Research In Lane-based Road Network Model And Microscopic Transportation Simulation

In recent years, with the continuous expansion of cities and transportation development, much more attention has been put on the clearness of transportation network and service facing to the purpose of increasing convenience for transportation. Correspondingly, a series of problems afterwards, such as traffic jam, tail gas, have negatively affected the quality of people's life. It has become a significant method using transportation simulation, realized by computer software, to analyze the development of cities and transportation circulation.Microscopic transportation simulation considers single vehicle as the object in analysis by simulating the characteristics of transportation behaviors. With the increase of computers' capability in simulation, the research will never be limited by the power of computers and has expanded from small part to complete road network. Thus, effective model for transportation network is increasingly needed in applying such simulation into larger network. Based on the features of Micro-simulation, correspondent model should take lanes as the smallest unit, include multi-level network elements, as well as accurately expressing traits of topological structure in each level. However, current models still needs some improvements in this aspect. Combining with current GIS-T data model, this thesis develops a transportation network model facing to Micro-simulation of transportation, on the basis of existing model. This new model holds the traits of various transportation levels, including such five elements as road centerline, carriageway, lane, road node, and road intersection. Every part embraces spatial geometrical characteristics and attributes. Lanes are the smallest unit in this model and topological relationship exists among lanes. In addition, this essay analyzes the main vehicle models in micro-simulation of transportation, as well as car-following model and lane-changing model. This essay also compares the current model with this new model, which uses IDM and MOBIL in developing a micro-simulation system, based on C# language and Visual Studio platform. This new system has satisfactory visual expression effect, and is provided with a certain of flexibility and compatibility. It could also be adjusted based on different road data, generating the transportation network with different scales. In the process of simulation, it could set the parameters in car following model, and lane-change model, keeping the different traits of different vehicles. Such information could be reached as current speed, highest speed, travel time, waiting time. More characteristics, such as volume of flow, average speed and passing period could be acquired after calculation. Besides, the outcome from this simulation can be further combined with other data, serving the information about tail gas and energy consumption. This process supports the analysis in cities and transportation development, and assist with later policy making and development plan by providing with data analysis and decision support.