Direct identification of modal parameters using the continuous wavelet transform, case of forced vibration

  • Bedaoui, Safia (Laboratoire Navier (ENPC/IFSTTAR/CNRS), Ecole des ponts Paris Tech, Universite Paris Est) ;
  • Afra, Hamid (National Center for Studies and Building Research (CNERIB)) ;
  • Argoul, Pierre (Laboratoire Navier (ENPC/IFSTTAR/CNRS), Ecole des ponts Paris Tech, Universite Paris Est)
  • Received : 2012.12.30
  • Accepted : 2014.01.02
  • Published : 2014.04.30


In this paper, a direct identification of modal parameters using the continuous wavelet transform is proposed. The purpose of this method is to transform the differential equations of motion into a system of algebraic linear equations whose unknown coefficients are modal parameters. The efficiency of the present method is confirmed by numerical data, without and with noise contamination, simulated from a discrete forced system with four degrees-of-freedom (4DOF) proportionally damped.


modal identification;dynamics of structures;forced vibration;continuous wavelet transform


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