String Stability and Platoon Safety Analysis of a New Car-Following Model Considering a Stabilization Strategy

Abstract

Adaptive cruise control (ACC) systems can reduce collision risk and make traffic flow more smoothly; nevertheless, improving the string stability and car-following safety in ACC systems has remained an important research topic. Based on the desired safety margin (DSM) model adopted as an ACC velocity control method, a sliding mode controller is proposed to investigate string stability and car-following safety using the time headway policy (THP), and its stability is verified by the Lyapunov stability theory. Furthermore, numerical simulations are conducted to verify the effectiveness of the proposed stabilization strategy for the stability of the DSM model. Analyzing the risk assessment indexes (time-to-collision, TTC, and time headway, TH) of the DSM model reveals that the proposed stabilization strategy can improve the traffic flow stability and avoid rear-end collision risks when the leading car exhibits a small disturbance. Therefore, the proposed stabilization strategy is valuable for designing ACC controllers to enhance traffic flow stability and car-following safety in automotive platoon driving.

Keywords

• String stability
• safety margin
• adaptive cruise control system
• stabilization strategy
• time headway policy