Design of A Short-beam Linear Traveling-wave Piezoelectric Motor.

A straight short-beam linear piezoelectric motor constructed with two sets of ceramic actuators separated with the 1/4 wavelength interval is designed in this article. The piezoelectric ceramic actuators are fabricated in the whole body, which is driven by a two-phase circuit with the same amplitude but phase difference of π/4. Traveling wave is formed by superimposing standing waves generated by each set of ceramic actuators. At the ends of the short beam, a wave-reduction mechanism with larger cross-section area is designed so that wave reflection is effectively diminished to preserve the traveling wave. The currently developed short-beam linear piezoelectric motor is estimated can produce an ideal output speed of 169mm/sec while applying voltage of Vpp=300V@45.49kHz. Instead of operating as a stator to drive a carriage for example, the short-beam linear piezoelectric motor is implemented on a guide slider, therefore a linear piezoelectric motor stage is built. While driving the linear stage employed with a preload 300gw and a friction coefficient of about 0.15, the propulsion force is measured about 4.8N, the speed is about 56mm/sec and the position resolution can achieve in the submicron scale.