基于安全驾驶的元胞自动机交通流模型

针对Nagel-Schreckenberg模型(NaSch模型)中存在的高速车辆可能发生追尾事故的不安全性，考虑了前车速度为零的情况，提出一种新的强调驾驶安全性的一维元胞自动机交通流模型：安全驾驶模型，并对该模型进行了数值模拟.由于安全概率的引入，使得系统在临界密度附近出现低速的同步相，而不是完全的堵塞相，减小了追尾事故发生的可能性，提高了高密度时道路的通行能力.模拟结果显示出了亚稳态、非平衡相变以及滞后效应等实际交通所具有的特性. 关键词： 交通流 安全驾驶 元胞自动机 同步流

Cellular automaton model of traffic flow based on safety driving

Considering the condition of having a stationary vehicle ahead, a new one-dimensional cellular automaton model emphasizing high safety is proposed to reduce the probability of rear-end collision in the Nagel-Schreckenberg model. The simulation results reveal the presence of metastable state, nonequilibrium phase transition and hysteresis effects, which have been observed in real traffic. Due to the introduction of the safety probability, traffic flow near the critical density will turn to a synchronized flow at low speed, rather than the jam state. So the probability of rear-end collision will be reduced and the traffic capacity may be increased at high traffic density.