Jumping ghouls, giant roof spiders that rear up, and simple repetitive motion are what I would consider simple or "coarse animation".
This page is dedicated to "precision animation", where the moving part has to go exactly there and here in order to make the effect work. To a great degree, repetitive sequences of complex commands can be programmed through the use of cams. That's essentially how music boxes and player pianos work. But here we are interested in digital control.
This is most frequently accomplished through the use of either stepper motors or RC hobby servos, with or without a computer in the loop.
A solenoid is a coil of wire that becomes a magnet when electricity is applied to it. The most common form of this has a hole in the middle with a piece of iron in it. When the solenoid is energized, the iron rod can push or pull, depending on the design.
Haunters are most likely to encounter solenoids in valves used to control compressed air for an animated scare. In this case, the magnetism of the energized coil actuates a valve that allows the compressed air to flow.
But even without the valve, solenoids can provide a helpful push or pull. In our spider spitter, we use a pull-solenoid to activate the nozzle on a can of shaving cream.
We have a whole page dedicated to RC servos.
Thank you for visiting. Your comments are welcome.
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