Joled

Abstract

We present JOLED, a mid-air display for interactive physical visualization using Janus objects as physical voxels. The Janus objects have special surfaces that have two or more asymmetric physical properties at different areas. In JOLED, they are levitated in mid-air and controllably rotated to reveal their different physical properties. We made voxels by coating the hemispheres of expanded polystyrene beads with different materials, and applied a thin patch of titanium dioxide to induce electrostatic charge on them. Transparent indium tin oxide electrodes are used around the levitation volume to create a tailored electric field to control the orientation of the voxels. We propose a novel method to control the angular position of individual voxels in a grid using electrostatic rotation and their 3D position using acoustic levitation. We present a display in which voxels can be flipped independently, and two mid-air physical games with a voxel as the playable character that moves in 3D across other physical structures and rotates to reflect its status in the games. We demonstrate a voxel update speed of 37.8 ms/flip, which is video-rate.

Point-and-Shake

“…The state-of-the-art has recently been advanced to allow multiple levitated objects to be moved independently of each other [17], to allow objects to be rotated [14,20], and to allow levitation over a single array [14]. We use an acoustic levitation system in our research because the ability to position and move multiple objects allows for richer interactions than the other methods currently do, although the interactions we develop are not limited to this approach.…”

“…Two ways of doing this are to manipulate an object's position or appearance. ZeroN [13] used projectors to augment objects and JOLED [20] rotated the objects, which were coloured differently on each side. Instead, we take the first approach: manipulating the object position.…”

“…In an acoustic levitation system, objects must be at least λ 2 apart [20], which is approximately 4.3mm for the 40 kHz ultrasound used in our system and in the stateof-the-art. Additional space is required for object movement, therefore increasing object spacing.…”

“…Acoustic levitation, in particular, has benefited from recent work [14,15,17,20] and many objects can now be levitated and moved independently. Research is now required to establish the interaction techniques needed to manipulate such displays.…”

Levitating Particle Displays with Interactive Voxels

“…Presenting 'meals' in this way altered the perception of taste and demonstrated a novel way of including taste in interaction. Acoustic levitation can also be enhanced with other objects placed around or amongst the levitating particles [23], so long as they do not reflect sound. Other research has used coloured particles [22,23] and particles physically joined by string [22] to further enhance the display capability.…”