Legal limits
What adaptive cruise control (ACC) can do:
- Maintain safe distance from the car ahead, regardless of its speed
- Halt the car in city traffic, restart at driver command
- Alert the driver to hazards
- Apply gentle braking if the driver still does not respond
- Mitigate severity of unavoidable collisions by braking moderately
What ACC could do if laws allowed:
- Apply full emergency braking to avoid an accident
- Inhibit re-start in city traffic if a pedestrian is in front of the vehicle
- Intervene in steering to avoid an obstacle
- Adapt vehicle's speed to suit local conditions
Barriers to adoption
- High cost, especially sensing systems
- Packaging cameras or radar in vehicle
- Lack of user familiarity
- Legal ambiguity on automated emergency braking
Automakers and suppliers are developing increasingly capable adaptive cruise control systems, but high costs and an uncertain legal climate are slowing sales.