Enhancing Physical Objects with Actuated Levitating Particles

We describe a novel display concept where levitating particles are used to add a dynamic display element to static physical objects. The particles are actuated using ultrasound, for expressive output without mechanical constraints. We explore novel ways of using particles to add dynamic output to other objects, for new interactive experiences. We also discuss the practical challenges of combining these. This work shows how the unique capabilities of levitation can create novel displays by enhancing another form of media

Avoiding Collisions when Interacting with Levitating Particle Displays

Levitating particle displays are an emerging technology where content is composed of physical pixels. Unlike digital displays, manipulating the content is not straightforward because physical constraints affect the placement and movement of each particle: dragging a particle may cause it to collide with others along its movement path. We describe initial work into four new interaction techniques that allow users to avoid collisions when directly manipulating display content. Techniques such as these are required for interactive levitating displays to be practical when scaled up to large sizes

Levitation Simulator: Prototyping Ultrasonic Levitation Interfaces in Virtual Reality

We present the Levitation Simulator, a system that enables researchers and designers to iteratively develop and prototype levitation interface ideas in Virtual Reality. This includes user tests and formal experiments. We derive a model of the movement of a levitating particle in such an interface. Based on this, we develop an interactive simulation of the levitation interface in VR, which exhibits the dynamical properties of the real interface. The results of a Fitts' Law pointing study show that the Levitation Simulator enables performance, comparable to the real prototype. We developed the first two interactive games, dedicated for levitation interfaces: LeviShooter and BeadBounce, in the Levitation Simulator, and then implemented them on the real interface. Our results indicate that participants experienced similar levels of user engagement when playing the games, in the two environments. We share our Levitation Simulator as Open Source, thereby democratizing levitation research, without the need for a levitation apparatus.Comment: 12 pages, 14 figures, CHI'2

OpenMPD: A Low-Level Presentation Engine for Multimodal Particle-Based Displays

Phased arrays of transducers have been quickly evolving in terms of software and hardware with applications in haptics (acoustic vibrations), display (levitation), and audio. Most recently, Multimodal Particle-based Displays (MPDs) have even demonstrated volumetric content that can be seen, heard, and felt simultaneously, without additional instrumentation. However, current software tools only support individual modalities and they do not address the integration and exploitation of the multi-modal potential of MPDs. This is because there is no standardized presentation pipeline tackling the challenges related to presenting such kind of multi-modal content (e.g., multi-modal support, multi-rate synchronization at 10 KHz, visual rendering or synchronization and continuity). This article presents OpenMPD, a low-level presentation engine that deals with these challenges and allows structured exploitation of any type of MPD content (i.e., visual, tactile, audio). We characterize OpenMPD’s performance and illustrate how it can be integrated into higher-level development tools (i.e., Unity game engine). We then illustrate its ability to enable novel presentation capabilities, such as support of multiple MPD contents, dexterous manipulations of fast-moving particles, or novel swept-volume MPD content