BMW makes left turns safe
BMW's experimental Left Turn Assistant technology scans for oncoming traffic when a car makes a left turn.
BMW is developing new technology to make left turns safer. The German Federal Statistical Office cites left and U-turns as the leading cause of accidents on German roads.
The Left Turn Assistant uses GPS and a camera to determine if the driver is about to make a left turn. BMW says its GPS system can pinpoint the car to within a meter of its actual location, and so determine if it is in a left turn lane. A camera on the car is also set to identify left turn markings in the road.
The fact that the system does not rely on the left turn signal suggests German drivers are as bad as U.S. drivers when it comes to signalling.
Once the car figures out that the driver is about to turn left, it activates lasers to look 100 meters, about 100 yards, ahead. If the lasers detect oncoming traffic, the system will simultaneously activate a visual warning for the driver and hit the brakes.
Most safety systems of this nature first sound a warning, then brake the car if the driver does nothing, but BMW notes that in this situation, the car must be stopped immediately, before it moves into oncoming traffic.
The system only works at speeds below about 6 mph, appropriate for when a driver has stopped, and then began a left turn, or slowed down enough to safely make the turn. If the driver hits the brakes or taps the accelerator, the system deactivates.
The technology seems feasible, as laser speed sensors and cameras are already in use for lane departure and adaptive cruise control systems. But it will have to be highly customized for each country in which it is deployed, set to recognize different styles of lane markings.