Design and Investigation of a Dual Friction-Drive-Based LiNbO3 Piezoelectric Actuator Employing a Cylindrical Shaft as Slider

摘要

This research work presents the design and investigation of a surface acoustic wave (SAW) actuator based on dual friction-drive (DFD) technique employing a cylindrical shaft as a slider. The proposed SAW actuator made of a cylindrical shaft located between two alike piezoelectric stators in the mirror image approach. The stator is made up of interdigital transducers (IDT) fabricated on the surface of a lithium niobate (LiNbO3) piezoelectric substrate at either side of it, known as a delay line. By providing the appropriate potential to the IDTs, produce Rayleigh SAW on the stator surface. The cylindrical shaft is placed on the working area of the delay line of both the stators, while an ample preload is applied to the assembly for the friction-drive. The generated SAW along with the applied load makes interaction with the shaft and the resulted force due to friction drives the shaft. A concurrent excitation to the both IDTs, present at a single side of the actuator, one each from the bottom and the top stators, the cylindrical shaft makes a translational motion towards the side of excited IDTs. Experimental setup of the DFD SAW actuator demonstrates that the shaft can attain a steady velocity of 1.9 m/s for the application of a continuous SAW excitation of a frequency of 13.5 MHz with an optimal preload condition.