We've used steering wheels to guide our cars for more than a century, and it's worked out pretty well so far. They're simple and intuitive, and it doesn't seem there's much room for improvement---at least until autonomous vehicles make them moot. But that didn't stop Saab from thinking it had a better idea.
Now, Saab was always quirky in a cool way. There's that whole ignition on the floor thing, and how can you not like a sexy fiberglass two-seater with a V4 engine? But even Saab was waaaaay out there when it considered a joystick, of all things, an ideal control mechanism for steering a car. Perhaps it had something to do with the company's history of building jets.
Anyway, back in the early '90s, the safety-obsessed Swedes designed a version of the venerable Saab 9000, nicknamed the Prometheus, with no steering wheel. Instead, there was a sort-of joystick in the center console that you'd twist left and right to turn the car. From a purely safety perspective, this seems like a good idea. When you get into a car accident, there's a big, hard, round thing right there to smash your noggin on. Even with an airbag, it's still not ideal. Remove that, and you get a nice, clean, wide-open dashboard. Fewer things to smash your head on, more room between you and the dashboard, and you've still got an airbag to protect you.
So that's great, but how was the thing to drive? Not great.
It turns out that the steering wheel is an excellent way to steer a vehicle, and really tough to improve upon. That's why they've been used on ships for centuries. The key to controlling any vehicle is to make smooth adjustments to keep it going where you want to. Steering wheels allow this. Most turn 1,260 degrees---3.5 turns---from lock-to-lock, that is, from all the way left to all the way right. That allows the driver to make very precise corrections to get the car pointing the right way, or quickly make big corrections to, say, avoid hitting something.
Saab's joystick, however, turned 180 degrees lock to lock. This meant that even small adjustments to the joystick led to big changes in where the car was pointed. Not optimal. And keeping your hand on a joystick gets tiring. A steering wheel provides a natural place to rest and support your hands and arm, while a joystick does not. You have to hold your hand up yourself, which doesn't sound like a big deal until you've done it for awhile. (Yes, yes, fighter jets are controlled with a stick. But you can release it without bad things happening, and you have autopilot as well.) A potential production model was to have two joysticks, one for each hand, to reduce fatigue.
Unlike a standard car, which uses mechanical and hydraulic linkages to connect the steering wheel to the wheels, Saab's joystick used electrical signals sent to a computer to turn the wheels. It's common in aircraft (Saab: Born from jets!), where it's called fly-by-wire, but steer-by-wire hasn't taken off in cars (even if throttle-by-wire is increasingly common.) So far the Infiniti Q50 is the only production car using steer-by-wire, and it has a conventional steering wheel.
The Prometheus was part of a broader pan-European program that drew funding and expertise from governments, automakers and suppliers to make cars safer, cleaner and quieter. The joystick-Saab was just one idea; other projects included things like adaptive cruise control and IR camera systems that identify things in low light or poor conditions.
Although those technologies are appearing in high-end cars, joystick steering is but a footnote in automotive history. Sorta like Saab.
Have a crazy invention or whopping failure you want us to cover? Email alex_davies@wired.com and jlgolson@gmail.com and we’ll check it out.
