Animatrons

During some parts of our haunt, we needed a way to animate a prop with what seemed to the viewer as non-repetitive movement but yet operate independently. Hence the stepper motors and computer. Sure there's other ways, like servos, but we had the parts and the time. Besides, stepper motors are easy to manipulate, cost effective and offer a range of uses.
Our Toxic Man was one of the first attempts. His head was simply attached to the stepper motor gear. He worked OK, but weight and balance were a problem.

So, back to the drawing board, we mounted a stepper motor inside a metal wall outlet box. Mounted a larger gear on top of the stepper motor gear. Beside it, we drilled a hole in the outlet box and halfway through the wood base to accept a metal rod, (dowels work fine too). The rod is for the styro wigform head (see Headmolding). A small hole is drilled in the top end of the rod to accept a small brad.

The head is then mounted on the rod with brad crosspin and the hole filled with expanding foam. The device is then mounted in an armature and is ready to operate.

There are so other varied uses, stepper motors can be used to control cameras, to animate spiders dropping from the ceiling, rats moving around a table and to animate images projected off rotating mirrors. You're only limited by your imagination.

PS

For those attention to detail people, Toxic man was mounted in a 55 gallon drum. A cardboard top was placed around the top of the man & can, covered with self-expanding foam to look like bubbles, painted a sickly concoction of yellow green and purple and a biohazard sign taped to the drum. This effect works well with a "trashcan trauma" effect.