Induced voltage in piezoelectric tube driven segments and their use in nanopositioning, an assessment

A piezoelectric tube actuator has a number of segments or electrodes. The induced voltage and the piezoelectric voltage, two easy-to-measure electrical signals in piezoelectric tubes, have been used in position estimation of these actuators since 2006 and 1982. However, since introduction, the induced voltage has never been compared with the piezoelectric voltage for piezoelectric tubes’ position estimation. In addition, only linear models have been used to present the relationship between the induced voltage and the position of piezoelectric tubes. In other words, in the literature, it has been practically assumed that (1) the relationship between the induced voltage and the position is linear, and (2) the induced voltage can estimate the position more accurately compared to the piezoelectric voltage. This article assesses and nullifies both these assumptions. In this research, with the use of the experimental data, both aforementioned voltage signals were mapped into the position through linear and nonlinear models. It was shown that the position can be estimated less accurately with the induced voltage compared to the piezoelectric voltage, and the relationship of the position with the induced voltage presents higher and non-negligible nonlinearity compared to the one with the piezoelectric voltage.