Building Pulse and Bloom, an interactive biofeedback installation at Burning Man | Hacker News Reader

Building Pulse and Bloom, an interactive biofeedback installation at Burning Man

ofbrooklyn.com

155 pointsconesus24 comments

Hey HN, this was my first art installation and boy was it a whopper. Used by tens of thousands of people in 8 days, it had 40 hand-made pulse sensors, 200 high current LEDs, and 40 5 meter LED strips. All running off an ATmega328p chip.

Would love to answer any questions on building art installations.

Thank you so much for putting this post together. I was there and enjoyed it plenty. Its been a focus of a few discussions among friends back home in Bermuda.

By the way I've shared with the unofficial Burning Man fb group https://www.facebook.com/groups/burntheman/permalink/1015458...

Neat, I had never heard of that group and then I noticed 21 of my FB friends are on it. Thanks for sharing!

...why would you make a Facebook group about this?

... to share snarky comments and bitch about things.

Why does anyone start a facebook group? what about BM makes it non-facebook-group friendly? There are a lot of loosely connect people that meet through BM or regionals, facebook is actually a pretty well-suited platform for discussion.

What did you do for solder paste? Seems like most places only sell it in large expensive quantities that have an expiration date.

Originally I bought leaded solder paste from McMaster Carr, but then I discovered a lead-free solder paste from Sparkfun: https://www.sparkfun.com/products/12878.

It's not as good as the leaded solder paste, but hey, no lead. Also, you should refridgerate it at all times. You don't have to, but it doesn't spread nearly as smoothly.

And I just used the credit card OSHStencils.com gives you with their film stencil. Works on QFN and other fine-pitch solder pads. Just gotta clean the excess solder off the film every 2-3 applications. Otherwise it blots and runs over the solder mask.

Cool, thanks. I have been using a standard chisel tip solder iron to do my .5 mm pitch components. It is doable after practice but it requires a flux pen and copper braid to make it work. Excited to see if the stencil hot plate method is easier.

You can buy reasonably small amounts of leaded solder of DigiKey. I would recommend it over SparkFun. That said, every solder paste has an expiration date and will go bad if not stored appropriately.

This project was a pleasure to interact with -- definitely one of my highlights this year. Thanks! And thanks for the great write-up / open-sourcing.

I think my favorite part was how they looked from far away -- the pulsing up the stem to the lotus was a super pleasing animation.

Thanks for bringing this to the playa, Samuel. Hope to see it again next year!

Some of the pictures made this look completely surreal - like some kind of mystical garden inside a Mad Max movie.

Very cool stuff. Would love to see more of your work.

Thanks for building it! It worked great and I sat there with someone for a good 15-20 minutes playing with it :)

That's a really lovely idea. Congratulations on pulling off your vision.

It's awesome to see how much work went into it. When you're wondering around the playa it's easy to get lost in all the wonderful things going on and not take the time to step back and think about how much work goes into each individual installation.

Every time I see a clip from Burning Man I long to go back there again (I'm in the UK, so it's not so easy). It's surely one of the greatest sensory displays of hackers crafting wonderful work on the planet.

I'm interested in biofeedback. And it saddens me that ecg sensors aren't out there for people who aren't electrical engineers (or with equivalent non-formal knowledge in this topic). Neurosky reportedly has one in the works (but probably also 50-100$).

The problem with most heartbeat sensors is that they only give you a frequency. They don't tell you when the heartbeats arrive, or, god forbit, anything interesting about the actual signal.

Here's an actual video: https://www.youtube.com/watch?v=fucQFf7Txws (surprised to see there wasn't a video on OP's page)

There's a video at the top, it's the first graphic. It is also 42 MB, so it may take a while to load.

This is awesome. I just completed a simple first foray into attaching circuits and LEDs to one of my welding projects, and seeing a walkthrough of the steps that I also had to figure out (culminating in an impressive large-scale installation!) is fascinating. Thank you so much!

edit Btw, also amazing that you were willing to lug the battery back to camp and recharge it via solar power. So many installations out there are marred by the grating sound of a generator in the background.

Any issues with the alkaline dust causing issues with the electronics?

Oddly no. There's a photo in the post where I show a well dusted board, but no shorts were caused by the dust. There was definitely weatherproofing we could have performed on the boards to handle that issue, but I was waiting until it actually became a problem.

It did rain one day, but only during the day when the installation was off. And thank goodness because if the installation was on, not only would we have a pickle of an issue with all of our exposed wiring, but we would have to get to the middle of the playa in the middle of a rainstorm. It's nearly impossible to move when it rains since the dust cakes onto your shoes and eats everything alive.

I've been there when a dust storm and rain storm were happening at the same time. It gets pretty alien and unreal.

Ambitious installation. well done!

Yup, was going to mention conformal coating (keyword is important for the electronics side of things). You can get it in a spray can and it goes on like a lacquer, pretty simple (might need to tape certain parts if they need to be exposed). A good conformal coating can withstand the acrid nature of coal plants, I bet it can also handle the playa (though it seems like things fared pretty well as is).

Great project and thanks for the writeup! Hope to see you at future hw meetups in SF! :-)

I've never had problems with playa dust (other than the usual corrosion - just wash everything when you get back)

As far as soldering QFN parts is concerned - hot plates suck because you can't control the reflow envelope - if you're doing it by hand I think better to use a hot air rework station, drop some paste on the pads, pop the die on top, fire up the air until you see it float on the liquid solder and let it cool - if it doesn't work rework is easy (heat it up again then lift it with tweezers.

Alternately real reflow ovens are cheap from China

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