Tabletop Collaboration through Tangible Interactions

Recent advances in tracking technology have led to the design of digital tables that support interaction using multi- finger input and physical objects. However, the tradeoffs between these input modalities are not clear, making it difficult for developers to make informed decisions when choosing input strategies for digital table systems. In this paper, we consider the role that multi-finger input and physical objects play in the design of collaborative tabletop systems. We present the results of an observational study of group work on regular tables, and an experimental study of interaction techniques for supporting group handoff. Our results show that people often perform several explicit communication and coordination activities that involve epistemic and pragmatic movements of physical tools. Further, our experimental results suggest that using physical objects to control digital information improves performance over using finger gestures.