Sensational sensors

Technology is gradually taking over the automobile to the extent that it can virtually take over the task of driving. Modern luxury cars now contain myriad sensors that provide feedback to various systems top optimize both performance and safety in ways that were hardly imaginable a decade or two ago.

In addition to those that simply pertain to operating the engine and transmission, there are sensors in place that control a car's antilock braking system, yaw and steering sensors to provide information to the electronic stability control system and often others in the suspension to vary settings according to an auto's speed and steering and the underlying road surface.

While most operate more or less in the background, a number of automotive sensors are now being used to provide feedback directly to the driver. Perhaps the most common are the sonic-assist parking sensors that look like small discs embedded within the rear and, sometimes, front bumpers. These warn a motorist, through a series of beeps, when he or she is in close proximity with another vehicle or other obstruction at parking speeds. The more rapid the beeping becomes, the closer the car is to the other vehicle or object.

Going a step further, cameras are being added so motorists can actually see a rear-view bumper-height image on a small dashboard or rear-view mirror monitor to further make parking easier and safer. Some Nissan and Infiniti models take that concept several steps further with an Around View Monitor system that utilizes no less than four small cameras to give the driver a "top-down view" of the outside of the vehicle while parking.

Laser and radar sensors have also been added to monitor traffic. This was first introduced for Adaptive Cruise Control, a system that automatically controls both a vehicle's speed and its distance from cars in its path. While most only work at higher speeds, the most advanced of these systems can even operate in stop-and-go traffic. As this technology becomes more sophisticated, features are being added that will warn a driver about possible collisions when a car in front slows or stops suddenly or another object appears.

In many cars, such systems will simply pre-charge the braking system so it will automatically provide greater stopping force when the driver applies the brakes. At the other extreme Volvo's new City Safety system will automatically slam on the brakes to avoid hitting a stopped car or obstruction at speeds under around 18 miles per hour.

Now that radar and other sensors are in place in cars, manufacturers are finding more uses for them. For example, Ford's 2010 Taurus can be equipped with radar sensors in the front bumper and in both left and right rear quarter panels. The front sensor, says Steve Kozak, Ford's chief safety engineer, can see cars as far as 450 feet ahead in adaptive cruise control mode. It also has a collision-warning mode that can sense a possible collision 325 feet ahead and will activate a series of LEDs on the dashboard while sounding an alarm. While Ford's system won't activate the brakes automatically it includes a Brake Support function to provide harder and quicker deceleration once the driver takes the appropriate action.

Meanwhile, radar units installed on the car's side panels are utilized to warn a motorist of traffic approaching from either side when the vehicle is shifted into reverse, which can be particularly beneficial when backing out of a parallel parking slot, garage or alley.

For now, Kozak says, the radar can pick up large metal objects including cars and even motorcycles and, in some cases, shopping carts. However, it cannot read smaller and non-metallic objects such as bicyclists and pedestrians. That means drivers can rely on such technology only as supplements, but not as a replacement for what is otherwise the prudent practice of simply looking around.

Other technologies provide assistance while a motorist is changing lanes. Nissan, for example, has a system that uses a camera to keep an electronic eye on lane demarcations on the road and warn an inattentive driver if the car is drifting across them. Ford's radar-based system watches for vehicles in the driver's blind spot and gives a visual warning in the side-view mirrors and, if necessary, an audible alert to help avoid collisions while changing lanes.

Where is this technology headed? Kozak says vision-based systems are being developed and he expects to see them in place well before the end of this decade. This means we'll see smarter sensors that will have the ability to actually recognize and warn about potential collisions with anything from a bicyclist to an animal darting across the road.

Ford's goal, says Kozak, is to bring such safety technology to all its vehicles, not just the expensive ones. When this happens, there is the potential to dramatically reduce the number of traffic collisions that occur each year.