To celebrate the exhibition The Future Starts Here, we have collaborated with Stamen Design to produce Big Glass Microphone – a data visualisation of a 5 kilometre long fibre optic cable buried under Stanford University.
The Stanford University fibre optic cable is used mostly for analysing seismic waves as they pass through the campus but Stamen are using it to discover more normal activities closer to home.
Vibrations caused by objects moving near fibre optic cables are usually considered undesirable and filtered out as noise but by turning that noise into a signal, Stamen can make inferences about the things that are near the cable, whether it's a bicycle moving down a road, a cow wandering around in a field or even water flowing from a fountain.
Using Distributed Acoustic Sensing technology from Optasense, a company that installs this technology along railroads, pipelines, and other infrastructure, Big Glass Microphone visualises the distinct shapes that different kinds of events have on this fascinating incidental listening device, that can be hundreds of kilometres long.
Big Glass Microphone is intended to evoke a sense of wonder about the kinds of detections and interactions that are increasingly common in our ubiquitously networked society. If a fibre optic cable buried in the ground can tell that you’re walking by, what can the telephone wires over your head tell? What kinds of artistic, urban, commercial, governmental possibilities await as more and more cable is laid to power, say, smart street lights?
Explore a wide spectrum of vibrations
Each horizontal band represents a different frequency of vibration: 0 – 0.6 Hz, 10 – 20 Hz and so on, up to 320 Hertz. The lowermost horizontal bands are sounds we can hear, and the uppermost bands are subsonic vibrations. The brighter the section of band, the more intense the vibration at that scale. You can explore different frequencies by clicking them on and off, on the right-hand side of the interactive.
Explore data in space and time
Different spatial and temporal aspects of the data can be explored by clicking and dragging your mouse over the time strip on the left-hand side of the interactive. You can discover cars driving along a road, with the electromagnetic impulses from their engines activating the cable.
Or we can infer a less activating kind of movement is probably a person or a bicycle.
And this vertical line marks the position of a fountain at Leland Stanford Jr University, which (when it's on) sends out a more or less constant vibration of between 160 – 300 Hz, a bit higher than a human voice.
