Flip-dot displays are grand, especially this one which boasts 74,088 pixels! I once heard the hardware compared to e-ink. That’s actually a pretty good description since both use a pixel that is white on one side and black on the other, depend on a coil to change state, and only use electricity when flipping those bits.
What’s remarkable about this is the size of the installation. It occupied a huge curving wall on the ooVoo booth at 2015 CES. We wanted to hear more about the hardware so we reached out to them they didn’t disappoint. The ooVoo crew made time for a conference call which included [Pat Murray] who coordinated the build effort. That’s right, they built this thing — we had assumed it was a rental. [Matt Farrell] recounts that during conception, the team had asked themselves how an HD video chat for mobile company can show off display technology when juxtaposed with cutting edge 4k and 8k displays? We think the flip-dot was a perfect tack — I know I spent more time looking at this than at televisions.
Join us after the break for the skinny on how it was built, including pictures of the back side of the installation and video clips that you have to hear to believe.
Shockingly Short Development Time
Get this, conception to finished construction for the wall was just under two months. The first pitch for funding happened the last week of October and the rig was finished about a week before Christmas.
In the video below you can just make out the panels which make up the display. Each of them hosts a 28 by 14 grid of flip-dots. The panels are arranged in 21 columns of 9. This provides a black and white display resolution of 588×126. Cognitively, that’s horrible resolution. But the sheer size and novelty of the technology makes the 74,088 mechanical pixels look and sound stunning as they click their way from one state to the next.
Each module has a built-in controller which are commanded via serial. To gang 189 of them into a single display, [Pat] sourced some serial to Ethernet hardware from Grid Connect. These adapters report back to a single computer via 64 Ethernet cables. That box plays back a video file, adapting it on the fly using Adobe Air to send packets to the IP addresses of the Ethernet controllers.
All of this is supplied by a trio of 56A, 24V power supplies. At a refresh rate of 30fps, when flipping all the dots at once this is a max current draw of 189 panels * 0.680 Amps = 128.52A @ 24VDC (Same power as 28 Amps @ 110VAC = 3085W).
Making it Interactive
The display wasn’t just rolling video. Interspersed with ooVoo’s advertising these cartoon faces would emerge. Space evenly along the length of the display are PrimeSense depth cameras. [Pat] told us that these were chosen over the Kinect sensors because they are more suited for up-close facial recognition. In conjunction with Affectiva and Faceshift, your facial disposition is measured and translated to the cartoon character. Each sensor has its own Mac mini which parses the data and sends commands over the network to the box controlling the display.
Our European readers may get a chance to see this one in person. ooVoo will be taking the display to the Mobile World Congress in Barcelona, March second through the fifth.