Collision avoidance and mitigation systems
Collision avoidance systems take much of the same hardware used in active cruise control and use it for a different purpose -- avoiding collisions in all types of day-to-day driving.
Much like adaptive cruise control, these systems scan the road ahead for obstacles. But instead of being used only when turned on at highway speeds, these systems are constantly operating and may sound alarms, boost brake sensitivity, and tighten seat belts to help prevent or reduce the effects of a collision.
Some systems can take even more drastic actions, including applying a vehicle's entire braking power to avoid a crash, Carlson says.
"It goes from really just an enhanced kind of cruise control braking, where you are still at speed and you are just kind of maintaining a safe distance, to actually kind of the safety-critical braking," Carlson says.
That's an important distinction, says David Good, director of the Transportation and Research Center at Indiana University. Unlike active cruise control, which is intended as a convenience, the kinds of calculations and decision-making these systems have to do to work effectively are "orders of magnitude" more complex, Good says.
As a result, automakers have been a little more cautious about rolling out collision avoidance systems that give significant control over the car's controls to a computer.
"Yes they are out there, but these are vehicles that are hard to get," Good says. "My guess is the companies are being a little cautious about distributing this technology."