Hyundai Unveils Universal Wheel e-Drive System, Boosts Global EV Manufacturing Capability

Hyundai and Kia, both brands of Hyundai Motor Group, unveiled their new universal wheel drive system for electric vehicles in Korea in November amidst the group’s dramatic surge in expansion of EV manufacturing capability. Uni Wheel is a functionally integrated wheel drive system that dramatically improves available space inside an EV by moving the main drive system components to the vacant space within the wheel hub.

In doing so, the automakers have designed a completely new structure for the drive system that uses permanent-magnet in-wheel motors smaller than possible previously. The motors currently being used for the Uni Wheel are 120kW/220Nm.

In internal combustion engine vehicles, power is transmitted from the engine through the transmission and to the wheels via drive shafts and constant velocity joints. In EVs, however, the engine and transmission are replaced by a motor and reduction gear, but the final method of transmission to the wheels is the same. Uni Wheel opens new possibilities and enables a flat-floor configuration by moving the reduction gear inside the wheel hub, locating a compact individual motor close to each wheel, reducing the length of the drive shafts. The system frees up significantly more interior space compared with conventional drive systems, enabling future mobility products optimized for various applications.

“We are pleased to showcase innovative ideas that could become game changers in the future mobility market,” said Jongsool Park, senior fellow at the Institute of Advanced Technology Development of Hyundai Motor Group. Uni Wheel 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.

The pinion gears are connected to each other to form two linkages, and this multi-link mechanism enables Uni Wheel’s multi-axis movement to allow a wide range of suspension articulation.

A conventional drive system using a regular CV joint suffers from a decrease in efficiency and durability as the angle of drive shaft deflection increases when travelling over bumpy, undulating surfaces. Uni Wheel can transmit power with almost no change to efficiency regardless of wheel movement.

By moving the reduction gear to the wheel hub, a high reduction ratio delivers a significant torque output and allows for a more compact electric motor. With independent control of up to four efficient electric drive units, the system also allows for improved torque vectoring to boost dynamic ability and deliver high levels of steering and driving stability.

In addition to vehicles of various sizes, the system can also be applied to other types of mobility devices such as wheelchairs, bicycles and delivery robots. It can be scaled to work with wheel sizes as small as 4 inches and as large as 25 inches or more. Its ability to move the rotation axis of the wheel makes it possible to create forms of personal mobility that can climb stairs as smoothly as an escalator.

Immense building boom chases advanced EV design and production

Now one year into construction, Hyundai’s giant Metaplant in Georgia is on track to begin production in early 2025. Approximately 2,000 construction workers are working at the nearly 3,000-acre megasite site to keep the project on target, reports Hyundai America’s CEO Oscar Kwon. The $5.5 billion investment will establish manufacturing for an assortment of Hyundai, Genesis and Kia electric vehicles and a new battery manufacturing facility.
On November 12, Hyundai held a groundbreaking ceremony for a new EV plant at its complex in Ulsan, the heart of Korea’s automotive industry. Representing a $1.5 billion investment, it occupies a site of 548,000 square meters and will be able to produce 200,000 EVs per year. The first new plant for the group in 29 years, It will the hub for Hyundai’s mobility production in the era of electrification, says the company. Construction is scheduled to be completed in 2025, and vehicle mass production will commence in the first quarter of 2026. An electric SUV from luxury brand Genesis will be the first model to be produced at the new plant.
Also in November, Hyundai inaugurated its new Innovation Center Singapore dedicated to transform EV production, R&D and customer experience. The facility introduces a new ‘smart urban mobility hub’ concept which includes a highly automated flexible production system and provides creative ways for buyers to interact with their vehicles and the Hyundai brand. The seven-story, 86,900 m2 plant can manufacture up to 30,000 EVs per year. Operational since early 2023, it already produces the company’s IONIQ brand. It will serve as a testbed for developing future mobility solutions including purpose-built vehicles and robo-taxis. Approximately 50 percent of all tasks are carried out by 200 robots in a cell-based production system that leaves behind the traditional conveyor-belt manufacturing approach to achieve unsurpassed standards of flexibility and automation.