Study On Lane Changing Models For Traffic Micro-simulation

With the rapid development of economy in China, vehicle volume is increasing heavily. Therefore, the consequent traffic problems of traffic congestion, traffic accidents and environment pollution become a headache of city managers. These cause direct economic losses due to delays and accident, and indirect economic losses due to environmental impact. In most cases, the capacity of the existing roadway systems cannot be increased by adding additional lanes due to space, resource, or environmental constraints. Potential ways to address the congestion problem are to improve the utilization of the existing systems through better traffic management and operations strategies, and improve the geometric design of roads and highways.Traffic operations in the congested sections of roadways is very complex, since different drivers employ different techniques to travel through such sections while interacting with other drivers. To understand the occurrence of bottlenecks and to devise solutions for it, a comprehensive analysis of vehicle to vehicle interactions is essential. This requires the development of traffic theories to explain driver behavior at the microscopic level. Besides, traffic system is complex and nonlinear, traffic simulation is becoming an efficient way.In traffic microscopic simulation, the main elements are the acceleration and lane changing dimensions. During the last years, most study has focused on car-following model (acceleration model), while lane changing has received few attention. Since lane changing maneuvers often act as initial perturbations, it is crucial to understand their impact on the capacity, stability, and breakdown of traffic flows. Particularly near bottleneck sections such as on-ramps and off-ramps, lane changing is often a significant ingredient to trigger a traffic breakdown. Additionally, the drivers' lane-changing behavior has direct influence on traffic safety. So, the quality of lane changing affects the simulation directly. The research is about the study of the lane changing, the framework for the structure of lane changing be proposed and the process of changing lane is modeled.The research is composed of interrelated chapters as follows:At first it is introduced the concept and sorts of traffic advantage and disadvantage. Then Research methods and achievements undertaken by overseas and domestic researchers are summed up. In light of above work, the research contents, significance of the dissertation are raised.In second part of the dissertation, a literature review of the existing acceleration and lane changing models is presented. Lane changes are classified as either mandatory or discretionary. After analyzing the disadvantages of the exiting lane changing models, research route of the dissertation is raisedIn the third part of the dissertation, it introduced the ways of data collection in traffic engineer and the ways in microscopic traffic data collection. Under the analyzing of the usability and applicability of various ways, it presents the way that videorecords the vehicles steering in the road, then through Image processing, the data of vehicles'position, velocity can be gained.The forth part of the dissertation, it enumerates some reasons that may cause lane changing. A lane change decision process is assumed to have the following three steps: decision to consider a lane changing, choice of a target lane, and acceptance of a gap in the target lane then actualize the lane changing. Then it presents data, collected from video-recording, on the microscopic details of lane changing on the urban roads. Through Image processing, we got the data of vehicles'position, velocity. Under the analyzing of the data, lane changing is classified three classes: free lane change,"cooperative"lane change and forced lane change. Then ,changing lane is modeled, and the frame be gave that calculate the acceleration during the lane changing.In the end, the research works are summarized. The findings and achievements analyzed, and the innovation concluded. Finally, future research works are brought forward.