Shared Design Space
Collaborative Augmented Reality setups are becoming increasingly popular. Instead of using head mounted displays (HMDs), we have developed the Shared Design Space, a collaborative tabletop environment that is designed for brainstorming and discussion meetings. Using a digital pen, participants can annotate not only virtual paper, but also real printouts. By integrating both forms of physical and digital paper, we combine virtual and real 2d drawings, 3d models, and digital data which are overlaid into a single information space. We have integrated these devices together in a unique way and present an application where they can be used efficiently during a design process.
The Shared Design Space combines a number of diverse technologies to create a unique interface, including:
- a vertical touch sensitive rear-projection surface,
- a large horizontal tabletop projection setup,
- Anoto digital pens and paper,
- integration of multiple devices (laptop, tablet PCs, etc.),
- a wireless networking setup, and the
- combination and integration of different interaction metaphors (e.g. advanced hyper-dragging, Pick&Drop, and intuitive interaction with both the table and rear-projection surface).
Each of these elements is not unique in itself, but this project combines them in a unique way to create a new collaborative interface.
The setup is based on a pattern, which is tracked by the digital pens. Anoto-based pens are ballpoint-pens with an embedded camera that tracks the movements simultaneously. The pen has to be used on a specially printed paper with a pattern of tiny dots. Each paper sheet is unique and can be ordered from Anoto. In our setup, we use this technology in two ways. Firstly, to track the whole table surface and secondly to combine real paper with digital augmented content. All pens – with their inbuilt infrared camera track at least 36 dots of the paper to retrieve both the ID of the paper and the position relative to the upper left corner of the paper. The position can then be sent in real-time to the PC via Bluetooth. Currently, three commercial pens with Bluetooth are available from Nokia (SU-1B), Logitech (io-2), and Maxell (PenIT).
36 tiny dots are arranged on a square area of 1.5 x 1.5 mm2. The Anoto pattern, placed under the Plexiglas, allows accurate tracking of digital data and the projected content does not interfere with the tracking of the digital pen.
Pick and Drop
In our setup, users can pick-up digital data from the table (e.g. video, image) and drop-it on the real paper by using the digtial pen. Once the user taps a digital object on the interactive table, the content manager automatically binds it (virtually) to the pen. Whenever the user moves the same pen onto the real paper, the manager transfers the data to the server that displays it on the interactive table.
This interface allows users to easily explore design options in a creative context through an intuitive interface of real and virtual artist and designer tools. Using computers in a face-to-face meeting can disrupt the creative process because communication cues cannot be shared as easily as in natural face-to-face conversation. The Shared Design Space allows people to communicate as they normally would around a table and enhances this communication with intuitive collaborative tools. This work points to a future where computers will be able to naturally support face-to-face meetings and creative design sessions.
For the Interactive Wall setup we use a 60” diffuse Plexiglas display surface with special qualities for rear-projection. The anti-reflex surface homogeneously distributes the light to achieve a balanced image. A single camera tracking solution provides the interaction data for the document presentation. An IR pass filter that is applied to the camera avoids interferences with the projected image. As the tracking is done via shadows in the IR spectrum, IR lights are needed to provide a homogneous illumination in front of the screen.
Touching the screen with one hand, the user can scroll through the documents. A timeline on top provides a map-like overview that can also be used to navigate in a fast-forward style. Using both hands activates the zoom mode on screen, changing the distance between the hands affects the zoom-level accordingly.