In Steer-by-Wire steering, the wheels are turned by a mechatronic actuator. There is no mechanical connection between the steering wheel and the steering mechanism.
Steering commands are issued by the steering wheel actuator in the cab, which has a corresponding steering angle sensor. The electric actuator - the so-called torque feedback unit - reproduces the sensation of feedback on the steering wheel. The ZF system individually adjusts the steering gear ratio, so that the ratio of steering wheel angle to wheel angle is adapted to different driving speeds or situations.
ZF calls these advantages Steer-by-Wire:
- Steering flexibility: reducing the steering angle at low speeds makes parking and manoeuvring easier.
- New design possibilities: compact steering wheels can be created that do not require changing grip during parking.
- Rear steering: in combination with the ZF AKC (Active Kinematics Control) rear-wheel steering system, comfort is improved in electric vehicles with a long wheelbase.
- Safety: the absence of a steering column reduces the risk of injury in the event of an accident.
Steer-by-Wire steering technology thus represents a further step in the evolution of electric power steering.
Steer-by-Wire is designed specifically for electric and automated vehicles. Besides NIO, another unnamed major car manufacturer is already using this technology in series production. In addition, ZF has received an order from a European automaker.
Source: ZF
