Bird-like flight in a spatialised, navigable musical environment
Flying like a bird. It's something every child and most adults would like to do, and something that Driftnet, an interactive visual and aural exhibit, lets us do. Driftnet is the combination of two ideas: bird-like flight and a spatial, visual, navigable musical environment.
Driftnet was created by Squidsoup, a not-for-profit interactive arts company. The project was partly developed during a Research Fellowship at Arts Institute Bournemouth in the United Kingdom. Participants in the interactive exhibit are equipped with 3D glasses and invited to navigate the virtual space by "flying like a bird". The mechanics of bird flight were simplified to movements such as flapping both arms to go forward and tilting outstretched arms to turn left and right.
Simply body movements control the flight path
To control a 3D viewpoint using flying motions, Anthony Rowe, Founder of Squidsoup and lead artist, used a Bumblebee2 stereo camera from Point Grey Research. "Whole body interactions is one of the research topics we are working on, and cameras make excellent input devices for this." says Rowe. "We originally started using simple webcams, then moved on to using the Bumblebee2, which produced depth map information of sufficient accuracy to be used as the basis for interaction detection in 3 dimensions."
Bumblebee2 depth maps provide 3D interaction detection
Driftnet uses depth image information from an overhead-mounted Bumblebee2 camera, shown in the figure below. The mechanics of bird flight were abstracted to a simple class of flight modes, mainly because users have very different ideas about how a bird will perform certain tasks (e.g. breaking, ascending and descending), and also out of an artistic desire for users to focus on the experience rather than the process of flying.
Driftnet technical configuration, with overhead-mounted Bumblebee2
The final project comprised three connected virtual spaces, each with its own set of sonic agents and behaviours. Two of the spaces have no up or down, and the third consists of a dynamic surface. They are visualized using anaglyphic stereoscopy (red/cyan specs) to enhance the feeling of depth and immersion (and also an interesting parallel to the stereo camera input).
Visualizing space using anaglyphic stereoscopy (red/cyan specs)
The piece was first tested for six nights at Shunt, a club in London Bridge (London, UK). "It worked well, and people really seemed to enjoy it," comments Rowe. Laughing, he adds, "The only issue was that despite the instructions clearly asking people to 'fly', as the evenings wore on people tried swimming, break-dancing and performing alcohol-induced falling-over movements…"
During their initial search for a stereo camera, Rowe and his colleagues considered several alternatives before choosing to evaluate a Bumblebee2. Critical factors included cost, stereo imaging quality, and application support during the development process.
"Technologies like the Bumblebee2 are an ideal choice for anyone looking for new ways to engage the public in interacting with digital experiences," says Rowe. "In busy public spaces, digital imaging techniques are a very effective form of interface. They are more reliable and flexible than physical input devices, can be placed out of reach, and allow participants completely free and uninhibited movement. And with depth map imagery, subtler forms of 3D interaction are possible."
The Arts Institute at Bournemouth, UK