Abstract
This study concerns non-contact excitation of planer objects by using near-field acoustic levitation, in which a planer object having relatively large size and weight is levitated on a ultrasonic vibration plate with 10-100 μm air gap. This phenomenon has been studied as a non-contact transportation technology for a fragile thin plate such as flat panel display glass substrate. In this study, we investigate the possibility of this phenomenon as a technology for non-contact excitation of planer objects. In this paper, we propose a non-contact excitation method to vibrate the levitated object at arbitrary low frequency by modulating the ultrasonic amplitude of the vibration plate. An experimental study of non-contact excitation of plate specimens near the natural frequencies suggests that the system consisting of the vibration plate, the air gap, and the levitated plate can be modeled as a two-degree-of-freedom dynamical system.
