ERCIM News No.44 - January 2001 [contents]

The Pond: Trawling the Information Sea

by Lennart E. Fahlén, Jan Humble, Olov Ståhl, Jonas Söderberg and Anders Wallberg

The Pond is a desk-projection based system for search, visualization and transactions of data elements stored in local databases or on the Internet. Based on a 3D ecosystem metaphor, the Pond approach for querying, presenting and manipulating data elements differs considerably from more conventional information systems. 

Conventional data search engines (eg Internet search tools such as AltaVista , Yahoo and products such as Oracle DBMS) mostly provide textual representations of results, and are thereby somewhat limited to 2-dimensional layout. 3D data visualization systems such as VR-VIBE from Nottingham University and Q-PIT developed at Lancaster University show some promise in building a general overview, but require prior knowledge of the system in order to interact and especially navigate.

The ICE laboratory at SICS experiments with new approaches to information presentation and manipulation. As part of this effort the Pond has been developed. The Pond is an information system based on an ecosystem metaphor allowing users to search for data elements stored in local databases or the Internet, and present the results as flocks of aquatic entities inside a 3D virtual pond. The key element in the interface is the information carrying entities’ ability to make their presence known and adapt their behaviour based on how they are handled, such as acquiring or relinquishing interest towards user presence.

The design is that of a desk-based projection system, a table around which users gather to perform queries and interact with the resulting pond flocks. The back-projected tabletop surface is touch-sensitive, allowing for direct interaction with the pond environment (see Figure).

Users perform queries by using credit card sized tags associated with specific keywords that are matched against data stored in a database or on an Internet site. A number of tag readers have been incorporated into the Pond tabletop, and users need only place keyword tags (eg The Beatles or ‘techno’) on one of these to initiate a search. Once the search results have been retrieved, a flock of pond creatures representing the query result is created and inserted into the virtual pond environment, where the flock starts to move around and respond to user manipulations.

Entity Flocks
Each member of the flock has an autonomous behaviour, controlled by a number of simple navigational rules which, when combined, gives the flock a lifelike behaviour. For instance, entities within a specific flock try to stay together and avoid members of other flocks. This allows for easily identifiable result groupings, even long after the flock was created and with the environment vastly populated. The flocks also have a ‘garbage collection’ behavior that helps to ensure that the pond will not be cluttered with old or uninteresting information. As more and more flocks are added, older flocks that haven’t been manipulated for some time will automatically sink towards the bottom of the Pond, and eventually be removed. However, users are able to ‘revive’ a sinking flock by interacting with it, in which case the flock will return to the surface.

Accessing Information
Each flock member represents some information element that is the result of a database query. Users are able to access this information by manipulating the entities in different ways. In the current version of the Pond, entities represent consumer audio items (eg CDs, MiniDiscs, cassettes etc.), which means that there are two types of information available for each entities, the record data (eg, artist and album title), and the audio data itself. Entities in the Pond are easily identifiable because they are texture mapped with the cover image from the album they represent.

By tapping on an entity (ie touching the display surface), a user selects an entity and is then able to see information identifying the artist and album title for the corresponding record. This information is attached to the 3D entity object, moving alongside it and is only visible for a short while.

Tapping on a creature that is already selected activates playback of audio samples from the corresponding album. When this happens the entity will float to the surface making it easy to identify the record being played. A text will also appear inside the pond, stating the record name, artist and title of the track being played. By repeated tapping on a entity currently being played, users are able to step through the audio clips available for the album. Once a track has been played the entity will swim away from the surface and return to its flock.

Building a Selection
Users can gather entities in creels, specific areas of the pond environment placed close to the tag readers. Once inside the creel, an entity is constrained to move only within the creel boundaries and a new flock is automatically generated, contextually related to the gathered selection(s). Placing a recordable-type tag on the reader reintroduces the entities previously stored on that tag (if any), merging them with the existing selection in the creel. The link between a recordable-tag and selected entities within a creel is created when the tag is removed from the reader, at which point the creel flock will also be removed from the pond environment.

The audio environment of the Pond consists of both ambient and feedback style sounds. Since the metaphor is that of a pond or pool of information, the soundscape consists of a family of aquatic, bubbling, splashing and whirling sounds, giving the impression of the data elements ascending from an abyss of ooze or mud. The ambient sounds fade out when a chosen music sample is played, and fades smoothly back in when the music stops. The interface sounds indicate various actions taken by the users, for instance placing tags on a reader, dragging entities, etc.

The Pond is a tool for exploring database results in an appealing and inviting fashion, encouraging a collaborative space. Based on flocking algorithms to group data and direct user manipulation via a touch sensitive display, the Pond investigates alternative interfaces to databases, information and transactions systems. The Pond is an example of an Electronic Landscape Artifact developed within the eScape - Esprit long term research project 25377 and the Swedish Research Institute for Information Technology (SITI) Internet3 project ELP.

The Pond project:

Please contact:
Lennart E. Fahlén - SICS
Tel: +46 8 633 15 39