BMW is in the testing phases with its Left Turn Assistant, which aims to reduce left-turn crashes.
The sensor, being tested on the BMW 5 Series test vehicle, detects cars, trucks and motorcycles in nearby traffic lanes. Before a vehicle takes a left turn with the assistant activated, three laser scanners in the front of the car scan the area where the car will be moving and up to 100 meters in front of the car. If the car is traveling 10km/h (about 6.2 mph) or slower and another vehicle is detected in the area, the car will automatically brake, a warning tone will sound, warning symbols will display on the instrument cluster and a Head-Up Display will explain the reason for the stop.
“This automated action is triggered deliberately without a prior warning stage, as a rapid response is vital in this situation to prevent the car from moving into the intersection and presenting an obstacle to oncoming traffic,” according to a BMW press release. “If the driver first had to react to a warning, the car would continue forward into the collision area and an accident would no longer be avoidable.”
Drivers can continue moving once the brake is engaged. The assistant can also be disengaged if a driver needs to move over in an emergency situation.
In addition the Left Turn Assistant, a WLAN car-to-x communication unit is being tested. Vehicles that have the Left Turn Assistant can install the WLAN to increase detection to 250 meters in front of the car. Also, the system will communicate with any other vehicle with WLAN, including motorcycles. The motorcycle component is being tested on the BMW R 1200 GS.
“The car and the motorcycle communicate with one another via the car-to-x interfaces as the motorcycle approaches. The car and motorcycle exchange information on the type of vehicle, its position and speed, as well as dynamic data such as its current steering angle and whether the indicators are activated,” explained Udo Rietschel, development engineer in the BMW Group Research and Technology’s Left Turn Assistant project.
The motorcycle and car’s WLAN systems in this situation would detect whether a collision is likely using algorithms calculating trajectories. If a collision is anticipated, warning measures automatically take effect on the motorcycle and can range from the horn sounding to headlight strength being increased to lights flashing to LEDs activated to create a broader silhouette. If the vehicles still get too close, the Left Turn Assistant will be activated on the car.