Theo Janssen builds his "creatures" out of PVC pipe, zip ties, plastic soda bottles, bicycle pumps, tubing, and thin plastic sheeting. And powered by the wind, they walk – even storing up wind energy as compressed air inside the bottles. He has invented a new type of articulated leg that is nearly as friction-free as a wheel. Though the overall design of the machine shown above is my own, I have scrupulously recreated Janssen's unique leg design.

This prairie clan has built their walker from similarly lightweight wood, reeds, stretched hides, cloth, fired clay, and a few parts of metal. The zeppelin-like top half gathers wind energy via its flapping, fin-like vanes, and pivots freely to track the wind. It transmits its power down to the legs via a vertical shaft in the exact center of the pivot.