Driver Assistance Systems

By Zac Estrada
Last Updated 06/01/2015

Technology that warns or prevents crashes isn't the future, it's reality. Today, there are numerous vehicles on the new and used markets that use cameras, radar and sensors to stop mishaps that bend metal, break glass and injure people.

But it's important to understand what these various systems are capable of. Brand names are thrown around but the actual limits of these technologies can be muddied. Here's an outline of the various safety features emerging on vehicles and what they can do.

Alerts

Features like blind spot monitoring, lane departure warning and forward collision warning have begun to appear on a wide range of vehicles from different price points. These tend to use either cameras or sensors mounted around the car to determine what vehicles are around you, or where your car is in relation to other objects. Beginning around 2007, these features were introduced on luxury cars and have now expanded to mainstream cars. In fact, you can even find them on compact cars such as the Dodge Dart and Mazda3.

Blind spot monitoring is mounted in (or near) the sideview mirrors to alert you via a light if a car is detected alongside you, which is where you might hit it if you decide to make a lane change. Most systems emit an audible alert if you actually try to make that lane change with a car in your blind spot.

Lane departure warning works in a similar way, using a light and/or a sound to warn if you are drifting over the painted lane markers on a highway. These systems tend to work at speeds above 40 mph.

Some cars feature forward collision warning that's based off of a radar or camera. These systems sense if you're going to hit the car in front of you if you keep traveling at your current speed without braking. Again, a light or an audible alert will warn you of an impending collision so you can plant your foot on the brake pedal. In some vehicles, the brakes are primed to give more force than you would normally get in a standard stopping situation.

Avoidance

At the next level are systems that intervene using the car's controls when objects are detected.

The next step are radar and camera systems that trigger inputs from the steering or brakes to attempt collision avoidance altogether. Both of these features are still typically found on luxury cars.

Automatic emergency braking is one of the most important of these features. At speeds typically 25 mph and below, sensors on the car take that forward collision warning a step further and will attempt to bring the car to a stop. Volvo has made this feature standard under the City Safety moniker on all of its new cars from the 2014 model year, though it became standard on the XC60 crossover in 2009. The best of these systems are often teamed with radar-guided cruise control, and can bring the car to a complete stop and then move forward as traffic dictates.

Lane keeping assist is a feature being introduced to more vehicles every year. It takes the blind spot and lane departure warnings a step further by using steering and braking to push the car into the correct position and stop it from drifting out of the lane or into the path of another car.

Night Vision

In its current state, night vision is a relatively new setup that is primarily useful for driving around poorly lit roads where visibility is tenuous at best. A camera mounted in the front of the vehicle can use infrared technology to make objects much more visible from a distance. It can also detect people who might be in the roadway and alert you if your vehicle may come into contact with them.

From 2014, systems found in various Audi, BMW and Mercedes-Benz vehicles can have animal detection systems in addition to pedestrian detection, which can prevent incidents such as collision with deer and other common crashes in rural areas.

Night vision cameras, however, are expensive additions that were often combined with expensive packages on high-end vehicles like the Audi A8 and BMW 7-series. If you're looking for this system, be prepared to spend a lot of money, even on the used market.

What You need to Know

Both the National Highway Traffic Safety Administration (NHTSA) and the Insurance Institute for Highway Safety (IIHS) have guides to determine the most effective safety technologies available in cars today. Certain automakers use more comprehensive systems than others, too, so it's worth checking the ratings on the crash avoidance technologies that each vehicle offers.

Also prepare to spend time seeking these features out. While new models are more frequently being equipped with advanced safety technologies, the take rate for them has been somewhat low up until now, meaning models on the used market may be harder to come by.

But as you prepare for your next vehicle purchase, keep these in mind if you want the added security of electronic intervention.