Swimmer with submerged SiO2/Al/LiNbO3 surface acoustic wave propulsion system

Abstract

Acoustic propulsion system presents a novel underwater propulsion approach in small scale swimmer. This study introduces a submerged surface acoustic wave (SAW) propulsion system based on the SiO2/Al/LiNbO 3 structure. At 19.25 MHz, the SAW propulsion system is proposed and investigated by the propulsion force calculation, PIV measurements and propulsion measurements. 3.3 mN propulsion force is measured at 27.6 Vpp. To evaluate the miniature swimmer, the SAW propulsion systems with multiple frequencies are studied. At 2.2 W, the submerged SAW propulsion system at 38.45 MHz demonstrates 0.83 mN/mm2 propulsion characteristics. At 96.13 MHz and 24 Vpp, the movements of miniature swimmer with a fully submerged SAW propulsion system are recorded and analyzed to a maximum of 177 mm/s. Because of miniaturization, high power density, and simple structure, the SAW propulsion system can be expected for some microrobot applications, such as underwater drone, pipeline robot and intravascular robot.