Ask HN: How were the super bowl led torches synced? | Hacker News Reader

Ask HN: How were the super bowl led torches synced?

My guess is via each volunteer's phone. Anyone with a better guess?

I'd be tempted to think they decided to solve the logistics challenge instead of the technical one. So instead of trying to build a generic piece of hardware that detects its own position and lights up accordingly, each torch was unique (or configured via software to be unique, even if at "runtime") and configured specifically for its exact position on the field.

If each torch is designed for it's own show, then the only thing that has to be synced is the exact time to start. And in comparison, that problem is trivial to solve with known constraints (as opposed to triangulating hundreds of devices with < 1ft precision in addition to actually synchronizing the devices)

but didn't the torches move out when they had the sort of starfish shaped formation and they were all yellow? seems hard to believe they would've been able to coordinate the extras moving far away and then moving right back in position.

What about something low tech like: the field has a grid with infrared emitters pointing up spaced let's say 6 feet apart, when changing positions extras have to keep the torch vertically for a second for it to receive its id from the local emitter, then you simply broadcast every instruction to everybody and each light knows to look only for instructions for its id

As long as you are ok with setting up the emitters on the ground and the assumption that you can "re-sync" the position at every position change, seems like it'd be fairly straightforward

It isn't that hard to coordinate professional dancers to do what they did.

Yeah, don't overthink the starfish pattern. There were radial and linear sweeps that were probably RF time-of-flight controlled, but not that part.

so are you saying all those people are not some random spectators of the show but super bowl crew? Or random spectators who guarantee that they wont move from their predefined position?

The people holding them had some synched up dance moves, so they definitely had practice

The audience was doing choreographed moves during certain songs, so it was not random at all.

I don't think they were professional dancers, but I also don't think they were random people. Screened and rehearsed locals seems the most likely.

Not super hard to believe that the NFL was able to recruit Houston natives to do this for free in exchange for a close up concert with Lady Gaga and being on national TV.

I figured the dancers were just doing it manually.

edit: after a few rewatches, there's definitely a few places where (non-Chinese) human timing seems unlikely but I'm still hoping it was manual.

RAIN Rfid can do this for moving objects: https://www.youtube.com/watch?v=p1LykdRWTfk

View Technologies can track a moving RAIN Rfid tag to the size of a softball in a xyz plane in realtime.

I believe this is the correct answer. The people in the "crowd" holding the torches were also dancing in synchronization with parts of the music, so they obviously practiced beforehand and I'm tempted to assume they each had an assigned spot to stand in at certain times. Given that they were in predetermined positions, the LED synchronization would be trivial.

The dance was rehearsed ahead of time and the torches get lit via infrared sensors. (I magically discovered the infrared when I was pressing my TV remote and it just lit up).

This is done by shining bright Infra Red lights high in the stadium down onto the crowd. We cannot see Infra Red light ourselves, but the lights/torches the crowd holds can detect the infra red light and respond when they see it by switching on and showing visible light we can see. Thus all the lights the crowd have can be commanded to light up at the same time, or turn off at the same time. In advanced situations the infra red lights can trigger mass synced colour changes in the lights the crowd holds, exactly the same way an infra red remote control commands a TV to do different things. Cheap and effective tech.

There's got to be more to it than that. Even with a really tight beam you'd run into all sorts of "Am I in the spotlight or not" problems, especially with the torch flailing around while someone dances (illuminance detected would be all over the place).

Looking at this video

https://www.youtube.com/watch?v=fYDSguhC4FQ

It seems advanced patterns only turn up when people are in a roughly grid arrangement, and no one moves out of their spot except at predetermined times (obviously everyone is in on the choreography here). There are also dark periods after people finish moving around and "get in place". It looks like they are doing some degree of calibration. The torches my well have IR lights on them too that can be individually addressed to quickly calibrate every torches position, sorta like marco polo. Break it into quadrants and you could do it even quicker.

It could be simply overhead IR lights, but gah, they are doing something really special to get those well defined sharp edges.

Besides all that, everyone could just have assigned spots that they memorized. It's obvious they practiced, and arranging a bunch of people on a field quickly and fluidly is nothing new.

PixMob (https://pixmob.com/en/) has been used in past superbowls to create similar effects, which aparently uses IR.

Yes, PixMob also produced synched LED bracelets for Taylor Swift's most recent tour. Here's a video of that in action [1] and a video showing various events they've been at [2].

[1] https://www.youtube.com/watch?v=W2hNcJeeDsM

[2] https://www.youtube.com/watch?v=hYnaMaKj27M

Those weren't localized to seat location, like that of the super bowl show.

Didn't see the Super Bowl, and can't comment on the technology used, but I've been looking into Xylobands, http://xylobands.com/, that have been used by Coldplay in some of their concerts.

Technically, that's a LED (monochrone, later they used multicolor LEDS) with a radio receiver. Radio transmitters were installed throughout the stadium, controlling specific LEDs to go one or off.

See https://www.youtube.com/watch?v=JficYgaK8j8 for some background video and the use in the song Charlie Brown in the Mylo Xyloto tour.

Maybe it was this guy? https://www.reddit.com/r/IAmA/comments/5pouv4/18_months_ago_...

This was my first thought too! Would be really cool if he was behind this :)

If I was preparing to show off my tech at the Superbowl, in front of 100 million people, I wouldn't be doing an AMA a few weeks before.

I'm curious how the one commercial knew the score was 21-3 ... Did they record a bunch of versions which covered most possible scores? Did Fox dub in the score right after halftime?

It was a live commercial: http://money.cnn.com/2017/01/25/news/companies/snickers-live...

FWIW, link above has auto-playing video with sound.

Just enjoying the idea that they recorded enough possible score combinations to get 21-3 falcons leading correct.

That definitely wouldn't be at the top of the permutation list. :)

The company that makes the torches is Glow Motion. It's RF tech, but they're not super-specific about how it works. They do say it only requires one antenna, so it's doubtful they were triangulating the location of each device.

http://www.glowmotiontechnologies.com/how-it-works

It's the same company that did the illuminated kinetic beach balls in Drake's recent tour.

Source: http://livedesignonline.com/super-bowl-li-2017-halftime-show...

https://github.com/jamrader/XTAudioBeacons

maybe

That sounds like something out of a Bond. (Pun intended)

I'd be really interested in how far this can work effectively. Could we build solar phone booths in a forest that will flash a light (to make them easy to find) if they hear an warning siren from the rangers? Maybe also if someone is yelling in pain so they know where to call for help.

Could anyone here explain what happened? Didn't see it and tried to find it on Google/Youtube, but only this thread shows up. What effect are we talking about?

Was wondering the same thing. Either each volunteer was in a predetermined location with specific uuid'd torches or there some newfangled rfid/bluetooth location tracking to within one foot or so that I want to know about. My money's on the later, can't trust 100s of people to be where you told them to be during a live performance who aren't professionals.

Why do you say that they weren't professional dancers?

No Spandex

Imagine you had all the torches lifted up in the air throughout the entire duration of the show. As long as the 'human' stays in place, and as long as you know the uuid of each device; you can make any shape you desire.

Wifi? I've worked on something similar:

http://magicshifter.net/

I don't know exactly how the torches look, but I can imagine they have an indoor GPS setup in the stadium. Couple that with a position-dependent program that each torch has. The actual program can be started, paused or stopped using an RF signal of some sort - so the torch actually knows its position and just sets itself to what should be running on the virtual, stadium sized display.

Maybe triangulation with beacons?

This is what I would assume. They weren't perfectly synced (although very close), so it appeared to be some sort of localized position detection.

They weren't perfectly synced, so I would assume the field audience just all pressed the "go" button at the same time (indicated by handlers with headsets, presumably)

Much simpler than localization.

Maybe Bluetooth paired with phones

Infrared.

Is this honestly not trivial in 2017??? Given this didn't have to be perfect, there are 3-5+ ways to do this.

That did not answer the question, so I am going to assume the answer is not trivial.

Don't be shy, what are the 3-5+ ways? Some of us aren't even familiar with the superbowl LED torches never mind the tech behind them.

Try to avoid faking surprise to make yourself sound smarter too, it doesn't work.

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