Micro motion of a piezoelectric linear actuator driven by liquid interacting with Rayleigh surface acoustic wave

Abstract

The research work presents a newly developed mechanism using liquid for surface acoustic wave (SAW) actuator making linear motion resulting in a no-load lightweight design. The proposed actuator consists of Interdigital Transducers (IDTs) fabricated on two ends of lithium niobate (LiNbO3) substrate and a cylindrical slider placed over the surface of the substrate in contact with liquid. The actuator uses Rayleigh wave traveling on the surface of the piezoelectric stators that transmit into a liquid medium which drives a cylindrical slider in translational motion. As the slider is not placed directly in contact with the stator, so the damage of piezo substrate or slider due to direct frictional contact is avoided. Due to this advantage, the longevity of the device will be enhanced and the driving load becomes easier. The movement of the slider on the liquid surface can be made to move in reverse direction by energizing the IDTs fabricated on other side of the substrate. The finite element simulation of the proposed SAW actuator and the experimental results demonstrates the slider reaches a steady-state velocity of 37.5 mm/s for application of wave excitation.