History: (3) Inventors and Manufacturers: (2) Model Development and Design Types: (2. 3) Spiral Escalators: The Mitsubishi Electric Corporation was most successful in its development of "spiral" (more "curve" than true spiral) escalators, and has sold them exclusively since the mid-1980s. The world's first "practical" spiral escalatora Mitsubishi modelwas installed in Osaka, Japan, in 1985. In use, a major planning advantage presented by spiral escalators is that they take up much less horizontal floor space than traditional units, which frequently house large machine rooms underneath the truss. Helixator, an experimental spiral escalator design which currently exists as a prototype scale model, could further reduce the floor space. The design has several innovations that offer the possibility of a continuous helix. Driven by a linear motor instead of a chain system, the Helixator spreads the force evenly along the escalator path, avoiding excessive force on the top chain links and removing geometry, length and height limits