A miniature rod-type rotational piezoelectric motor

This paper presents the design of a miniature rod-type high rotational speed piezoelectric motor for application in micro air vehicles. The motor is consisted of a rod-type stator with a flexible support, piezoelectric ceramic sheets, conical rotor, rotating shaft, bearing, shim, spring and retaining bolts. Four piezoelectric ceramic sheets, arranged in pairs opposing each other to form two phases with reversed polarization directions, invoke the rotor's rotational motion via excitation two bending modes of the stator. Evaluate mechanical properties of the prototype, the stator weighs 2.5 g, its operating frequencies is in the range of 53.62-54.06 kHz. Under the preload force of 0.4 N and voltage of 250 Vp-p, prototype achieved rotational speeds up to 3800 rpm and output torque is 0.36 mN·m, capable of generating lift force of 1.3 g. This piezoelectric motor provides a foundational study for potential applications in micro air vehicles and other domains.