Range

An important challenge in designing ubiquitous computing experiences is negotiating transitions between explicit and implicit interaction, such as how and when to provide users with notifications. While the paradigm of implicit interaction has important benefits, it is also susceptible to difficulties with hidden modes, unexpected action, and misunderstood intent. To address these issues, this work presents a framework for implicit interaction and applies it to the design of an interactive whiteboard application called Range. Range is a public interactive whiteboard designed to support co-located, ad-hoc meetings. It employs proximity sensing capability to proactively transition between display and authoring modes, to clear space for writing, and to cluster ink strokes. We show how the implicit interaction techniques of user reflection (how systems indicate to users what they perceive or infer), system demonstration (how systems indicate what they are doing), and override (how users can interrupt or stop a proactive system action) can prevent, mitigate, and correct errors in the whiteboard's proactive behaviors. These techniques can be generalized to improve the designs of a wide array of ubiquitous computing experiences.