Advanced Driver Assistance System (ADAS)
calibration service. Car keys.

Adaptive cruise control (ACC) is an intelligent form of cruise control that slows down and speeds up automatically to keep pace with the car in front of you. The driver sets the maximum speed — just as with cruise control — then a radar sensor watches for traffic ahead, locks on to the car in a lane, and instructs the car to stay 2, 3, or 4 seconds behind the person car ahead of it (the driver sets the follow distance, within reason). ACC is now almost always paired with a pre-crash system that alerts you and often begins braking.

Adaptive cruise control is also called active cruise control, autonomous cruise control, intelligent cruise control, or radar cruise control. This is the case because distance is measured by a small radar unit behind the front grille or under the bumper. Some units employ a laser, while Subaru uses an optical system based on stereoscopic cameras. Regardless of the technology, ACC works day and night, but its abilities are hampered by heavy rain, fog, or snow.

Lane departure warning alerts you that your car is about to veer out of lane and warns you to get back into lane. That's the basic idea, but there are several versions of the technology available now, including ones that react and steer away from the lane edge and even proactively keep the car centered. All forms of lane departure warning employ a low-cost camera mounted in the windshield near the rear view mirror that continuously watches the striped and solid lane markings of the road ahead. It is part of the circle of safety, the three most common and useful driver assists: protecting you to the front (adaptive cruise control and forward collision warning), side (lane departure warning), and rear side (blind spot detection).

How it works: windshield camera tracks lane markings

The most common LDW system is a camera mounted high up in the windshield, often as part of the rear view mirror mounting block. It captures a moving view of the road ahead as much as 150 feet ahead. The digitized image is parsed for straight or dashed lines — the lane markings. As the driver, you're supposed to center the car between the two lines. As the car deviates and approaches or reaches the lane marking, the driver gets a warning: a visual alert plus either an audible tone, a vibration in the steering wheel, or a vibration in the seat. If the turn signal is on, the car assumes the driver is intentionally crossing over the lane, and there's no alert.

Then there's lane keep assist. When the car reaches the lane marking, the car nudges itself away from the marker, sort of like bouncing off the walls in Pac-Man. Sometimes the steering change is effected by braking the opposite front wheel and the car pivots back into the lane. The car can also move you back by turning the steering wheel. In either case, the driver can easily overcome the car's intentions by turning the wheel. It doesn't require superhuman efforts. If you read a story about a car that fought the driver for control of the wheel, it's either urban legend and untrue. The driver was so startled he or she presumed the car's steering was more powerful than it really was, or someone pretty clever has developed an amazing hack and we're in bigger trouble than we thought. But that hasn't happened yet.

Car night vision, now that it can reliably detect and alert you to pedestrians, cyclists and deer beyond the reach of your headlamps, is well worth considering when you're looking to buy your next car. The newest and best systems employ algorithms that determine whether an infrared hot spot is a living, moving thing near the roadway, then swivels a headlamp element to alert the driver — and the person or animal.
How passive night vision works: long range, simpler image

The Audi night vision sensor, hiding behind the grille
Night vision systems use an infrared sensor typically in the grille to look for warm objects in the roadway. The sensor is a video camera that captures the infrared spectrum just above visible light. The sensor outputs the moving image to a dashboard display. Increasingly, that's coupled with sophisticated algorithms that detect humans and large animals, and most recently, that sound an alert. This is the case for all night vision technologies

The Around View Monitor is a support technology that assists drivers to park more easily by better understanding the vehicle's surroundings through a virtual bird's-eye view from above the vehicle. The Around View Monitor helps the driver visually confirm the vehicle's position relative to the lines around parking spaces and adjacent objects, allowing the driver to maneuver into parking spots with more ease.

Technology Functionality
The Around View Monitor processes video from four cameras, displaying the composite footage on the screen as if there is a single birds-eye view camera right above the vehicle. This makes parking much easier.

Early on in Drivers' Ed, you were taught to look over your shoulder before changing lanes because side view mirrors don't see everything. What you may miss in a quick glance is what blind spot detection picks up. This driver assistance technology senses cars coming up in your blind spot behind or alongside you, and if your turn signal is on, it alerts you not to change lanes. You're warned by a flashing light on the side view mirror and then a beep or steering wheel vibration. If you're not planning to change lanes (there is no turn signal on), the warning light glows steadily but doesn't flash and there's no audible alert.

Blind spot detection is a key technology among driver aids that provide 360 degrees of electronic coverage around your car, whether you are at speed or moving slowly. This circle of safety also includes adaptive cruise control, lane departure warning, rear and front parking sonar, the rear traffic alert, and parking cameras (ranging from rear-only through four cameras providing a birds-eye view of the car as you snake into and out of tight spaces). Some driver's aids make you safer, especially late on a long drive, and some earn back their cost when you don't crumple a fender, where the insurance deductible costs more than the device.

Rear Collision Warning (RCW) is advanced safety technology that scans the area behind your vehicle and alerts you of a potential oncoming collision. Being rear-ended is one of the most common types of collisions. Because you have your eyes on the road ahead of you, it can be almost impossible to see a collision about to happen behind you.

That's why Volvo created the radar-based Rear Collision Warning system to act as a set of eyes at the rear, and help prevent rear-end collisions. If a vehicle approaches from behind and the system calculates that there's a risk of collision, it helps alert the driver in the approaching vehicle behind by flashing your hazard lights at a high rate. And if a collision still can't be avoided, the Rear Collision Warning system tensions the front safety belts just before the impact. To further help reduce the strain on the occupants at the impact the system also activates the brakes if your car is at standstill.

Originally designed for military use, the head-up display (HUD) places important information (such as the current speed, and turn-by-turn navigation directions) right in the driver's line of sight. It helped fighter jet pilots stay focus at neck-snapping speeds, and it can play a big role in eliminating distractions from your daily commute. Some systems project information onto the windshield, while others show it on a separate screen usually attached a device placed on the dash.

HUDs are becoming increasingly common in all types of new cars, ranging from the Mazda3 to the BMW 7 Series, but you don't have to trade in your older model just to get one. Several aftermarket solutions let you modernize your current ride, whether you prefer an affordable device or a high-end product with a price tag to match. To make your decision easier, we've singled out some of the best on the market.