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Model Updating Using the Closed-loop Natural Frequency

폐루프 공진 주파수를 이용한 모델 개선법

  • 정훈상 (한국과학기술원 기계공학과) ;
  • 박영진 (한국과학기술원 기계공학과)
  • Published : 2004.03.01

Abstract

Parameter modification of a linear finite element model(FEM) based on modal sensitivity matrix is usually performed through an effort to match FEM modal data to experimental ones. However, there are cases where this method can't be applied successfully; lack of reliable modal data and ill-conditioning of the modal sensitivity matrix constitute such cases. In this research, a novel concept of introducing feedback loops to the conventional modal test setup is proposed. This method uses closed-loop natural frequency data for parameter modification to overcome the problems associated with the conventional method based on modal sensitivity matrix. We proposed the whole procedure of parameter modification using the closed-loop natural frequency data including the modal sensitivity modification and controller design method. Proposed controller design method is efficient in changing modes. Numerical simulation of parameter estimation based on time-domain input/output data is provided to demonstrate the estimation performance of the proposed method.

Keywords

References

  1. Mottershead J. E. and Friswell, M. I., 1993, 'Model Updating in Structural Dynamics: a Survey,' Journal of Sound and Vibration, Vol. 167, No. 2, pp. 347-375 https://doi.org/10.1006/jsvi.1993.1340
  2. Friswell, M. I., 1996, Finite Element Model Updating in Structural Dynamics, Kluwer academic publishers, London, Chap. 5
  3. Dascotte, E., 1990, 'Practical Application of Finite Element Tunning Using Experimental Modal Data,' Proceedings of the 8th International Modal Analysis Conference, Florida, pp. 1032-1037
  4. D'Ambrogio, W. and Fregolent, A., 2000, 'The use of Antiresonances for Robust Model Updating' Journal of Sound and Vibration, Vol. 236, No. 2, pp. 227-243 https://doi.org/10.1006/jsvi.1999.2987
  5. Li, S., Shelly S. and Brown, D., 1995, 'Perturbed Boundary Condition Testing,' Proceedings of the 13th International Modal Analysis Conference 1, pp. 902-907
  6. Nalitolera, N. G., et al., 1992, 'A Mass or Stiffness Addition Technique for Structural Para- meter Updating,' The International Journal of Analytical and Experimental Modal Analysis, Vol. 7, Num. 3, pp. 157-168
  7. Cha P. D., et al., 2000, 'Model Updating Using an Incomplete Set of Experimental Modes,' Journal of Sound and Vibration, Vol. 233, No. 4, pp. 587-600
  8. Gordis, J. H., 1999, 'Artificial Boundary Conditions for Model Updating and Damage Detec- tion,' Mechanical Systems and Signal Processing, Vol. 13, No. 3, pp. 437-448 https://doi.org/10.1006/mssp.1998.0192
  9. Nalitolela N., et al., 1993, 'Undating Model Parameters by Adding an Imagined Stiffness to the Structure,' Mechanical systems and signal pro- cessing, Vol. 7, No. 2, pp. 161-172 https://doi.org/10.1006/mssp.1993.1005
  10. Nalitolela N., et al., 1993, 'Undating Model Parameters by Adding an Imagined Stiffness to the Structure,' Mechanical systems and signal pro- cessing, Vol. 7, No. 2, pp. 161-172 https://doi.org/10.1006/mssp.1993.1005
  11. Jung, H. S., et al., 2001, 'Model Updating Using the Feedback Exciter,' Asia-Pacific Vibra- tion Conference 2001, Hangzhou, China, pp. 1020-1024
  12. Juang, J. N., Applied System Identification, Prentice hall, New Jersey, chap. 6
  13. Juang, J. N., Applied System Identification, Prentice hall, New Jersey, chap. 5
  14. Alvin, K. F. and Park, K. C. 1994, 'Se- cond-order Structural Identification Procedure Via State-space-based System Identification,' AIAA Journal, Vol. 32, No. 2, pp. 397-406 https://doi.org/10.2514/3.11997