Forward collision warning systems( FCW) for motor vehicles include those for general traffic, the Traffic Alert and Collision Avoidance System (TCAS), and special pedestrian collision warning systems, Pedestrian Forward Collision Warning (PCW).
Collision warning systems can detect the driving and braking behavior of vehicles ahead and warn drivers of a possible rear-end collision through visual, haptic or audible signals.
Pedestrian collision warning systems detect people over a certain height. They can warn the driver and, in an emergency, autonomously brake the vehicle to avoid a collision with the pedestrian. They work with video cameras or with ToF systems, Time of Flight (ToF), with image recognition and image processing. Detecting pedestrians is particularly technically challenging because human bodies vary in shape and size, and detection can be impaired by shrubs, hedges, or containers. It is even more difficult in low light conditions, darkness and dark clothing.
Improved and more powerful image recognition and processing systems that process captured images in a fraction of a second and communicate warning information to the driver have been instrumental in improving pedestrian detection.