Extended Morlet-Wave damping identification method

This paper deals with the identification of the damping which is one of the important structure properties that involve phenomena with different origins such as internal friction on the level of crystals in materials, friction at joints and interfaces, fluid flow, etc. Detection of damping ratio is very sensitive for the identification due to the various influences on the measured signals that causes errors. It is important to have a method that will identify it with high accuracy regardless of the errors in signal. An existing method Morlet Wave damping identification (MWdi) proven to be highly resistant to errors in signal but very sensitive to change of the identification parameters. Solution to this issue is presented in this paper. The MWdi method is upgraded by proposing a parameter selection strategy. Strategy is based on identification of damping ratio for the whole range of feasible identification parameters by searching for the lowest variation of the identified value. The Extended MWdi method (EMWdi) is tested on the numerically simulated impulse response functions (IRF) and on the experimentally measured IRFs. In both cases, the results of the identified damping ratios are compared to the damping identification method using the continuous wavelet transform (CWT).