American Express-Savings
For lane departure warning, the system will light up a lane line on the display if you are drifting over the lane line in the road. The lane line icon will light up on the side of the display corresponding to the line you are drifting over. Activating the turn signal for the lane line you are crossing defeats the warning. Along with the lane line icon, the speakers emit a rumble strip sound, which serves as an audible warning.
Performance
In our testing, the Headway Monitoring feature did an excellent job of recognizing cars ahead of us, while not getting confused by oncoming traffic, cars in other lanes, or turns. We found the time display particularly useful. As we moved onto higher speed roads, the distance between our car and the one ahead changed, but the number of seconds remained the same. At slower speeds, the distance decreases.
In moderate to heavy traffic on the freeway, we usually had the green icon lit, which still left a generous amount of space between cars, an invitation for other cars to cut in. During city driving, we often had the car icon lit amber or even red, as it is unrealistic in heavy traffic at moderate speeds to leave a big gap in front.
We were impressed that the AWS-4000 could tell when we were slowing and getting ready to stop behind another car at a traffic light, and didn't sound off its warning. Likewise, a couple of times cars pulled out from the curb abruptly into our path, and we appreciated the warning sound from the unit. We did notice that the system won't recognize motorcycles, and anything smaller, of course.
However, our main complaint is that the collision warning is too loud. There is a volume control, but even at its lowest level it is ear-splitting. That loud warning is especially annoying when you are aware of the car in front and already getting ready to hit the brakes.
Lane Departure Warning was less effective, although this was due somewhat to poorly painted lane lines. With a boldly or freshly painted lane line, either solid or dashed, the AWS-4000 lit up its lane line icon and made its rumble strip sound from the left or right speaker, depending on which side the lane line was on. But it didn't register faded lane markings.
Strangely, the rumble strip audio warning is too quiet, even at maximum level. People are likely to drift when they are falling asleep, so the warning should be audible enough to wake a person up. It was impressive that the system knew which turn signal was on, and would still sound off if you had the right signal on but crossed the left lane marking.
In sum
Because it is an installed product, Mobileye doesn't list a retail price. You have to go to a professional installer to get the system. But we understand it is not cheap. The AWS-4000 offers good potential for fleet applications if its installation costs are offset by insurance reductions. Automakers could partner with Mobileye as an OEM (original equipment manufacturer) and install its technology at the factory, possibly using an instrument panel display instead of the pod tacked to the dashboard.
