Theo Jansen whom I visited years ago in his atelier in the Netherlands is an engineer, sculptor … an artist. While offering a nice cup of tea he explained his main project of the last 15 years. Starting with a computer simulation he calculated the right lengths of the elements of a mechanical linkage that is able to convert a rotation in a kind of walking movement. Lifting a foot, putting it in front, striking it … After he found the right proportions for the linkage of one leg he combined several of those legs to build the walking mechanism. The movement of all the legs is synchronized via a connection to the main rotation axis via an individual phase shift. Big wing like sails capture the wind’s energy to drive the whole walking mechanism.