Analytical And Applied Research On Cellular Automata Traffic Flow Model

Cellular automata(CA) has become one of the most important tool for traffic flow modeling. This paper will do both theoretical and practical research on the one-dimensional CA traffic flow model.Theoretical research of CA traffic flow model is relativly less than practical research. In this paper, we take theoretical research of CA traffic flow model as the major content, and following results are obtained:(1). Cellular automata model is benefit for its "rule-based and bottom-up" characteristics, but this also make analytical analysis very difficult. This paper explores the analytical result of the deterministic open-boundary NS model. The mechanism of macroscopic phenomena is explained through the microscopic rules. These reults implies that all the important statistical parameters of deterministic NS model with standard open boundaries, including inflow, capacity, density profiles and global density, are all analyzable. Furthermore, we present a aimple method for the analytical results of the expanded left boundary. And we also discuss the analytical results of the traffic-light coundary in a more theoretical way.(2).The relationship and differences between the CA models and car-following model is an important issue in the field of traffic modeling. In this paper, the similarities as well as the differences of the Optimal Velocity Model(OV model) and Nagel-Schreckenberg Model (NS model) is investigated by both analytical and numerical approaches. By analyzing the rules of both models, we prove that the NS model is a discrete form model of OV model. By numerical simulations, OV model with different parameters and stochastic NS model are compared from two aspects, including fundamental diagram and phase transiton.This article also includes several practical studies:(1) The dynamic characristics is as important as the static characristics for any dynamic system. We construct a road using the VDR model, and take the inflow as the system input, the global density as the system output. Then we explore the dynamic and static characristics of the road under step input using numerical simulation. We found that the response of the system is rapid in the free-flow phase, and the dynamic charactristics is interestion with its overshooting and periadic vibration in the jamming phase. Such research is rarely found in previous studies. (2) Mixed flow with non-motorized vehicle and motor vehicle is often found in domestic road. In this paper, we present a new model for such mixed traffic flow. Different CA models are used to model the motor-vehicles and bicycles respectively, and the bicycles impact the motor-vehicles by block and friction interferences. The characteristics of the model, including the effects of the two different interferences, the bulk dynamics and the fundamental diagram of the motor-vehicle flow under such influences are studied and discussed by numerical simulations. The performance of the model is also verified with empirical data.