Steer-By-Wire Technology: A Game-Changer in Automotive Innovation
Steer by wire technology is rapidly making its way into showrooms of various automotive brands, marking a significant shift in the way vehicles are designed and operated. Mercedes, a pioneer in automotive technology, will be the first German manufacturer to introduce this cutting-edge technology with a ZF-developed system that eliminates mechanical connections between the driver and the road wheels, relying instead on sensors and electric actuators.
Joining the ranks of innovative manufacturers, Nio is equipping the ET9 with a ZF steer-by-wire system, while Lexus is set to launch the technology in the RZ model next year. Bosch, through its joint venture Bosch Huaya Steering Systems, has secured three Chinese customers for its steer-by-wire system, with production set to commence soon.
Once considered a forbidden fruit in the automotive industry, steer-by-wire technology gained legal recognition in Europe with the introduction of UNECE Regulation 79 in 2003. Safety is a top priority in Mercedes’ system, with duplicated controls ensuring that if one electronic link fails, the other will seamlessly take over. Redundancy measures extend to dual electronic signal paths, duplicated power supplies, and hardware actuators, guaranteeing fail-safe operation.
In the rare event of a complete system failure, alternative control mechanisms such as rear-axle steering and individual wheel braking through ESP can still maintain vehicle control. The Mercedes steering feedback unit (SFU) transmits the driver’s inputs electronically to the steering rack unit (SRU), which executes the steering commands without the need for a mechanical connection.
Calibrating steer-by-wire systems is a meticulous process, with each manufacturer customizing the technology to suit specific vehicle models. Mercedes, for instance, has conducted extensive bench testing and real-world trials, totaling over one million kilometers, to ensure optimal performance and safety.
Nio highlights the packaging and design advantages of steer-by-wire technology, allowing for customizable steering wheel angles and feedback levels for precise control. The ET9 system boasts features such as a rectangular steering wheel for improved instrument visibility and full lock achieved with minimal wheel movement.
Furthermore, the system filters over 80% of road vibrations for a smoother driving experience, and the telescopic steering column offers enhanced adjustability. Nio even hints at a Game Mode option, catering to the preferences of the Chinese market and showcasing the versatility of steer-by-wire technology.
