[Akiba] over at Freaklabs has been working with electroluminescent (EL) wire. An entire dance company worth! We know [Akiba] from his post tsunami radiation monitoring work with the Tokyo Hackerspace. Today he’s one of the engineers for Wrecking Crew Orchestra, the dance company that put on the viral “Tron Dance” last year. Wrecking Crew Orchestra just recently put on a new production called Cosmic Beat. Cosmic Beat takes Wrecking Crew’s performances to a whole new level by adding stage projection mapping and powerful lasers, along with Iron Man repulsor style hand mounted LEDs.
As one might expect, the EL wire costumes are controlled by a computer, which keeps all the performers lighting effects in perfect time. That’s where [Akiba] came in. The modern theater is awash in a sea of RF noise. Kilowatts of lighting are controlled by triacs which throw out tremendous amounts of noise. Strobes and camera flashes, along with an entire audience carrying cell phones and WiFi devices only add to this. RF noise or not, the show must go on, and The EL costumes and LEDs have to work. To that end, [Akiba] He also created new transmitters for the group. He also changed the lighting booth mounted transmitter antenna from an omnidirectional whip to a directional Yagi.
The EL wire itself turned out to be a bit of a problem. The wire wasn’t quite bright enough. Doubling up on the wire would be difficult, as the dancers are already wearing 25 meters of wire in addition to the control electronics. Sometimes best engineering practices have to give way to art, so [Akiba] had to overdrive the strings. This means that wires burn out often. The dance troupe has gotten very good at changing out strands of wire during and between shows. If you want a closer look, there are plenty of pictures available on [Akiba’s] flickr stream.
Oh yeah that never gets old.
Now if you’ll excuse me…I’m going to go have an epileptic seizure.
Really? Or are you just saying that cause you don’t like light shows?
I find the dancing itself quite boring actually..
Fun!
I love this EL wire, but I just can’t think of that much stuff to do with it, besides “arty’ kinda stuff.
I wonder if Akiba could have gone with an IR blaster to sync everybody’s costume instead of RF. Put a couple IR blasters over the stage, and a couple sensors on each costume to receive sync pulses from all four sides, and forget the RF noise.
Modern theatrical dimming is almost all IGBT and SCR rather than triacs. Reduced RF noise due to chokes and such as well. Real problems are indeed audience cell phones and wifi access points, but add microwaves [a la food] and the welder out on the dock running during the show, the security team using their radios, local TV, FM, CB, and Ham transmissions….
PWM/PFM overdrive is a way to get the brightness without the burnout [as often].
As to IR comm with anything on a modern stage, forget it. The IR wash from modern luminaires swamps it immediately. Even if it is pulsed/coded/ carrier wave loaded.
Are you sure about the SCRs vs TRIAC? Because a TRIAC is basically an SCR like device suitable for AC. And if I don’t have AC (LED, fancy gas discharge lamps), I will use MOSFETs or IGBTs. But more and more lamp control (LED driver) is done by switch mode PSUs. And these can give even more EMI than TRIAC (or SCR) based electronics if not constructed properly.
You will not use PWM on an EL device, as they do not like DC. You can go up in the drive frequency, this was done for the TRON movies – up to 8kHz (instead of 1 or 2). I have been told, the actors had to wear hearing protection in the motorbike helmets, because otherwise the noise of the transformers would have driven them mad.
When I did this, I did not have the time to develop high frequency drivers, but after some testing I did overdrive commercial transformers with about 20V instead of 12V. It worked for the show.
And because of the RF noise: I expected very high traffic in the 2,4GHz band at an event like the eurovision song contest. So we decided to preprogram the sequence in each controller and let the transmitter which was tied to the DMX system just give the start signal. Then the sequences run autonomously
I gotta wonder why they aren’t using LEDs and “lightpipe” instead of EL? Build two boxes (upper and lower) with LEDs and fittings for the lightpipe, then simply do the neon thing and cover the parts of the lightpipe you don’t want to show. I would guess that modern superbright RGB leds (10mm for the tight angle prob) could easily outshine EL for those lengths. Might need some basic lensing to get in the the TIR range, but that can all be small and plastic.
Those poor performers. I bet they hear that damned “EEEEEEEEEEEEEEEEEEE” sound in their sleep.
The modern EL wire isn’t as bad, especially if you use PFM like OP says.
Also the best thin wire tends to use the 6 strand so a single point failure just causes brightness loss not an outright failure.
I’ve also had success driving this from both ends at once so if a fault occurs you just detect it in software and cut off the damaged section to regain at least some functionality.
Also, if the noise is a problem why not use noise cancelling via a little speaker? Run all the wires in phase and have the controller compensate with an antiphase output in the helmet etc.
All I can think of is “How many shows until the wires snap?”
So many flexing joints :(
Great stuff – way to go Akiba!