Piezoelectric actuators are increasingly used in various nanopositioning applications and emerging applications where miniaturization is important. This is due to their unique characteristics including their very high accuracy and short response time as compared to electromagnetic based motors and actuators and higher output force compared to electrostatic actuators. Piezoelectric motors use actuators that take advantage of the converse piezoelectric effect. In this chapter, these motors are classified into quasistatic and ultrasonic motors (USMs) based on their working frequency. Several designs from the literature and commercial suppliers are reviewed and their characteristics are presented. Two examples of piezoelectric motors are discussed in detail. These include a piezoworm stage and a USM with segmented electrodes. Future development of these technologies is also briefly discussed addressing issues such as increasing the output power, the efficiency, and further miniaturization of these devices. |
