This started out as a project to learn modeling in FreeCAD. I've attached the FreeCAD project file as well as the .stl models.
I'm not sure what I'll do with it, but it seems like it would work nicely in some kind of Halloween costume.
The main bracket works like a clip-on spray-paint trigger -- In fact, the bracket should fit other kinds of rattle cans as well.
The servo bracket was modeled to fit a hobby servo I had lying around. I've found that servos have a variety of different mounting screw patterns so you might have to modify this for whatever servo you're using.
A bent bit of paperclip works to connect the servo horn to the end of the trigger.
Here's a short clip of it firing: http://www.youtube.com/watch?v=fPpnoXX5sNc
I just learned that this design is used in the Icarus One spray paint drone by the artist/vandal KATSU.
bracket.stl | 296.3KB | |
servoplate.stl | 110.2KB | |
StringFling.fcstd | 352.2KB | |
trigger.stl | 89.3KB |