Rendering Physical Effects In Tabletop Controls

We introduce dynamic physical properties as an additional degree of freedom for passive tabletop controls. Using electromagnetic actuation, we manipulate attributes of tangibles on the fly, such as perceived weight, spring resistance, friction, and latching. We describe our actuation concepts, prototypes, and measurements showing that magnetic fields can change physical effects in a linear way. Controlled experiments reveal that participants can tactually distinguish four rendered resistance levels of a button prototype and easily detect dynamic detents in a continuous slider. Finally, we describe how adjustable physical properties in tangibles can enhance tabletop interaction.