Feasibility analysis of using piezoceramic transducers for cantilever beam modal testing

This paper presents a theoretical analysis of the application of piezoceramic transducers to cantilever beam modal testing. Four pairs of sensors and actuators, including accelerometer - point force, accelerometer - PZT, PVDF - point force and PVDF - PZT, are considered. The frequency response functions (FRFs) for the four pairs of sensors and actuators are first derived and written in the conventional modal format. The characteristics of modal parameters can thus be interpreted through the FRFs. A column of the FRF matrix can then be obtained based on the theoretical formulation. A curve-fitting algorithm is then applied to extract the modal parameters, such as natural frequencies, mode shapes and damping ratios. Results show that any sensor - actuator pair can successfully determine natural frequencies and damping ratios. Point types of transducer result in the displacement mode shapes, while piezoceramic transducers that are strip types and distributed in sense give the mode shapes of the slope difference between the edges of piezoceramic transducers. The paper provides the theoretical basis of applying piezoceramic transducers to experimental modal analysis and numerically supports the feasibility of cantilever beam modal testing using piezoceramic transducers.