Characterization of bulk piezoelectric element-based ultrasonic motors

Abstract

AbstractWe propose miniature ultrasonic motors using stators made of a single bulk piezoelectric element. The bulk piezoelectric stator has the potential to increase output by reducing the dissipation that occurs in the adhesion layer between the PZTs and a metallic component in the stator. In this paper, we build two kinds of bulk piezoelectric stators: a cubic bulk stator with a side length of 4.2 mm and a hole of 3 mm in diameter, and a cylindrical bulk stator with an outer diameter of 4.2 mm and the same hole diameter. We evaluate their electrical and mechanical characteristics, such as impedance and vibration velocity. The experiments clarify the advantages of the bulk piezoelectric stators, such as low dissipation. The cubic bulk stator, which shows higher performance than the cylindrical one, is compared with a similar-shaped stator using a bronze cube and thin piezoelectric plates. The performance measures of the cubic bulk ultrasonic motor are optimized by the preload between the stator and rotor.