Research on Safe Following Distance on an Expressway Based on Braking Process Analysis

As an important part of the vehicle active collision avoidance system, improvement of the minimum safe following distance model has aroused the interest of researchers at home and abroad. According to the characteristics of the safe driving of vehicles on expressways, the braking process of vehicles is analyzed using the principle of kinematics. According to the requirements of the safe following distance between vehicles, the safe following distance of different braking system structures, different following states, different speeds and different slope sections on expressways is quantitatively analyzed. Three different safe following distance calculation methods based on braking deceleration under different slope conditions are established. Matlab software was used for simulation analysis. The simulation results show that the calculation method of the safe following distance meets the requirements of keeping safe distance in the Implementation Regulations of Road Traffic Safety Law of the People’s Republic of China and provides a more specific reference basis for speed limit used on expressways. This study provides a theoretical basis for the application and interpretation of the parking sight distance value stipulated in the Design Specification for Highway Alignment, and has certain practical guiding significance for improving the density and transportation efficiency of expressway vehicles and reducing the incidence of rear-end traffic accidents.