Sketch 1: Circuit Construction

Alright, so I had no experience with EL Wire at this point. We purchased an EL Sequencer to be able to animate the lights.

I used this tutorial from Bildr.org to help me get started with the EL Sequencer.

Once I got lights blinking and fading, I integrated the stretch sensor. I actually had worked with creating a breath sensor for another project in Physical Computing, and was able to easily incorporate it with the EL circuit.

To measure the breath, I used an stretch sensor band wrapped around the abdomen. When the user inhales, the abdomen would rise, causing the band would stretch, increasing the resistance. Exhaling would cause the abdomen (and the band) to contract, decreasing the resistance. I inserted the output voltage of a voltage divider circuit incorporating the sensor to one of the analog inputs.

I programmed it so that exhalations would result in the light dimming, and inhalations would result in the light brightening. I took several readings from Noemi, in order to determine the maximum and minimum incoming voltages from her breath. Using these values, I mapped incoming voltages to 0 to 255, so when Noemi reached her minimum/maximum breath points, the light would be fully on or off respectively with fading values in between.

Here is the final diagram:

With the final diagram in place, I got rid of the breadboard and alligator clips, and began stitching the main soft circuit with conductive thread on felt. (Note: I forgot to put the battery back in when I took these pictures).

We also stitched the stretch sensor on an elastic band that Noemi could wear under her chest.

Here is the front of her leotard:

And a close up of the band on her back:

In order to connect the stretch sensor to the main circuit (which we planned to place under her skirt), we added two fabric strips with two snaps (power and ground) on both ends, connected respectively by conductive thread.