Skytran (stylized as skyTran) is a personal rapid transit system concept. It was first proposed by inventor Douglas Malewicki in 1990, and is under development by Unimodal Inc. A prototype of the skyTran vehicle and a section of track have been constructed. The early magnetic levitation system, Inductrack, which SkyTran has replaced with a similar proprietary design, has been tested by General Atomics with a full-scale model. In 2010, Unimodal signed an agreement with NASA to test and develop skyTran. skyTran has proposed additional projects in France, Germany, India, Indonesia, Malaysia, the United Kingdom, and the United States. System details To minimize maintenance and make switching on and off the tracks efficient at high speeds, early versions of the system proposed using the Inductrack passive magnetic levitation system instead of wheels. Passive maglev requires no external power to levitate vehicles. Rather, the magnetic repulsion is produced by the movement of the vehicle over shorted wire coils in the track. The cars would be driven by a linear motor in the track or vehicle. Therefore, the system would have no electromechanical moving parts, making it entirely "solid state". On this first version, the passive maglev coils are enclosed and supported by a light shell called a guideway that also captures the vehicles mechanically to prevent derailment. Malewicki proposes a 3D grid design that avoids accident-prone intersections by grade separation, with guideways and their exit and entry ramps crossing above or below each other. Tracks will be supported above the ground by standard metal utility poles. They could also be attached to the sides of buildings. After identifying problems with Inductrack and the cost associated with it, skyTran described an improved design during a Horizon BBC interview with skyTran at NASA Ames in Mountain View, CA. New details about the levitation and motor were described in a keynote speech in June 2016, showing levitation stator being plain aluminium plates and motor stator an aluminium tube. The guideway is also significantly enlarged and wider than the vehicle, so the switching can be vertical, going through the guideway. Guideway shape is shown at 16:26 in above referenced video. This new concept can be seen in a short simulation film. Instead of the purely passive inductrack system, the new mechanism modifies lift by mechanically angling the magnetic pads and need a servo controlled actuation. The lift control also do the switching by moving vertically through