CRACK DIAGNOSIS IN PLATES USING PIEZO ACTUATED LAMB WAVES

This paper is a numerical simulation and verification of health monitoring of plate structures using propagating piezo-actuated lamb waves. The goal is to detect the location of a linear crack in a plate using piezoelectric actuator and sensor based on the time-of-flight of propagating lamb waves. The actuation signal is first determined based on the lamb wave modes for propagation in a thin plate and the group dispersion curve of an aluminum plate. The commercial finite element code (ABAQUS) has been employed to model a plate with an actuator-sensor pair and a tiny groove representing the crack. After a transient dynamic analysis, the sensor voltage has been acquired. Using Hilbert Huang Transform (HHT) method, from the time-energy spectrum of sensor response, location of the crack has been detected using propagating wave time-of-flight. A wavelet analysis has also been employed to validate HHT results.

کلیدواژه ها:

Piezoelectric ، Hilbert Huang Transform ، Wavelet ، Health Monitoring