Abstract:

Aiming at the accurate representation of road traffic flow with operational state influenced by driver fatigue, this paper proposes an improved onedimensional cellular automata traffic flow model, and further discusses the traffic flow under the model. WIt first analyzes the properties of the pilot fatigue under the periodic boundary conditions. It then defines the vehicle fatigue ratio which describes the degree of fatigue in a certain traffic flow. Two evolution rules, by fatigue vehicles and normal vehicles respectively, are used in the model to update vehicle operation states. Simulations reveal the underlying relationships between each pair of the speed, the flow density and the flow quantity under various fatigue ratios. Further analysis on safety of traffic flow including fatigue vehicles is also proposed in this paper. The simulation results show that along with the fatigue ration increasing, (a) the places traffic congestions happened trend to scatter in space, (b) congestion frequency increase significantly, and (c) the flow safety declines. Experimental results prove the superior of the proposed model in an accurate representation of the traffic flow over the SDNaSch model.

Key words: systems engineering, driver fatigue, cellular automata, traffic safety, computer simulation

摘要：

为了研究驾驶疲劳对道路交通流运行状态的影响，提出了一种改进的一维元胞自动机交通流模型.在周期性边界条件下，通过分析驾驶员的疲劳特性，考虑驾驶疲劳对驾驶员驾驶行为的影响，分别对疲劳车辆与正常车辆制定各自的演化规则，并以此对车辆进行状态更新，以建立改进的交通流模型.通过计算机仿真实验，得出不同疲劳车辆比例下车流密度、速度与流量的关系数据，并分析了疲劳车辆对交通流安全性的影响.仿真结果表明，对于本文改进的模型，随着道路上疲劳车辆比例的增加，交通流的拥堵呈分散趋势，车辆的拥堵频率显著提高，整体车流的安全性有所下降.同传统的SDNaSch模型相比，能够更好地描述道路交通流的实际运行状态.

关键词: 系统工程, 驾驶疲劳, 元胞自动机, 交通安全, 计算机模拟