ZF’s Steer-by-Wire Innovation Powers NIO’s ET9 Electric Vehicle
With its state-of-the-art steer-by-wire system, ZF is outfitting NIO's premier electric vehicle, the ET9. The technology group provides the steering wheel actuator for both steering control and tactile feedback, along with the redundant steering gear actuator and its corresponding software. Consequently, the Smart Electric Executive Flagship model operates without any mechanical linkage between the steering and front wheels. Since establishing its Chassis Solutions Division in early 2024, ZF has developed an extensive range of purely electronic steering, braking, and controlled damping systems. Integrated with ZF's cubiX software, these technologies underpin the software-defined vehicle.
Dr. Peter Holdmann, a ZF Board of Management member responsible for the Chassis Solutions Division, comments, "We are equipping our customers with tomorrow's steering technology. Our production-ready steer-by-wire system marks the beginning of the software-defined vehicle era. With our comprehensive suite of innovative by-wire technologies, ZF is a preferred supplier and a pivotal force in advanced chassis technologies. We solidify our leadership in this field and offer car manufacturers like NIO unprecedented design freedom, safety, comfort, and functionality."
Danilo Teobaldi, Principal Chief Engineer at NIO, states, "At NIO, we are dedicated to pioneering innovations that transform the premium driving experience. Steer-by-wire technology is crucial for developing software-defined vehicles, providing superior driving comfort, unyielding dynamics, and forward-looking technology."
"Our partnership with ZF, a globally acclaimed leader in high-quality automotive solutions, demonstrates our commitment to setting new industry standards by advancing our smart electric vehicles worldwide. Since our strategic alliance with ZF began in 2022, we have successfully industrialised this technology, showcasing our capability to deliver innovative solutions. Together, we are defining the future of smart and electrified mobility, establishing new industry benchmarks," adds Teobaldi.
ZF's steer-by-wire system features a mechatronic actuator between the wheels as the sole transmitter of steering inputs, eliminating any mechanical connection between the steering wheel and steering gear. Steering commands are managed by a steering wheel actuator in the cockpit, equipped with an angle of rotation sensor. The torque feedback unit replicates the natural steering feel and road feedback in an electric drive. The system tailors the steering ratio according to varying driving speeds or conditions, offering optimal adaptability.
This technology paves the way for developing new, more compact steering wheels that negate the need for drivers to alter their grip when parking. This substantially improves manoeuvrability as the steering wheel angle decreases for parking or slow-driving manoeuvres. Combined with ZF's AKC mechatronic rear-wheel steering, the system significantly enhances comfort in electric vehicles with longer wheelbases. The system maintains driving pleasure with an adjustable steering feel that ranges from sporty and direct to relaxed and comfortable. Furthermore, the absence of a physical steering column increases driver safety in accidents.
As a continuation of electric power steering development, ZF's steer-by-wire technology is ideally suited for electric and automated vehicles and is already in series production with another leading global car manufacturer. Customer orders for the steer-by-wire system have been secured in Europe.
"The series application validates our strategy's success," Holdmann explains. "With a full product portfolio of hardware and software solutions for controlling vehicle motion in vertical, lateral, and longitudinal dynamics, we offer our customers comprehensive system expertise from a single source, actively driving the shift towards software-defined vehicles."
In January 2024, the technology group amalgamated its Active Safety Technology and Car Chassis Technology divisions into a unified powerhouse. This merger has positioned ZF as a formidable industry force, maximising the potential of future chassis business and continuing its role as an innovation leader.
Following this new divisional structure, ZF announced a significant order for brake-by-wire systems at the year's start: nearly five million vehicles from a prominent global manufacturer will feature ZF's electromechanical braking technology.
With the most extensive array of by-wire technologies, ZF is at the forefront of developing and industrialising modern chassis systems that eliminate the need for mechanical connections or system fluids.
