project: sound scales swatch

Unfortunately, I can't make it to the eTextile Summer Camp this year, but I'm still participating in the Swatch Exchange!

I'm building 20 examples of how I integrated piezo elements into paillette fabric for the Sound Scales dress. Instead of mounting it on fabric, I decided to make the circuit from paper and copper adhesive. To replace the Arduino-generated PWM sound wave, I'm using a 555 IC to drive the sound. I've also integrated a pressure sensor in the circuit, so that the frequency of the sound can be manipulated.

In case you're interested, here's a link to last year's Swatchbook Exchange. And my contribution, which was based on research from the Manifold Project.

progress: finished!

The swatches are finished and ready to be shipped to Hannah in Berlin. Photos below, and I'll put more details on my swatch page on the Summer Camp website.

...and a little video of the functionality...

watch on vimeo

progress: paper circuits

Twenty circuits - almost complete!

I also cut the Velostat pressure-sensitive film on the vinyl cutter (seen here in black).

design: copper foil circuit

I'm using an astable 555 timer circuit to generate a pulse to create the piezo sound. Because I'll be using adhesive copper foil, the circuit will be single-sided and single-layered. I'm using SMD components to minimize bulk.

Here's my circuit diagram and layout in Illustrator:

I'm using my vinyl cutter to cut the circuit, so can't make the traces too thin. A 2mm minimum seems to be a good rule of thumb. I've also tried to use curves where possible, so that peeling the copper will be easier, plus it's a nice stylistic touch as circuit boards are usually hard angles. In the future, I'll probably try to design the circuit to reduce waste as part of the layout.