Development of a Charge Estimator for Piezoelectric Actuators: A Radial Basis Function Approach

Development of a Charge Estimator for Piezoelectric Actuators: A Radial Basis Function Approach

Morteza Mohammadzaheri, Mohammadreza Emadi, Mojtaba Ghodsi, Issam M. Bahadur, Musaab Zarog, Ashraf Saleem
DOI: 10.4018/IJAIML.2020010103
Article PDF Download
Open access articles are freely available for download


Charge of a piezoelectric actuator is proportional to its displacement for a wide area of operating. Hence, a charge estimator can estimate displacement for such actuators. However, existing charge estimators take a sizable portion of the excitation voltage, i.e. voltage drop. Digital charge estimators have presented the smallest voltage drop. This article first investigates digital charge estimators and suggests a design guideline to (i) maximise accuracy and (ii) minimise the voltage drop. Digital charge estimators have a sensing resistor; an estimator with a constant resistance is shown to violate the design guideline; while, all existing digital charge estimators use one or a few intuitively chosen resistors. That is, existing estimators witness unnecessarily large inaccuracy and/or voltage drop. This research develops charge estimators with varying resistors, fulfilling the design guideline. Several methods are tested to estimates the sensing resistance based on operating conditions, and radial basis function networks models excel in terms of accuracy.
Article Preview

Digital Charge Estimators

Figure 1 is a schematic of a digital charge estimator, used in this research. The estimator comprises of (i) a digital part, within the computer, (ii) an I/O card including analogue to digital (A/D) and digital to analogue (A/D) units, and (iii) analogue parts including the actuator, a voltage amplifier and a sensing resistor.

Figure 1.

A schematic of the experimental setup used in this research


VS, the voltage across the sensing resistor, is called the ‘sensing voltage’. VS is almost proportional to the current passing the actuator, iP, and most of iP passes through the grounded sensing resistor, RS:

Complete Article List

Search this Journal:
Volume 13: 1 Issue (2024)
Volume 12: 2 Issues (2022)
Volume 11: 2 Issues (2021)
Volume 10: 2 Issues (2020)
Volume 9: 2 Issues (2019)
View Complete Journal Contents Listing