I finished the first segment of the tweetshirt 2.0 today.
It's a 8x8 matrix of superflux RGB leds stitched to a piece of textile.
Darn! It took me me 4 evenings to sew the 64 leds on the cloth with conductive thread I got from sparkfun.com.
This is the backside - 256 connection points.
The worst part is that the thread frays like mad so you really have to be very careful with the amount of stitches you can make.
This is the front side
It's hyperflexible and very wearable, allthough I'll have to add some insulating layers to keep the thread from short-circuiting (which is harmless with such low voltages and leds)
Next step is to figure out a decent way to hook it up to the Arduino. I could use a Lilypad of course, which is designed for these things, but I want to keep it more modular and simple.
The goal is to have more then one of these patches connected together to form a bigger display, so I have to figure out some protocol to control multiple matrixes with 1 controller.
Probably I'll attach a shiftregister to each matrix and connect those to the arduino.
It would be really cool if I could manage to make each matrix a bit standalone so I could just chain the next patch with 4 metal push-buttons ... well, that may be one bridge too far - we'll see.