Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Limit Cycle Application to Friction Identification and Compensation

한계사이클을 이용한 마찰력의 규명 및 보상

  • 김민석 (한양대학교 기계설계학과 대학원) ;
  • 김명주 (한양대학교 기계설계학과 대학원) ;
  • 정성종 (한양대학교 기계공학부)
  • Published : 2005.07.01
Download PDF
⟨ Previous Next ⟩

Abstract

Friction is a dominant nonlinear factor in servomechanisms, which seriously deteriorates system accuracy. A friction compensator is indispensable to fabricate high-performance servomechanisms. In order to compensate for the friction in the servomechanism, identification of the friction elements is required. To estimate the friction of the servomechanism, an accurate linear element model of the system is required first. Tn this paper, a nonlinear friction model, in which static, coulomb and viscous frictions as well as Stribeck effect are included, is identified through the describing function approximation of the nonlinear element. A nonlinear element composed of two relays is intentionally devised to induce various limit cycle conditions in the velocity control loop of the servomechanism. The friction coefficients are estimated from the intersection points of the linear and nonlinear elements in the complex plane. A Butterworth filter is added to the velocity control loop not only to meet the assumption of the harmonic balance method but also to improve the accuracy of the friction identification process. Validity of the proposed method is confirmed through numerical simulations and experiments. In addition, a model-based friction compensator is applied as a feedforward controller to compensate fur the nonlinear characteristics of the servomechanism and to verify the effectiveness of the proposed identification method.

Keywords

References

  1. Tianhong Yan and Rongming Lin, 2003, 'Experimental Modeling and Compensation of Pivot Nonlinearity in Hard Disk Drives,' IEEE Trans. On Magnetics, Vol. 39, No.2, pp. 1064-1069 https://doi.org/10.1109/TMAG.2003.808601
  2. Kakino, Y., Ihara, Y. and Shinohara, A., 1993, Accuracy Inspection of NC Machine Tools by Double Ball Bar Method, Hanser Publishers, New York
  3. Brian Armstrong-Helouvry, Pierre Dupont, and Carlos Canudas De Wit, 'A Survey of Models, Analysis Tools and Compensation Methods for the Control of Machines with Friction,' Automatica, Vol. 30, No.7, pp. 1083-1138, 1994 https://doi.org/10.1016/0005-1098(94)90209-7
  4. Chu, C.N., Kim, G.D., Oh, Y.T. and Choi, Y.J., 1997, 'Frictional Behavior and Indirect Cutting Force Measurement in a Machining Center Using Feed Motor Current,' KSPE, Vol. 14, No.4, pp. 78-87
  5. Besancon-Vode, A. and Besancon, G., 1999, 'Analysis of a two-relay system configuration with application to Coulomb friction identification,' Automatica, Vol. 35, pp. 1391-1399 https://doi.org/10.1016/S0005-1098(99)00049-7
  6. Tan, K. K., Lee, T. H., Huang, S. N. and Jiang, X., 2001, 'Friction Modeling and Adaptive Compensation Using a Relay Feedback Approach,' IEEE Trans. On Industrial Electronics, Vol. 48, No.1, pp. 169-175 https://doi.org/10.1109/41.904577
  7. Slotine, J., J., E., and Li, W., 1991, Applied Nonlinear Control, Prentice Hall, Inc., New Jersey
  8. Atherton, D., 1975, Nonlinear Control Engineering, Van Nostrand Reinhold Co., London
  9. Min-Seok Kim, Sung-Chong Chung, 2003, 'Identification of nonlinear characteristics for precision servomechanisms,' Proc. of the 18th Annual Meeting, American Society for Precision Engineering, Portland, pp. 167-170
  10. Ljung, L., 1999, System Identification-Theory for the User, Prentice Hall PTR, New Jersey, pp. 79-246