 0.5 m with a velocity of 830mm/s.

Keywords


dynamic modeling; synchronous control; linear servomotor; system identification

References


  1. R. D. Lorenz and P. B. Schmidt, "Synchronized motion control for process automation," Industry Applications Society Annual Meeting, San Diego, CA , USA, 1989, pp. 1693-1698.
    doi: 10.1109/IAS.1989.96869
  2. P. Sarachik and R. J.R., "A 2-dimensional feedback control system," Transactions of the American Institute of Electrical Engineers, vol. 76, part 2, pp. 55-61, 1957 1957.
  3. FANCU AC servo motor Alpha-series, Parameter Manual, FANCU Corp., 1994.
  4. 840D/FM-NC Description of functions, special functions (Part 3), SIEMENS,1999.
  5. M. F. Hsieh, C. J. Tung, W. S. Yao, M. C. Wu, and Y. S. Liao, "Servo design of a vertical axis drive using dual linear motors for high speed electric discharge machining," International Journal of Machine Tools and Manufacture, vol. 47, no. 3-4, pp. 546-554, 2007.
    doi: 10.1016/j.ijmachtools.2006.05.011
  6. J. X. Yang, "The identification and control of a twin linear servo system with mechanical coupling," M.S. thesis, Department of Mechanical Engineering, National Cheng Kung University, Taiwan, 2003.
  7. G. T. C. Chiu and M. Tomizuka, "Coordinated position control of multi-axis mechanical systems," Journal of Dynamic Systems, Measurement, and Control, vol. 120, no. 3, pp. 389-393, 1998.
    doi: 10.1115/1.2805413
  8. D. Sun, "Position synchronization of multiple motion axes with adaptive coupling control," Automatica, vol. 39, no. 6, pp. 997-1005, 2003.
    doi: 10.1016/S0005-1098(03)00037-2
  9. M. F. Hsieh, W. S. Yao, and C. R. Chiang, "Modeling and synchronous control of a single-axis stage driven by dual mechanically-coupled parallel ball screws," The International Journal of Advanced Manufacturing Technology, vol. 34, no. 9-10, pp. 933-943, 2007.
    doi: 10.1007/s00170-007-1135-4
  10. Y. Koren, "Cross-coupled biaxial computer control for manufacturing systems," Journal of Dynamic Systems, Measurement, and Control, vol. 102, no. 4, pp. 265-272, 1980.
    doi: 10.1115/1.3149612
  11. Y. Koren and C. C. Lo, "Advanced controllers for feed drives," CIRP Annals - Manufacturing Technology, vol. 41, no. 2, pp. 689-698, 1992.
    doi: 10.1016/S0007-8506(07)63255-7
  12. M. G. M. Lammers, "Linears lead in ultrasmooth motion," Machine design, vol. 66, no. 17, pp. 60-64, 1994.
  13. K. Srinivasan and P. K. Kulkarni, "Cross-coupled control of biaxial feed drive servomechanisms," Journal of Dynamic Systems, Measurement, and Control, vol. 112, no. 2, pp. 225-232, 1990.
    doi: 10.1115/1.2896129
  14. M. Tomizuka, J. S. Hu, T. C. Chiu, and T. Kamano, "Synchronization of two motion control axes under adaptive feedforward control," Journal of Dynamic Systems, Measurement, and Control, vol. 114, no. 2, pp. 196-203, 1992.
    doi: 10.1115/1.2896515
  15. X. C. Xi, A. N. Poo, G. S. Hong, and F. Huo, "Experimental implementation of taylor series expansion error compensation on a bi-axial cnc machine," The International Journal of Advanced Manufacturing Technology, no. 2010.
    doi: 10.1007/s00170-010-2843-8
  16. W. S. Yao, "Design of linear servo systems for high speed machine tools," Ph.D. dissertation, Department of Mechanical Engineering, National Cheng Kung University, Taiwan, 2002.
  17. D. Zhao, S. Li, F. Gao, and Q. Zhu, "Robust adaptive terminal sliding mode-based synchronised position control for multiple motion axes systems," IET Control Theory & Applications, vol. 3, no. 1, pp. 136-150, 2009.
    doi: 10.1049/iet-cta:20070272


Full Text: PDF HTML

Refbacks

  • There are currently no refbacks.


Copyright © 2011-2018 AUSMT ISSN: 2223-9766