【作者】 王浩；

【导师】 马寿峰；

【作者基本信息】 天津大学 ， 系统工程， 2004， 硕士

【摘要】 交通流仿真是当前城市交通仿真研究的热点,在仿真系统中,需要考虑车辆与系统,车辆与车辆,车辆与道路之间的相互作用,利用跟驰模型、超车与换道模型等微观数学模型,可以在计算机仿真上模拟出每一辆车在路网上的运行。现有的交通流模型未考虑道路的几何特性等因素,因此仿真结果与实际会有所偏差,本文从分析立交枢纽的线形入手,考虑实际驾车行为,得到了适用于弯度与坡度的交通流仿真模型,并建立了立交枢纽的计算机模型,最后设计完成了立交枢纽的交通流仿真系统。立交枢纽的线形多变,直线、圆曲线与缓和曲线为平面线形组成的三个基本要素,坡度反应纵断面的路线起伏,本文分析了立交枢纽的微观线形组成,将其分为不同的路段,每条路段具有不同的几何特性,以此建立了立交枢纽的计算机模型,并设计了计算机方法,可使车辆按照建立的计算机模型在立交枢纽上行驶,并将立交枢纽用计算机图形描绘显示。针对已有的交通流模型中,较少或没有考虑道路的几何线形,本文从车辆在有坡度与弯度的道路上行驶的受力作为出发点,分析得出在道路转弯半径不同时的安全行驶的条件,在坡道上行驶时汽车牵引力以外的加速度以及习惯性的行驶行为,并通过这些因素对跟驰模型进行了修正,从而得到了一种适用于道路具有弯度与坡度上的跟驰模型。利用仿真技术,根据仿真的目标,重点解决了出入口匝道处的仿真模块,完成了立交枢纽交通流仿真系统的设计,最后对出入口匝道进行了仿真实验,实验结果验证了本系统可以进行立交枢纽的交通流仿真,并建立立交枢纽的仿真实例,给出了仿真结果。更多还原

【Abstract】 Traffic flow simulation is the hot issue of urban traffic simulation. In the system,the impact between vehicles and system, the vehicles and vehicles, the vehicles andthe roads should be taken into account. The simulation systems utilize thecar-following model, lane-change model, and so on, and then simulate the vehiclesrunning in the road net. The traffic flow model proposed before didn’t take thegeometry of the road into account, so the result maybe not correct. This thesis firstlyanalyses the shape of the cloverleaf and considers the habits during the drivers driving,then develop the model which can be used on the road with curvature and longitudinalgradient, get the computer model of the cloverleaf, and lastly complete the traffic flowsimulation system of the cloverleaf.The shape of the cloverleaf is variable, the beeline, the round curve and theconvolute curve is the basic elements for the plane curves,the longitudinal gradientreflects the change of the vertical section. This thesis analyses the constituent parts ofthe cloverleaf, then disassembles it variable parts that have different geometryfeatures. The variable parts make up the computer model of the cloverleaf. And thisthesis designs methods that enable the vehicles moving according the establishedcloverleaf model, and displays the cloverleaf on the screen.Little or no geometry has been considered in existing traffic model,the thesistakes the vehicles’ force which move on the road with longitudinal gradient andcurvature, as beginning, analyses the safety conditions of moving when the radiusesof the road change, the acceleration except for traction and Behavior that gohabitually when the vehicles move on road with longitudinal gradient. A car-followingmodel that is suitable for road with longitudinal gradient and curvature is obtained byameliorating the factors of the car-following model.The thesis established simulation module of the entrance and exit at the ramp,finished the design of cloverleaf’s traffic simulation systems utilizing simulatedtechnology in accordance with the target. Simulation of the entrance and exit at theramp was done at last, the results show that the system in the thesis can simulate thecloverleaf’s traffic flow. The thesis also gives some simulation cases for establishingcloverleaf’s traffic flow and the results of simulation.更多还原