Review of Car-Following Theory

Steadily increasing volumes of traffic and the accompanying concern for safety have spawned the need for a thorough understanding of the dynamic characteristics of vehicular flow. Car-following theory has been developed as a mathematical description of traffic flow on long, straight highways in dense flow conditions. This theory, consisting of a body of over 30 models, provides a conceptual basis for understanding traffic phenomena, permits analysis of safety considerations, allows a determination of highway capacity, and provides a basis for automatic control of vehicles. A primary intuitive appeal of the car following methodology is this microscopic consideration of the actual factors involved in the driving process. Milestones in the development of car following theory are traced from initial investigations to current studies. Theoretical justifications employed in the development of the better known models are related.