Search Results

Driver support systems without active vehicle interaction are convenience functions and can be viewed as a pre-stage to vehicle guidance and collision avoidance. By information to or an early warning of the driver a quicker reaction of the driver can be achieved. Today, Long Range Radar (LRR) and Lidar are used for the ACC function. With a range of up to 200m and superior signal quality, LRR is the key technology and main enabler for future predictive safety systems. Video technology has been introduced in a German Luxury class vehicle in 2005 for a system for night vision improvement. Also passive infrared sensing based thermal radiation sensors are used in other systems. Mid and short range applications are covered by various technologies based on Radar and optical sensing as well as on emerging new technologies. The highest demand regarding performance and reliability is put on active safety systems.

The assignment of vehicles detected by distance sensors to lanes relative to the own vehicle is an important and necessary task for future driver assistance systems like Adaptive Cruise Control (ACC). The collective motion of objects driving in front of the vehicle allows a prediction of the vehicle's own driving course. The method uses not only data of the host vehicle to determine its own trajectory but as well data from a distance sensor supplying distances and angles of objects ahead of the vehicle to determine the trajectories of these objects. Algorithms were developed using an off-line simulation, which was fed with recorded data obtained from a real ACC vehicle. The results show a significant improvement in the quality of the predicted driving course compared to other methods solely based on data of the host vehicle. Particularly in situations of changing curvature, e.g. the beginning of a bend, the algorithm helps to improve the overall system performance of ACC.

This paper is based on the experiences with Adaptive Cruise Control (ACC) systems at BOSCH. Necessary components (especially range sensor, curve sensors, actuators and display) are described, roughly specified, and their respective strength and weaknesses are addressed. The system overview contains the basic structure, the main control strategy and the concept for driver-ACC interaction. Afterwards the principal as well as the current technical limits of ACC systems are discussed. The consequences on traffic flow, safety and driver behavior are emphasized. As an outlook, development trends for extended functionality are given for the next generation of driver assistance systems.