A Low Cost Experimental Set-up to Characterize Piezoelectric Cantilever Bimorphs

Hysteresis is a common phenomenon in nonlinear systems. Piezoelectric bimorphs show hysteretic behavior, when operating as actuators. Tools producing the characterization of these devices are available, which use high cost set-up measuring deformations with resolutions in the order of 10^-3 mum. In this paper, a new low cost experimental set-up for investigating the behavior of piezoelectric actuators is discussed, which uses coupled infrared detectors. The tool, providing deformation measurements with a resolution in the order of 10 mum, is intended to produce a rough estimation of the device behavior, which would be of interest for research and educational purposes. Low cost, easy reproducibility in research laboratories and educational laboratories, contact-less measurement strategy, inset calibration facility and suitable user interface are the main features of the tool developed. Notes on the uncertainty introduced by the tool when estimating the bimorph deformation are given. Moreover, a case study concerning the characterization of a piezoelectric bimorph actuator is discussed to illustrate the performances of the system developed in a real case