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Estimating High-Frequency Damping of a Beam through Electro-Mechanical Signatures of Piezoelectric Wafer Mounted on the Beam

보에 부착된 압전웨이퍼의 전기역학적 신호를 통한 고주파수 대역 감쇠 추정

  • 신용재 (동아대학교 대학원 토목공학과) ;
  • 박현우 (동아대학교 인간환경융합공학부 토목공학과)
  • Received : 2016.11.29
  • Accepted : 2017.01.17
  • Published : 2017.02.01

Abstract

The high-frequency electro-mechanical signatures, which are excited and received by piezoelectric wafers mounted on a beam, are sensitive to incipient defect in a beam. Predicting the sensing range of the piezoelectric wafers is needed to effectively conduct damage assessment of a beam through utilizing their advantage. Damping of a beam plays the most important role in determining the sensing range among other features. This paper has proposed a scheme for estimating high-frequency damping of a beam through electro-mechanical signatures of piezoelectric wafers mounted on the beam. Considering damping effect while resonance of a beam evolves, wave perspective is adopted to formulate the electro-mechanical signatures of piezoelectric wafers. The damping of a beam is estimated through the least squares method minimizing the difference between the calculated and the measured damping ratio function values which are obtained from formulated and measured electro-mechanical signatures, respectively. The validity of the proposed scheme has been demonstrated through numerical and experimental examples using an aluminum beam with collocated piezoelectric wafers.

보의 표면에 부착된 압전웨이퍼를 통해 가진되고 측정되는 고주파수 대역의 전기역학적 신호는 보에 발생한 미세 손상에 매우 민감하다. 이러한 부착형 압전웨이퍼의 장점을 이용한 보의 손상 진단을 효과적으로 수행하기 위해서는 압전웨이퍼의 탐지범위 예측이 필요하다. 고주파수 대역에서 압전웨이퍼의 탐지범위에 영향을 주는 여러 가지 요인 중 가장 지배적인 인자는 보의 감쇠이다. 이 연구에서는 보에 부착된 압전웨이퍼의 전기역학적 신호를 이용하여 보의 감쇠를 추정할 수 있는 기법을 제시한다. 공진이 발생하는 과정에서 보의 감쇠효과를 고려하여 압전웨이퍼의 전기역학적 신호를 파전달 관점에서 정식화한다. 실제 계측된 전기역학적 신호로부터 구한 측정 감쇠비 함수값과 정식화된 전기역학적 신호로부터 계산된 감쇠비 함수값의 차이를 최소화하는 최소자승법을 통해 보의 감쇠비를 추정한다. 제시된 방법을 압전웨이퍼가 병치되어 있는 알루미늄 보 수치 및 실험 예제에 적용하여 타당성을 검증한다.

Keywords

References

  1. Alleyne, D. and Cawley, P. (1992). "The interaction of Lamb waves with defects." IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, Vol. 39, pp. 381-397. https://doi.org/10.1109/58.143172
  2. An, Y. K. and Sohn, H. (2012). "Integrated impedance and guided wave based damage detection." Mechanical Systems and Signal Processing, Vol. 28, pp. 50-62. https://doi.org/10.1016/j.ymssp.2011.11.016
  3. Annamdas, V. G. M. and Soh, C. K. (2010). "Application of electromechanical impedance technique for engineering structures: review and future issues." Journal of Intelligent Material Systems and Structures, Vol. 21, No. 1, pp. 41-59. https://doi.org/10.1177/1045389X09352816
  4. Chopra, A. K. (2001). Dynamics of structures 2nd edition. Prentice Hall, Upper Saddle River, NJ.
  5. Crawley, E. F. and De Luis, J. (1987). "Use of piezoelectric actuators as elements of intelligent structures." AIAA Journal Vol. 25, pp. 1373-1385. https://doi.org/10.2514/3.9792
  6. Fahy, F. J. and Gardonio, P. (2007). Sound and structural vibration: radiation, transmission and response. Academic press.
  7. Fung, Y. C. (1965). Foundation of solid mechanics. Prentice-Hall, Englewood Cliffs, NJ.
  8. Graff, K. F. (1991). Wave motion in elastic solids. Dover Publications, New York, NY.
  9. Hu, Y. and Yang, Y. (2007). "Wave propagation modeling of the PZT sensing region for structural health monitoring." Smart Materials and Structures, Vol. 16, No. 3, pp. 706-716. https://doi.org/10.1088/0964-1726/16/3/018
  10. Ikeda, T. (1990). Fundamentals of Piezoelectricity. Oxford University Press, New York, NY.
  11. Lim, Y. Y. and Soh, C. K. (2014). "Towards more accurate numerical modeling of impedance based high frequency harmonic vibration." Smart Materials and Structures, Vol. 23, No. 3.
  12. Mei, C. and Mace, B. R. (2005). "Wave reflection and transmission in Timoshenko beams and wave analysis of Timoshenko beam structures." Journal of Vibration and Acoustics, Vol. 127, pp. 382-394. https://doi.org/10.1115/1.1924647
  13. Park, G., Sohn, H., Farrar, C. R. and Inman, D. J. (2003). "Overview of piezoelectric impedance-based health monitoring and path forward." The Shock and Vibration Digest, Vol. 35, pp. 451-463. https://doi.org/10.1177/05831024030356001
  14. Park, H. W. (2014). "Understanding the electromechanical admittance of piezoelectric transducers collocated on a finite beam from the perspective of wave propagation." Journal of Intelligent Material Systems and Structures, Vol. 25, No. 17, pp. 2122-2140. https://doi.org/10.1177/1045389X14549874
  15. Park, H. W. (2016). "Evolution of electromechanical admittance of piezoelectric transducers on a Timoshenko beam from wave propagation perspective." Journal of Intelligent Material Systems and Structures, in press.
  16. Park, H. W., Lim, K. L., Kim, E. J. and Sohn, H. (2010). "Spectral element formulation for dynamic analysis of a coupled piezoelectric wafer and beam system." Computers & Structures, Vol. 88, No. 9-10, pp. 567-580. https://doi.org/10.1016/j.compstruc.2010.01.010
  17. Piezo Systems, Inc. (2016). PSI-5A4E piezoelectric sheets and their properties. Available at: http://www.piezo.com/prodsheet1sq5A.html (accessed 25 November 2016).
  18. Raghavan, A. and Cesnik, C. E. S. (2007). "Review of guided-wave structural health monitoring." The Shock and Vibration Digest, Vol. 39, pp. 91-114. https://doi.org/10.1177/0583102406075428
  19. Rose, J. L. (1999). Ultrasonic Waves in Solid Media. Cambridge University Press, New York, NY.