Controlling the Human Pixel, with Light and Sound
Bluetooth, WiFi and cellular data may be nearly ubiquitous, but there are interesting edge cases where none of these channels will get the job done. One of those is the large music or sports event, where the event runner may want to broadcast some information to attendees’ mobile devices, in order to turn the attendees into pixels that make a light show of the entire arena.
In the old days, you’d just hope that everyone in the audience had a lighter, and then they’d all naturally start waving theirs around when the music got suitably epic. Today, the smartphone replaces the lighter. And the great thing about that, from a production standpoint, is that an event organizer can sidestep the messy job of instructing humans when to light their fire, or do the wave. They can control the device directly.
At SxSW I saw two companies bringing the you-are-the-light-show model to large venues. Both are fairly new and haven’t been used much lately, but you can expect to see them show up more.
First up: Sonic Notify. This company has a code library that can be embedded into a band’s or team’s smartphone app. The app listens for audio tones (in the 19 to 20 kHz range) and, when it hears the right noises, it can turn on the smartphone screen in whatever color the app asks for. Or do a lot more… but for the time being, at least when used by groups like Swedish House Mafia, that’s what it does. Assuming the smartphone holders have the SHM app.
The audio channels carry over the noise of a loud concert or event, but not so far that the organizer can’t control screens differently in different zones. So a wave a color is possible, even if pictures and words can’t be displayed as they can if you have a regiment of trained people sitting in seats holding color placards.
Sonic Notify’s solution has the advantage of using existing hardware — users’ phones, and a venue’s speakers — but then it does require that users dig their phones out of their pockets at the right times and hold them up. And some of them are going to get dropped.
Another solution is the Blink FX Wink system. On the user side, it’s a cheap little wristband with a few multi-color LEDs and a battery in it. The wristbands get control data over infrared, which is a very cheap remote communication scheme. Roadies do have to set up IR transmitters, though.
As with Sonic Notify, the system can be controlled by standard DMX lighting controls, and resolution of the mass display is limited to zone control, not individuals — although with this system, you can have some wristbands on different “channels” to create a flickering effect out there in the stands.
Blink FX bands cost about $5 each. They can be sold or given away, and when they’re branded, they become a nice little souvenir with a logo on it. They really don’t do much once they leave the arena, but the company is planning on releasing a home version of the IR transmitter for about $150, so you can throw your own raves.
Infrared or sonic, you can’t transmit a whole ton of data through a non-radio channel. The Sonic Notify people told me they max out at about 200 bytes per second, or “old modem speed,” they say. But you can do cool things like send telemetry or control signals, or use audio tones for local handshake before sending more data over a faster network (that’s what Evernote Hello’s Connect feature does).
There are a few companies working on using audio in these ways; using light as a signal is more limiting. If you’re working on a system that depends on proximity of other devices, it might be worth checking these audio guys out.
- Rafe
See also
Xylobands
Chirp.io
Sonic Share
Shopkick Rewards Shoppers With a Silent Signal
Former Google Wave developers use soundwaves to share data between devices
Audio version of this column
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