South Korean automakers Hyundai Motor Company and Kia Corporation have together unveiled the Universal Wheel Drive System, called ‘Uni Wheel’ at the Uni Wheel Tech Day in Seoul. The new vehicle drive system is touted to be a paradigm-shifting innovation capable of revolutionizing the design of future mobility devices. Uni Wheel is a functionally integrated wheel drive system moves the main drive system components to the vacant space within the wheel hub. This dramatically improves available space inside an electric vehicle.
Dramatic increase in interior space of EVs
The new drive system enables a flat-floor configuration in an EV which is obtained by moving the vehicle’s reduction gear inside the wheel hub, locating a compact individual motor close to each wheel, and reducing the length of the drive shafts. This in turn increases the interior space inside an EV when compared with conventional drive systems. “We are pleased to showcase innovative ideas that could become game changers in the future mobility market. We will perfect the technology so that customers can experience mobility in a completely different and new way,” said Senior Fellow at the Institute of Advanced Technology Development of Hyundai Motor Group.
How is Uni Wheel designed?
The new drive system uses a special planetary gear configuration consisting of a sun gear in the center, four pinion gears on each side and a ring gear surrounding this arrangement. Power generated by the motor is transmitted to the sun gear, which in turn engages the pinion gears to rotate the ring gear. This is connected to the wheel to drive the vehicle. Uni Wheel’s pinion gears are connected to each other to form two linkages, and this multi-link mechanism enables its multi-axis movement to allow a wide range of suspension articulation.
Purpose-built vehicles
Thanks to the new vehicle drive system, the possibility of optimizing interior space in an EV for purpose-built vehicles increases. This enables moving away from conventional seating arrangements designed around the driver, creating new interior layouts and designs for the era of fully autonomous driving. The freed up space can also be utilized to improve battery capacity and driving range.