Nissan Develops Fully Electric Steer-By-Wire System, Will Go On Sale Next Year

Electrically assisted power-steering setups haven’t yet fully replaced traditional hydraulic assist in modern vehicles, but even that relatively new tech soon will be outmoded, thanks to Nissan. What could be more high-tech than electric power-steering assist, you ask? Fully electric power steering, with no mechanical link between the steering wheel and the steering rack tied to the front wheels—steer-by-wire, if you will. Nissan has developed such technology and plans to put it in a production car within a year. Wait, what?

That’s right, Nissan has transferred a concept long used for throttle applications—drive-by-wire—to the steering controls; the company is calling the tech Independent Control Steering. In this case, drivers make steering inputs, and those inputs are cycled through several redundant (just in case!) computer modules before being sent to the electric motor actuating the steering rack—no mechanical steering column needed. The traditional column may be superflous, but Nissan’s system incorporates one anyway; the unit can connect to the steering rack via an emergency clutch so that drivers can maintain steering control should a total electrical meltdown occur.

Interestingly, Nissan’s thrust to jump from electric steering assist to full-electric operation has little to do with fuel economy. (Many automakers make the switch from hydraulic power assist to electric because electron-enhanced steering racks sap less engine power during operation, resulting in better fuel economy.) Instead, Nissan claims its steer-by-wire system actually improves the driving experience. Not only do driver inputs reach the steered wheels quicker, but feedback from the road can be analyzed—again, via the computers—and kicked back to the steering wheel quicker than typical steering systems. Of course, the key word there is “analyzed;” any and all “feedback” is heavily filtered and recreated at the steering wheel. Nissan, for its part, says testers in a blind back-to-back comparison with a regular steering setup thought the fancy new system was better.

We’ll wait until we drive an actual car with this actual system before coming to any conclusions of our own, and for now will take Nissan’s claims with a small shovelful of salt. That’s because, generally, even regular electrically assisted steering systems have had a hard time breaking through to hydraulic levels of feedback and feel. Further muddying Nissan’s apparent sporting pretensions with its new tech is the other motivation for implementing steer-by-wire: the ability to tune out unwanted road feel. Allow us to explain what this means: Road feel is appreciated when cornering or maneuvering a car hastily; road feel like steering-wheel jiggle and shake over pockmarked pavement while driving in a straight line isn’t as appreciated.

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Nissan says steer-by-wire can detect such potential bump-steer and wobble via the electric-steering actuator itself and compensate accordingly. While we agree that some road feel is best left on the road and not felt in a driver’s hands, any system that decides what is good or bad feel raises red flags in our book—a computer couldn’t possibly get something like this “right” every time, potentially filtering out good steering vibes along the way. Upping the car-knows-best factor is the system’s corresponding windshield-mounted camera, which scans the road ahead for lane markers and feeds the info to the steering actuator so that it can effectively center the car within a lane—without any input from the driver. Nissan points out that this function differs from lane-keeping assist, which counters drifting with braking and steering inputs to keep a car from drifting out of its lane.

So when can we see steer-by-wire on the street? According to Nissan, the tech will be available on a road car within a year. It isn’t presently clear whether this timeline applies to the U.S. or which car it will arrive installed in. At a demonstration of the tech in Japan, the electric-steering system was installed on an Infiniti G37S. A new G arrives next year as a 2014 model, and would be an ideal candidate for such a high-tech and supposedly sporty piece of hardware.

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Mike Hailwood Mika Häkkinen Bruce Halford Jim Hall Duncan Hamilton