基于元胞自动机的环形交叉口通行能力分析

为了描述环形交叉口交织区交通流运行态势的复杂性和不稳定性,采用微观元胞自动机模型模拟交织区的车流运行规律.首先基于环形交叉口圆环形结构和车流流向,建立六边形元胞空间替代传统矩形元胞空间以及定义多值元胞状态,进而提出基于改进间隙接受理论的元胞规则分析交叉口交织区通行能力,最后利用Matlab编程进行数值模拟仿真.仿真结果表明:所建立的六边形元胞空间能够有效地模拟交织区交通流运行;改进的元胞规则能够准确地描述交织区的通行能力波动性和变化曲线,为环形交叉口信号控制和协调优化提供基本依据.

Analysis of Roundabout Capacity Based on Cellular Automata

To describe complexity and instability of traffic flow operation in weaving area of roundabout, a microscopic cellular automata model was applied to simulate traffic laws. Firstly, based on the roundabout ' s circular structure and directions of flow, a hexagonal cellular space with multi-value cellular state instead of traditional rectangle was built. Then the cellular rule based on improved gap-acceptance theory was proposed to analyze the capacity of weaving areas. Finally, the numerical simulation was made by using MATLAB software. The simulation results show that the environment of hexagonal space can simulate the operation of traffic stream in weaving areas, in addition, the improved cellular rules can accurately describe the change curve and volatility of traffic capacity in weaving areas. The research results provide a fundamental basis for signal control and coordinative optimization in roundabouts.