基于元胞自动机模型的应急车辆行程时间  

Emergency vehicle travel time based on cellular automaton model

作　　者：赵韩涛[1] 马国胜[1] 毛宏燕[1] 

机构地区：[1]哈尔滨工业大学汽车工程学院,山东威海264209

出　　处：《长安大学学报（自然科学版）》2015年第2期132-137,144,共7页Journal of Chang’an University(Natural Science Edition)

基　　金：国家自然科学基金项目(51308165);山东省自然科学基金项目(ZR2013EEQ003);哈尔滨工业大学科研创新基金项目(HIT.NSRIF.2014134)

摘　　要：针对应急车辆通行时交通流参数难以实时获取的问题,提出以仿真手段模拟交通运行,进而探讨随机交通条件下应急车辆行程时间的计算。在分析有应急车辆的混合交通流运行特性的基础上,增加车辆类型,引入应急车辆影响区域和普通车辆让行概率2个参数,修改车辆换道与速度更新规则,建立了双车道交通流元胞自动机模型。利用MATLAB进行数值模拟,生成不同交通密度条件下的应急车辆行程时间,并与现有计算公式进行对比分析。研究结果表明：应急车辆仅干扰其所处位置的车流运行,对双车道总体流量没有影响,在密度位于0.12~0.36范围内优先通行效果较好;在密度较小（≤0.08）或较大（≥0.24）时,应急车辆行程时间随着行驶距离的增加呈现近似正比例的增加,且密度越大,增长的斜率越大。研究发现现有针对应急车辆的距离-行程时间函数适用于低密度及高密度交通条件,而在0.12~0.20密度范围内失去效用。To determine emergency vehicle travel time under random traffic conditions,this paper proposed a calculation method,in which vehicle travel was simulated to calculate its travel time in stochastic traffic conditions.Based on the analysis of travel characteristics of mixed traffic flow with emergency vehicles, MATLAB was used to conduct numerical simulation to produce emergency vehicle travel time in different traffic density and the results were compared with present calculation method,a two-lane traffic flow cellular automaton model was established with modified lane-changing rules and speed-updating rules.The simulation results indicate that emergency vehicle only interfere the traffic flow around it but has no effect on total traffic flow,and the priority for emergency vehicle travel has good effect in the density of 0.12 to 0.36.When the density is less than or equal to 0.08,or greater than or equal to 0.24,emergency vehicle travel time increases nearly in direct proportion with the increase of travel distance,and the greater the density is,the greater the growth slope becomes.The study found that the existingdistance-travel time function applys to traffic conditions with low and high density,but lose utility in range of 0.12 to 0.2.

关 键 词：交通工程 交通流 元胞自动机 应急车辆 行程时间 

分 类 号：U491[交通运输工程—交通运输规划与管理]