Adaptive cruise control has been a standard feature for decades, but its core hardware is surprisingly simple: a radar sensor behind the grille and a camera near the rearview mirror. The system measures the gap to the vehicle ahead and adjusts speed, but automakers are clear that it is not a collision avoidance system.
According to Engadget, the limitations are significant. Toyota, Volvo, and Honda warn against using the feature in rain, fog, snow, heavy traffic, sharp bends, or steep hills. Volvo says its radar's detection is reduced in downpours and can be late spotting a car that cuts in close. The system may not register stationary vehicles, so a stopped car in the lane might not be detected.
Despite these limits, studies suggest drivers place too much trust in the technology. An IIHS and MIT AgeLab study found that drivers with lane-centering were more than three times as likely to use a phone or console by the end of a month, and 17 times as likely to drive with both hands off the wheel. An earlier IIHS study found adaptive cruise users were 24% more likely to speed on highways.
Automakers are trying to improve the experience with map data, as in Ford's BlueCruise, or machine learning, as in Hyundai's Smart Cruise Control. But the hardware has largely plateaued; Bosch's long-range radar already saw 250 meters in 2014 and its successor sees 530. The business challenge is managing consumer expectations while these systems remain limited to favorable conditions.