Mercedes‑Benz has introduced steer-by-wire on the refreshed EQS, becoming the first German automaker to deploy the technology in a production passenger car. The system replaces the mechanical steering column link with electronic control: driver inputs are interpreted by control units and sent to actuators that steer the wheels, while a model-based algorithm recreates steering feel and suppresses unwanted road vibrations.
Key features
- Steering architecture: Fully electronic steering signal paths with a redundant dual-path design and high-precision sensors and control units to maintain steerability if one path fails. In an unlikely total-system failure, lateral control remains via the 10° rear-axle steering and selective wheel-braking interventions through the ESP system.
- Driver experience: A flattened, more compact steering wheel improves visibility of the driver display and eases ingress/egress. Haptic and model-based feedback preserve intuitive, Mercedes‑Benz–character steering feel while actively eliminating undesired vibrations transmitted from road irregularities.
- Dynamics and usability: Variable steering ratios and close integration with rear-axle steering let the EQS combine sportiness, comfort, stability and maneuverability—making low-speed parking and high-speed stability both easier and more precise.
- Safety innovations: Because the compact wheel cannot brace an airbag against a closed rim, Mercedes developed a novel internal support and folding airbag architecture that controls inflation shape and deployment while meeting the brand’s unchanged restraint standards.
- Validation and options: The system has logged more than one million test kilometres across benches, tracks and public roads. Steer-by-wire is offered across all EQS powertrains and paired with the optional 10° rear-axle steering; traditional electromechanical steering remains available as an alternative.
Steer-by-wire is part of a broader “drive-by-wire” trend that decouples mechanical links and uses electronics to control vehicle subsystems. Unlike electric power steering (which still transmits torque mechanically), steer-by-wire severs the direct column-to-axle connection and relies on electronic control and actuators. Safety is typically achieved through redundancy—multiple sensors, parallel communication networks, duplicated actuators and fail-operational strategies—allowing compensation (e.g., torque vectoring or braking) if one component fails.
Past implementations and market trajectory include academic and concept demonstrators since the 1990s, aftermarket/up‑fit systems and a few production steps: Infiniti offered a steer-by-wire setup (with a clutch‑linked backup column) in the 2010s; several recent BEVs and luxury models have adopted rear-axle steer-by-wire paired with a conventional column, while a smaller set of vehicles pursue no‑column steer-by-wire. Mercedes‑Benz’s EQS rollout signals a new phase in mainstream premium adoption: applying full steer-by-wire in a production luxury saloon together with an airbag redesign and broad safety redundancy.
