How Does a Steer-by-Wire System Work?

The “Steer-by-Wire” technology is revolutionizing the way vehicles are steered by eliminating the mechanical link between the steering wheel and the wheels.

Unlike traditional systems, where a steering column transmits the wheel movements to the rack via a series of mechanical components, Steer-by-Wire, or electronically controlled steering, relies entirely on sensors, actuators, and software. In short, electronics replace mechanical parts.

In a vehicle equipped with this technology, an actuator located at the steering wheel converts the driver’s movements into electronic signals. These signals are then transmitted to another actuator at the wheels, which adjusts their angle to follow the commands. An electronic control unit monitors this process in real time, ensuring precise and smooth responses.

ZF at the forefront of Steer-by-Wire

ZF, a major player in the field, has recently begun serial production of this Steer-by-Wire technology by equipping the NIO ET9, a high-end electric vehicle. The system includes an actuator for the steering wheel, a redundant actuator for the rack, and associated software. Together, these components allow for adjusting the steering ratio based on speed and driving conditions, providing increased maneuverability during slow maneuvers or a sporty feel on the highway.

Among the advantages, Steer-by-Wire eliminates the steering column, reducing the weight of related components and, of course, the injury risks in case of collision. It also paves the way for new interior designs, such as compact or removable steering wheels. Additionally, the system can be combined with other innovations like active rear-wheel steering to further enhance comfort and driving dynamics.

However, this advancement raises questions. Electronic redundancy is crucial to avoid failures, and software reliability becomes a major concern. While removing hydraulic fluids and mechanical parts simplifies maintenance, it demands full trust in the technology.

And you, are you ready to entrust your safety to a car without a mechanical link between the steering wheel and the wheels?