Even though Infiniti was the first manufacturer to bring steer-by-wire to a production car almost 10 years ago, that system was optional, and you could still opt for a conventional setup with a mechanical link between the helm and the wheels. It’s also offered as an option in the Toyota bZ4X and Lexus RZ450e.
The first true steer-by-wire production vehicle is the Tesla Cybertruck, and driving one takes a bit of getting used to since you have to apply a lot less lock than in a traditional setup, and it also has a variable ratio. This means it’s not very sensitive off-center, but the more you turn the wheel, the lock you apply increases progressively. This ratio also varies depending on the driving speed.
The Tesla Cybertruck is steer-by-wire only
Unlike other manufacturers that have offered steer-by-wire as an option in their vehicles, for the Tesla Cybertruck it’s the only available setup and it makes for an unusual driving experience that takes a bit of getting used to.Â
One of the most unusual characteristics of the Cybertruck with its steer-by-wire system is that you can turn the steering wheel when the vehicle is powered off, and none of the wheels will turn. Do the same after powering on the Cybertruck, and you will see both its front- and rear-wheel steering racks working.
Steer-by-wire is definitely still a novelty in cars, although several manufacturers have announced plans to introduce it in production cars in the next few years—Mercedes is rumored to give its next S-Class steer-by-wire. If you’ve ever wondered how a system like this works, this video by Sandy Munro of Munro Live—the latest part of his Tesla Cybertruck teardown series—should shed some light. Sandy and his team first demonstrated how it works, then they extracted the front and rear subframes from the truck to get a better look at how they work.
They also show the steering column, which looks very different from any steering column you may have seen before. It stops where you would expect it to continue with a shaft that links to the steering rack, and it just has electronics, servos and wires that enable it to have a variable ratio. The steering rack (which interestingly appears to be supplied by ZF) has two motors for redundancy, so if one malfunctions, the backup motor can take over and keep the steering system alive.
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