Optical fibers are individually poked through the fur. Exact distance is important -- long and you see the classic and distinctive point of light, shorter and the light is dimmer and more diffuse.

To prevent the fibers from being pulled through, I used a few wraps of tape to create a stop. Each stop was marked with a color corresponding to one of the five "channels" the fibers are grouped into.

Fibers are held in place with iron-on fusible interface. I wasn't able to find much previous documentation on this process for putting fiber optics into fur, and this method seemed to work pretty well. Too much ironing can cause the fiber optics to warp.

Lighting test.

Fibers are clumped into channels and attached with heatshrink to 5mm WS2812 LEDs.

The LEDs are driven by an ItsyBitsy M0. There's also an LIS3DH 3-axis accelerometer.  Electronics live in a little enclosure mounted to a waistbelt.  Power is by a 1200mAh LiPo


The tail has four modes:

- Reactive Stars -- white points of light. Will flicker occasionally at rest. During intense motion (e.g. dancing), the stars twinkle furiously with subtle hints of color. 

- Fire

- Aurora

- Rainbow. I think RGB color spin rainbows are usually boring and overused, but I had a fourth input button available.