Application of continuous wavelet transform to detect damage in thin-walled beams coupled in bending and torsion

Abstract

The application of continuous wavelet transform to detect damage in thin-walled beams coupled in bending and torsion is presented. Damage is modeled as notch, crack, or decrease in modulus of elasticity and the wavelet coefficients that are functions of scale and translation parameters are plotted for different scales to seel sharp changes. The extent of damage can be estimated once the damage location is determined for the magnitudeds of wavelet coefficients that is proportioal to the loss of resistance. The results show that the mode shape derived from properly selected transducer distance will enable the wavelet coefficients with maximum amplitute so that the location and extent of damage can be effectively evaluated.