Mel Ristau is the father of Aaron Ristau, who’s shown his work at Maker Faire and has a store in the Makers Market. Dad is an artist too, an amazing sculptor. He sent us a link to an article he posted on his blog detailing the basics of load, leverage, and effort as applied in kinetic sculpture:
A kinetic sculpture is an artwork designed to move. Having mechanical advantage, levers can make it easier to get things moving. Movement can be achieved by capturing environmental energy (effort) like wind or water or by employing effort generating devices like motors or muscle wires. The presence of effort can result in movement that rearranges parts of the sculpture.
In the drawings above, E = effort, F = fulcrum, L = load.