ZF is equipping NIO’s electric flagship, the ET9, with its latest steer-by-wire system. The technology group is providing the steering wheel actuator for both steering control and feedback, as well as a redundant steering gear actuator and the necessary software. This enables the ET9 to operate without a mechanical link between the steering wheel and the front wheels. With the launch of its “Chassis Solutions” Division in early 2024, ZF now offers a full range of electronically controlled steering, braking, and damping systems. These, combined with ZF’s cubiX software, lay the foundation for the software-defined vehicle.
“We are supplying customers with the steering of the future. With our production-ready steer-by-wire steering system, we are launching the era of the software-defined vehicle. With an entire portfolio of innovative by-wire technologies, we are a sought-after supplier and a key driver of future-oriented chassis technologies,” says Dr. Peter Holdmann, Member of the Board of Management at ZF and responsible for the Chassis Solutions Division. “ZF is thus establishing itself as a technology leader in this area and giving car manufacturers such as NIO new freedom in terms of design, comfort, driving functions and safety.”
“At NIO, we are dedicated to delivering innovative breakthroughs that redefine the premium driving experience. Steer-by-wire technology is a crucial enabler of software-defined vehicles, providing enhanced comfort, superior dynamics, and future-proof capabilities,” says Danilo Teobaldi, Principal Chief Engineer at NIO.
“Our partnership with ZF, a global leader in high-quality automotive solutions, underscores our commitment to setting new industry standards as we introduce our smart EVs to the global market. From our strategic collaboration in 2022 to the industrialization of this technology, we’ve proven our ability to execute and deliver cutting-edge solutions. Together with ZF, we are shaping the future of intelligent, electrified mobility and raising the bar for the entire industry.”
In ZF’s steer-by-wire steering system, a mechatronic actuator between the wheels is the only source of steering power. There is no longer a mechanical connection between the steering wheel and steering gear. The steering commands are issued by a steering wheel actuator in the cockpit, which has a corresponding angle of rotation sensor. An electric drive – the so-called torque feedback unit – reproduces the natural steering feel and feedback from the road. The ZF system adjusts the steering ratio individually so that the ratio of the steering wheel angle to the wheel angle is optimally adapted at different driving speeds or situations.
It is also possible to develop new, more compact steering wheels that no longer require drivers to change their grip when parking. All in all, this leads to significantly better maneuverability, as the steering wheel angle is reduced when parking or during slow-driving maneuvers. Combined with ZF’s own AKC mechatronic rear-wheel steering, driving comfort also increases significantly in electric vehicles with an extended wheelbase. Driving pleasure is maintained – the steering feel can be adjusted from sporty and direct to comfortable and relaxed. And without a steering column, the driver’s safety is increased in the event of an accident.
ZF’s steer-by-wire technology is therefore a further development of electric power steering – ideally suited for electric and automated vehicles.
