International Journal of Engineering and Technology

Collision warning and collision avoidance systems are emerging automotive safety technologies that assist drivers in avoiding rear-end collisions. Their function is to allow the driver enough time to avoid the crash and yet avoid annoying the driver with alerts perceived as occurring too early or unnecessary. The purpose of this paper is to review various mechanisms under development or developed rear end collision avoidance of automobiles. Some of the reviewed work include an automatic braking system that safely stops an automobile while approaching an obstruction to avoid collision. Another separate but related system is to have a detection device, which alerts the driver in case the automobile veers off the road by crossing either the centre or side painted lines. The braking system senses an obstacle, calculates the relative distance and applies the variable brakes automatically to maintain a safe distance. Warning devices and sensor mechanisms used in obstacle avoidance systems are also reviewed.