Tangible Intermediaries
The tangible intermediary is an idiom for the design of user interfaces that places the focus on augmenting existing physical objects with cast computation. We applied this notion as a design principle to the implementation of Golly, an augmented reality go board game. Golly augments a physical go board by fluidly integrating many of the computational enhancements previously only available with graphical user interfaces. After running an experiment to compare Golly to traditional graphical user interfaces we found that participants could interact with it more quickly. Additionally, we found that participants preferred Golly to traditional designs. It is our conjecture that the participants' preference for and increased performance using Golly are due to the ease with which users can learn interfaces based on the tangible intermediary idiom. Tangible Intermediaries represent an important direction both for user interface designers, and for projector manufacturers.
Background & Objective: Tangible intermediaries represent a step in an interesting direction for ubiquitous computing. Tangible intermediaries are a way to layer computation onto existing objects: without replacing them, or adding LCD panels with GUI interfaces, or requiring a separate handheld for configuration. The user can interact with objects in their environment exactly the same way as they always have, but the computer can now sense those interactions, and can supply helpful feedback as an overlay, or take complementary actions. Golly is a tangible intermediary for the game of go. Using vision techniques, an unmodified go board can be observed and gameplay recorded and analyzed. Making use of an LCD projector, the board can be augmented with information from the computer, for instance, by projecting a remote opponent's moves onto the board, displaying a clock to show how much time has elapsed during the user's move, or allowing users to back off several moves and explore variations.
Technical Discussion: The playing surface is a common table viewed by a Firewire camera and illuminated with an LCD projector from overhead. The perceptual system is implemented primarily in Java, supported by assembly-coded image manipulation functions. The system runs on two Intel 1GHz workstations: one to process the firewire camera data, and a second to manage the display projector. The overall goal of the perceptual system is to understand the progress of the game well enough to support the interaction modalities discussed above.
Technology Areas:
Off the Desktop Interaction and Display
Computer Vision
Modification Date: November 18, 2008