From Clicks to Touches: Enabling Face-to-Face Shared Interfaces
The term display suggests a device used solely to output visual information, untouched for fear of occluding or dirtying the screen. Surfaces, meanwhile, are free of this burden – they are a part of the physical environment, and invite both touching and interaction. What happens, then, when surfaces become displays and when input and visual output spaces are superimposed, creating touchable,interactive surfaces? Such surfaces can be used in any number of ways; one exciting form-factor is as a horizontal, interactive, computationally augmented tabletop. Interactive tables provide three potential benefits for users over traditional displays: First, since a direct touch interactive table serves both as a display and as the user’s immediate direct input device, natural hand gestures and intuitive manipulations may be employed to improve the fluidity and reduce the cognitive load of interaction between the user and the digital content. Second, by leveraging the tendency to gather around a table for face-to-face interaction, a horizontal tabletop surface offers affordances and opportunities for building and enhancing co-located collaborative environments. Third, large surfaces such as tabletops offer a spacious work area that may influence working styles and group dynamics. The larger area also provides a larger visual field, which may be utilized as external physical memory in order to extend the working memory capacity of its users, and as an external cognitive medium.
In the past few years, in our pursuit to exploit the advantages and the affordances of direct-touch surfaces, we have designed, implemented and studied a variety of tabletop user interfaces, interaction techniques, and usage scenarios. We have also carried out empirical evaluations, and obtained preliminary findings on how people using a story-sharing table with digital photos, on non-speech audio feedback on multi-user interactive tabletops, and on some of the effects of the size of groups on different aspects of multi-user tabletop collaboration. In this talk, I will describe six particular challenges for the design of direct-touch tabletop environments, and present solutions and experiences to these challenges.