Dynamic Response of Circular Shaft with Piezoelectric Sensor

Abstract

The dynamic behavior of a circular shaft with piezoelectric sensors under torsion was studied analytically and experimentally. The system equations were derived from the mechani cal properties of the shaft and the electroelastic behavior of the piezoelectric material. These equa tions were converted into a set of matrix equations using the finite element method. Since the dynamic response of the circular shaft was coupled with a small fraction of its bending modes during torsional vibration, both axisymmetric torsional and bending elements were used in the finite ele ment method. The sensor equation of the piezoelectric film was derived from its constitutive laws by rotating the film an angle with the shaft axis. The piezoelectric sensor was used to obtain frequency responses of the system. In the experiment, a circular shaft with three flywheels was built to examine its dynamic behavior. External excitation 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 analytical and experimental results.