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How Driverless Cars Will Work

Dawn of the Driverless Car
Anti-lock brakes, a standard feature in most cars, are a basic form of driverless technology.
Anti-lock brakes, a standard feature in most cars, are a basic form of driverless technology.
2008 HowStuffWorks

You can't just jump head-first into driverless cars. That's a recipe for driverless disaster, my friend. One of the earliest driverless cars was Stephen King's "Christine," remember, so let's all be grateful that idea didn't make it to market before the quirks had been worked out.

An early -- and non-murderous -- first step toward driverless cars came in the 1980s, and it's still with us today: anti-lock brakes (ABS, according to that terrifying light on the dashboard). Technically, anti-lock brakes do need the driver to step on the brake pedal in order to work, but they perform a function that drivers used to have to do themselves. When a car is braking hard and doesn't have anti-lock brakes, the wheels can lock up, sending the car into an out-of-control skid. In a car without anti-lock brakes, the driver has to pump the brake pedal to keep the wheels from locking up. With anti-lock brakes, the system does the pumping for you -- and it does it better and much faster than you ever could, thanks to speed sensors in the wheels.

About ten years later, manufacturers used those same sensors to take the next step toward driverless cars: traction and stability control. These systems are a step up the sophistication ladder from ABS. They use the sensors at the wheels to detect when a car might go into an out-of-control skid or roll over, and then they use ABS and engine management to keep the car on the road and the shiny side up. Unlike a driver, these systems can apply the brakes and increase or decrease power to individual wheels, which is often better than brakes or power being applied to all four wheels by a human foot mashing the brake pedal in a blind panic. See? Already your car is a better driver than you, and we're only at, like, 1995.