Hyundai Motor and Kia have revealed two new innovative wheel and tire technologies focused on EV design and snow driving, respectively.

The first is a new wheel drive system for electric vehicles (EVs), which the partners claim will open up new vehicle design possibilities. It integrates drive components into the wheel to deliver better efficiency, power, and durability without impacting ride comfort for improved packaging potential and passenger space, greater driving range, and PBV (purpose-built vehicle) development.

The second new technology is a new snow chain-integrated tire system for winter driving conditions. It uses shape memory alloy inside a wheel and tire to act as a snow chain at the touch of a button.

 

Uni Wheel drive system improves packaging

The Uni Wheel, short for Universal Wheel Drive System, is designed to improve available space inside an EV by moving the main drive system components to the vacant space within each wheel hub. Check out the video here.

In internal-combustion-engine vehicles, power is transmitted from the engine through the transmission to the wheels via driveshafts and constant velocity (CV) joints. In EVs, the engine and transmission are replaced by a motor and reduction gear, but the final method of transmission to the wheels is the same.

The Hyundai/Kia system enables a flat-floor configuration by moving an EV’s reduction gear inside the wheel hub, locating a compact individual motor close to each wheel, and reducing the length of each driveshaft. It frees up significantly more interior space than conventional drive systems, enabling future mobility products such as PBVs (purpose-built vehicles) 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. “We will perfect the technology so that customers can experience mobility in a completely different and new way.”

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 then engages the pinion gears to rotate the ring gear. This is connected to the wheel to drive the vehicle.

Its pinion gears are connected to form two linkages. This multi-link mechanism enables Uni Wheel’s multi-axis movement to allow for a range of suspension articulation.

Conventional drive systems using regular CV joints suffer from a decrease in efficiency and durability as the angle of driveshaft deflection increases when traveling over undulating surfaces. Uni Wheel can transmit power with almost no change in efficiency regardless of wheel movement, ensuring high durability and ride comfort, according to the company.

The system can also work with electronic air suspension systems that adjust vehicle ride height for varying driving situations, to stabilize the vehicle on rough roads or improve power and stability for high-speed driving.

 

Integrated snow chain and tire for better winter traction

Not content with reinventing just the wheel, the Hyundai/Kia duo announced earlier this week a snow-chain-integrated tire technology that uses shape-memory alloy modules located inside the wheel and tire. These modules protrude to act as a snow chain when an electrical signal is received.

Hyundai demonstrated the new technology in a video and said it would consider mass production of the system after further technological development, durability and performance tests, and regulation reviews.

“This innovation, which will hopefully be introduced on Hyundai and Kia vehicles someday, reflects our commitment to turning advanced technologies into real-world solutions that benefit customers,” said Joon Mo Park, head of the Advanced Chassis Development Team at Hyundai Motor.

The snow chain-integrated tire technology consists of a wheel and tire assembly that features radial grooves at regular intervals like a pizza, with modules made of shape-memory alloy inserted into these channels. The technology takes advantage of the alloy’s ability to return to its original shape when an electric current is applied.

During normal driving, the shape-memory alloy located inside the wheel is compressed into the shape of the letter “L” and does not contact the road surface. When the driver activates the function, an electric current is applied, causing the alloy to revert to its original profile, the material forming a “J” shape, pushing the module out of the tire to contact the road surface, improving grip, stability, and safety in snowy conditions.