Urban Traffic Platoon Dispersion Study in Beijing

Many Chinese cities have imported Urban Traffic Control Systems (UTCS) from Western countries. However, these systems, neither the fixed-time control system nor the real-time adaptive control system worked well under the unique traffic situation in Chinese cities. Their software and hardware was not intended to develop compatible with China's traffic flow Characteristics. A very common parameter, the platoon dispersion factor, which mainly affects the quality of the traffic control system, is determined by law of geometric distribution or normal distribution, and mostly is defined as a constant. Whether the motion law of traffic flow between two junctions in China is the same with the law abroad, is still a question. In this article, we attempt to explore the urban traffic platoon's dispersion parameters and the relevant factors related through on-site survey in Beijing. And by traffic simulations, we make a comparative analysis between the laws of traffic flow abroad and in Beijing. The traffic dispersion factor compatible to Beijing's situation was presented and some suggestions on China's urban traffic control system development were also addressed.