False Profit Labs is proud to bring The Hydrogen Economy and PyroCardium to Maker Faire. Especially now that our circuitboards work! The last few days have been a bit harrowing, since the first time we fired up all twenty of our the flame effects, we blew up our power supply. Kurt Thorn revisioned the electronics in 24 volts DC instead of the high-voltage AC line we were using and at 11:30pm last night PyroCardium came to life.

We’re jamming a lot of technology into this project of computer-controlled fire. The little sculpture is a prototype, with a 20-foot-tall spiral to follow for Burning Man in August. It has 16 flame effects, each a small propane venturi flame pipe with a solenoid valve. All the flames are fired individually by a USB-connected driver board controlled by a False Profit Labs software application that runs various flame algorithms. Each algorithm changes the response and patterns of the flame. And at Maker Faire on Saturday from 6-10pm you can place the PyroCardium stethoscope on your chest and see your heartbeat race up the sculpture in a spiral of flames.

PyroCardium’s first test-run

Flame Tree Workshop participants at Alchemy light up their creations:

photo by broxtronix

Chris wrote previously about building nichrome wire ignitors. Now he’s got it perfected, and built a cloud of 20. What better to do than put the new bubble machine underneath?

For PyroCardium to respond to people’s heartbeats, we need a way to electronically measure their heartbeat.   Since PyroCardium started life as a VU meter for music, the obvious way to do that was to hook up a stethoscope to a microphone.  Today I tried to do just that.

I had some cheap electret mikes leftover from an earlier project idea (a music responsive EL-wire cape that never made it off the drawing board), so I decided to do the obvious thing and jam one into the stethoscope tubing.  I then built a simple amplifier with a gain of about 100.

Hooking it up to the oscilloscope, I could see the trace move when I put the stethoscope on my chest, but I had no idea what it was responding to - if it was really my heartbeat, or if it was just noise.  It took me a while to come up with a way to figure out what was going on, but eventually I realized that I could hook it up to my stereo.  A few alligator clips later, I could hear my heartbeat booming out over my speakers.

I think our stethoscope amplifier is solved.

Those of you at our last few workdays will have heard me moaning about transients from our new solenoids causing the PyroCardium USB controller to trip off. The back story is that the 24V DC solenoids we had been using before turn out not to have seals compatible with propane. So I’d like to switch to some 110V AC solenoids I have which have propane compatible nitrile seals. I got 16 of these solenoids for free from my dad - they’d be about $800 new.

The problems began when I replaced the 24V solenoids with the 110V AC ones. As soon as I tried controlling them from the computer, the software crashed immediately. When you turn off a solenoid, the energy stored in the coil gives rise to a rapid increase in voltage across the inlets. This is called inductive kick. I have a varistor in place to dissipate this kick, but it doesn’t appear to be enough - my theory is that this transient voltage spike is getting coupled into the USB board and giving rise to errors. This theory is supported by the fact that adding a capacitor in parallel with the varistor, which should also help dissipate the transient, reduced the crash frequency (though it still crashes after about 5 or 10 minutes of cycling).

To fully isolate the USB board from the rest of the system, I’ve ordered some optoisolators. Optoisolators chips that electrically isolate one circuit from another by coupling them with light. They have an LED driven by the input coupled to a phototransitor that forms the output. I’ll have them on Saturday, and with them I’ll be able to fully isolate the USB board from the high power switching circuitry. Hopefully that will fix our problems.

We’ve begun work on the PyroCardium sculpture, making a 6-foot-tall version with 1 Watt red LEDs to appear at False Profit Alchemy on April 26 at Cell Space. On the virtual side, the sculpture truss and helix is all modeled up in 3D using Rhino. On the physical side, the TIG welder is out, as is the metal bender, and the smaller truss is coming together.

Probably the most challenging aspect of building a swirly sculpture (aside from the dancing fire) is bending thick pieces of aluminum on all 3 axes. Dyche has come up with a pretty ingenious method. Our first helix will be comprised of seven semi-circles, of successively smaller diameter. Each piece of aluminum stock is placed in the metal roller at angle, so it gets bent in a semi-circle in one dimension, and pulled upward out of the circle’s plane as well. When these pieces connect together, the decreasing diameter is what gives the sculpture its skewed shape.

False Profit Labs has received grants from Burning Man for both The Hydrogen Economy and PyroCardium. We’re honored and really excited. Even though we’ve come a long way on the projects, there is much work to be done. I think that along with these grants comes the responsibility to deliver, and to bring what we’ve promised in our proposals to life out on the playa.

Since we had to put the proposals online quickly for this week’s Jack Rabbit Speaks (JRS), I dumped images out of the proposal PDF files and made these online versions.

The Hydrogen Economy
PyroCardium

I didn’t have much luck with the PDF to HTML conversion tools, so if you know of a good one, please post it.

False Profit Labs is happy to announce that we will be making appearances around the Bay Area in the coming months. First, on April 12 you can come out to NASA Ames at Moffett Field and enjoy our fire art out on the tarmac in celebration of Yuri’s Night. Check out their website here: www.ynba.org.Then on May 3 & 4 we bring more explosions to Maker Faire at the San Mateo Fairgrounds. More on this at: www.makerfaire.com.We’ll publish more details as we get them, but for now here’s an appetizing 3d model that Brendan Colloran made in Matlab(!) for the PyroCardium scultpure. Now it’s just a matter of building it.

In our latest workshop day, we got both The Hydrogen Economy V3 bubble machine prototype, and the 4-flame PyroCardium prototype working and ready for Maker’s Faire tryout day tomorrow at the Exploratorium. Then it was time for a little antics. Here’s a video of voice-controlled PyroCardium, held by Chris, exploding the bubbles or at least trying to.

They’re in.  And here they are so you can see not only what we’re up to this year for Burning Man, but also so you can get involved.  There are at least a dozen sub-projects related to The Hydrogen Economy and PyroCardium.  Maybe you want to help with construction of a double-helix sculpture, or you’re good at machining small plastic and metal parts.  Maybe you have no skills at all but are full of enthusiasm.  Perfect.  Post a comment with your contact info and we’ll find a way to plug you into the mix.The 2008 False Profit Labs Burning Man Proposals:

The Hydrogen Economy

PyroCardium