DYNAMIC-RESPONSE OF CIRCULAR SHAFT WITH PIEZOELECTRIC SENSOR

The dynamic behavior of a circular shaft with piezoelectric sensors un der torsion was studied analytically and experimentally. The system eq uations were derived from the mechanical properties of the shaft and t he electroelastic behavior of the piezoelectric material. These equati ons were converted into a set of matrix equations using the finite ele ment method. Since the dynamic response of the circular shaft was coup led with a small fraction of its bending modes during torsional vibrat ion, both axisymmetric torsional and bending elements were used in the finite element method. The sensor equation of the piezoelectric film was derived from its constitutive laws by rotating the film an angle w ith the shaft axis. The piezoelectric sensor was used to obtain freque ncy responses of the system. In the experiment, a circular shaft with three flywheels was built to examine its dynamic behavior. External ex citation was applied to the shaft using an impact hammer. The dynamic responses of the system were monitored by the potential differences of the piezoelectric sensor. Good agreement was obtained between the ana lytical and experimental results.