I first encountered (what is known on the internet as) a "Grave Jumper" while riding The Haunted Mansion at Disneyland in 1995. What is a grave jumper? It's basically a head or skull mounted on an air cylinder. When air goes into the cylinder, the rod inside the cylinder is forced upwards very quickly. Done right, it is a startling effect.
Some Grave Jumpers are very elaborate, but I'm making this one simple. I think my only mistake so far is using an air pump as a cylinder. It only went slow, and was leaking air. This time I will get a proper cylinder, one that's made for exactly this application.
This project was planned as early as 2004, and was started in August of 2010 when I finally got an air compressor. Preliminary planning started in July of 2010 with the construction of a frame made from a 21 inch(53 1/2cm) "2x"4 attached to a "12 x "12 (30cm x 30cm) plywood base with two screws.