Research on a new type of ultrasonic bearing based on near field acoustic levitation

In this paper proposed an air bearing based on the mechanism of NFAL can levitate and position objects due to both a vibrating cylindrical stator and two circular plates. A group of piezoelectric ceramics is bonded on the cylindrical stator surface to acquire the standing wave bending vibration and resulting acoustic levitation, which provides radial non-contact support, and the two circular actuators bonded at both ends of the housing can also respectively be piezoelectrically excited standing waves to provide an axial position support. Structural dynamics analysis and simulation is carried out for the stators to select appropriate materials and modals. Finally, a prototype is manufactured, and the modal parameters and the levitation ability of the proposed bearing are measured. By means of simulation and experimental results a non-contact levitation bearings with considerable bearing capacity and a simple system structure can be achieved based on NFAL mechanism.