An admittance-based damage detection method with a higher-order circuit is proposed and investigated in this paper, in order to increase the damage detection sensitivity. The change of the stiffness in the structure due to the damages can be detected by measuring the admittance from the piezoelectric transducer adhered on the host structure. It is known that an inductive circuitry of an R-L-in-series branch serially connected with the piezoelectric transducer can introduce an additional resonance to the mechanical system. With the piezoelectric capacitance, it is a second-order circuit system with two resonances. In this research, based on the electrical-mechanical analogy, a higher-order circuit is designed to improve the damage detection capability, i.e., increasing the admittance magnitude and the admittance sensitivity magnitude. Theoretical analyses and simulations are carried out. The results show that the admittance magnitude and the admittance sensitivity are both significantly increased by using the higher-order circuit when comparing with the second-order circuit, both without electrical damping.

Date Published: 18 April 2012
PDF: 11 pages
Proc. SPIE 8348, Health Monitoring of Structural and Biological Systems 2012, 83480I (18 April 2012); doi: 10.1117/12.915570

Published in SPIE Proceedings Vol. 8348:
Health Monitoring of Structural and Biological Systems 2012
Tribikram Kundu, Editor(s)