Exploring tangible and direct touch interfaces for manipulating 2D and 3D information on a digital table

On traditional tables, people often manipulate a variety of physical objects, both 2D in nature (e.g., paper) and 3D in nature (e.g., books, pens, models, etc.). Current advances in hardware technology for tabletop displays introduce the possibility of mimicking these physical interactions through direct-touch or tangible user interfaces. While both promise intuitive physical interaction, they are rarely discussed in combination in the literature. In this paper, we present a study that explores the advantages and disadvantages of tangible and touch interfaces, specifically in relation to one another. We discuss our results in terms of how effective each technique was for accomplishing both a 3D object manipulation task and a 2D information visualization exploration task. Results suggest that people can more quickly move and rotate objects in 2D with our touch interaction, but more effectively navigate the visualization using tangible interaction. We discuss how our results can be used to inform future designs of tangible and touch interaction.