A multi-transducer near field acoustic levitation system for noncontact transportation of large-sized planar objects

A new noncontact transportation system, which consists of multiple ultrason ic transducers and operates based on near-field acoustic levitation, is pro posed to transport a large-sized planar object such as a glass substrate fo r liquid crystal devices. Using the proposed systems consisting of two and three transducers, the suspension characteristics of the levitated objects are studied as functions of both size difference and angles between the vib ration systems and the levitated object. As a result, the holding force is proved to increase as the angle increases and is maximum when the horizonta l dimensions of the system and the object coincide.