Using an ultrasound speaker, we have developed a self-made device for acoustic levitation. The goal is to use this device to develop a new media that enables new visual expression. By using ultrasonic waves emitted from a speaker to generate standing waves, we are able to levitate polystyrene particles. The standing waves could also be visualized by using dry ice.
While there have been previous visual experience technologies using ultrasound for haptic presentation, recent research has shown that ultrasonic levitation can also be used for new graphic expression, such as drawing graphics in the air. We started our research based on the idea that it would be possible to give interaction to the graphics produced by such technologies and to create a new media for visual expression. By starting this research, we decided to build our own low-cost acoustic levitation device, and to develop a new media by making improvements to it.
Components Of Device
This ultrasonic levitation device has ultrasonic speakers that emit a resonant frequency of 40 kHz attached to a plastic sphere. Fifty ultrasonic speakers are installed to output ultrasonic plane waves toward the center of the plastic sphere. This makes it possible to focus the ultrasonic waves at the center of the plastic sphere and to obtain the sound pressure necessary for levitation. In order to keep the two ultrasonic devices facing each other stable and upright, a neodymium magnet is attached to this device and fixed to the bookends.
We aim to achieve real-world aerial image expression on a pixel-by-pixel basis through pinpoint projection onto floating beads. We also hope to realize an interface that enables interaction with floating objects, and to make it possible to enrich video expression through some influence on the projected images by the floating objects.
This work was partially supported by the Japan Society for the Promotion of Science KAKENHI Grant Number 21K12004.