Unsignalized Traffic Command System Based On Connected-vehicle Network Technology

Intersections linking the different directions,which are the important pivots in the road network.Because of the traffic flows come from different directions gather in the intersections that make it be easy to cause conflict between the traffic.The intersection is the hotspot of the traffic accident,so the intersection traffic safety issues are the common challenges facing the world,especially in the unsignalized intersection vehicle traffic flow without any control that only follow the basic road traffic safety laws.So its security level is lower than the intersection signal control.With the construction and development of the connected-vehicle network technology,the level of road traffic network transport efficiency,security and intelligent level have a great enhance.As an important part of the connected-vehicle network system cooperative vehicle-infrastructure system(CVIS)has become a hot research field of the road transportation.Based on the cooperative vehicle infrastructure system,the vehicle-to-vehicle and vehicle-to-infrastructure can realize information sharing and interaction,which has the very vital significance to improve the efficiency of the intersection traffic.In addition,the emergence of Unmanned Driving improved these problems,which not only reduce the burden of driver,but also make traffic jams easily.This article based on connected-vehicle network technology design a traffic command system with the Unmanned Driving in the unsignalized intersection to solve the traffic efficiency problem.This dissertation focuses on the Unmanned Driving in the unsignalized intersection with two lanes,it mainly analyzes the system framework of the connected-vehicle network technology in the intersection,including vehicles and infrastructures communication technology,intelligent vehicle system.At the same time,we use the GPS is the priority and DR is the assist way to position vehicles,by using the DSRC short-range wireless that the communication will be timely and accurate.The dissertation also establish the traffic conflict rulesAt the same time during analysis the strategy to design a traffic strategy under has different flow rate.According to analysis of the intersection vehicle trajectory,we set up a optimization model that acceleration and speed as variables under the low flow rate.This model uses optimal acceleration control to change the way speed to achieve without a stop by,a stop-and-go-style intersection coordinate method is used under the high flow.Through the genetic algorithm optimization model and the Matlab simulation proved that the command system has a great effect in improving the intersection,in the system it ensures traffic safety and improves the traffic efficiency.