Carmakers rapidly adding semi-autonomous features

Fully self-driving cars are a few years into the future. But some of the technology that will make them possible is already here.

Automakers are rapidly adding radar- and camera-based systems that can keep a car in its lane, detect pedestrians and brake automatically to avoid a collision. For now, they work with a driver behind the wheel, but eventually, versions of these systems will likely power self-driving cars.

Semi-autonomous features used to be confined to luxury cars, but they’re quickly migrating to mainstream brands as technology gets cheaper. Toyota, for example, will offer automatic braking, pedestrian detection and lane departure warning for just a few hundred dollars on all of its vehicles by 2017.

Automakers are also being nudged to add these features by safety advocates like the Insurance Institute for Highway Safety, which gives its top crashworthiness rankings to vehicles with crash prevention technology.

Joseph Gerardi, a communications engineer from Centereach, New York, recently bought a 2015 Nissan Murano specifically for its semi-autonomous safety technology. As part of its $2,260 technology package, Nissan offers emergency braking and adaptive cruise control. The package also has forward collision warning, which uses radar to monitor both the car ahead and the car in front of that one.

“We just wanted to get the safest thing possible,” he said.

The array of semi-autonomous features now offered on cars can be bewildering. Here are some of the most common:

■Adaptive cruise control: Regular cruise control, which has been around for decades, can keep the car at a set speed on the highway. Adaptive cruise control maintains a set speed as well as a set distance from the car in front of it, and it can slow down or speed up automatically. It started appearing on luxury brands like Mercedes and Lexus about a decade ago. Now, it’s available on less expensive models, like the Mazda3 and Chrysler 200.

■Lane keeping: Lane departure warning systems beep or vibrate if the driver leaves a lane. Camera-based lane-keeping systems actually steer the car back into the lane automatically. They have their limits; they might not work in snow or at other times when lane markings aren’t clearly visible. Lane keeping started appearing on the market in 2014. The Ford Fusion Titanium has it as a $1,200 option, and the Jeep Renegade Limited as a $995 option.

■Emergency braking: Some forward collision warning systems beep or flash lights to warn the driver if they detect an object. More advanced ones warn the driver and, if the driver doesn’t react, apply the brakes. The systems may either bring the car to a complete stop or slow it enough to mitigate damage. The technology, introduced in 2008, is recommended by the federal government. It’s standard on the Volvo XC90 SUV, which can even brake automatically as the driver is turning into an intersection. Others include that the Subaru Outback, as part of the $3,090 EyeSight package, and the Toyota Camry XLE, as part of a $2,570 technology and navigation package.

■Self-parking: Self-parking systems can find a spot and automatically park in a parallel or perpendicular spot. The systems, on the market since 2008, are now on many mainstream vehicles. It’s a $395 option on the Ford Focus Titanium.

■Highway autopilot: Single-lane highway autopilot is basically just a combination of adaptive cruise control and lane-keeping. It helps keep the car centered in its lane at highway speeds, allowing the driver to cruise with minimal effort. Mercedes, Infiniti and Audi are among those whose systems work in tandem on the highway.