The two Korean manufacturers Hyundai and Kia are hugely investing in the studies aimed at the optimization of the usable spaces in the architectures of the vehicles of the future and they have recently presented the Universal Wheel Drive System – Uni Wheel – the “powered wheel”, a traction system that enables greater freedom in the design of electric cars. The primary advantage is the enlargement of the inner space, opening new possibilities and minimizing transmission shafts’ length. A solution particularly suiting special vehicles, like for instance shuttles and those for the transport of people or materials with autonomous drive, like the so-called Purpose Built Vehicles (PBV).
Uni Wheel, for which 8 Hyundai and Kia patents have already been filed in South Korea, USA and Europe, exploits a special planetary gear configuration consisting of a central gear, four pinions on each side connected in series to it and an external ring gear: the power generated by the motor is transmitted to the central gear, which in its turn engages the pinions to rotate the ring, connected to the wheel. Uni Wheel can transmit the power without losing too much in efficiency, irrespective of the wheel motion, and it finds perfect application coupled with electronic pneumatic suspensions able to adjust the vehicle’s height according to the drive situation.