This is a polargraph (drawbot) gondola for drawing "light paintings" with an LED. It uses the polargraph's "pen lift" servo to turn the LED of and on, so no changes to your polargraph's firmware is necessary.

Find more Info about polargraphs here: http://www.polargraph.co.uk/

Light paintings are slow shutter speed photos, usually in a dark environment with moving light sources (or a moving camera). With this gondola and a polargraph, you can render photos or SVGs (vector art) with a small dot of light. Slowly.

www.thingiverse.com/thing:38216 Parametric Battery Clip by holgero was the basis for my battery holder. Thanks, holgero! I rebuilt the mesh entirely and changed the design somewhat, mostly to make wiring easier and battery removal less a struggle.

www.thingiverse.com/thing:29734 9G Servo in OpenSCAD by TheCase was used for size reference, and is included in the .blend file. Thanks, TheCase!