Research Of Path Planning Model Based On Hotspots Evaluation

With the rapid growth of person flow and traffic flow,traffic problems have become increasingly serious.Even traffic accidents become a worldwide public hazard.The advent and development of intelligent transportation system helps cut down the traffic accident rate and ease the traffic congestion and pollution effectively.Navigation System,which can provide more convenience for the traffic,is an important subject in Intelligent Transportation.Path planning,as a core component of the Navigation System,has always been a research hotspot.How to quickly plan the shortest path to the destination is the basic function of the Navigation System.However,in a real environment,the shortest path may have potential serious dangers,causing more risk and more additional travel time.In other words,the shortest path is not necessarily the optimal path.To solve this problem,a heuristic path-planning algorithm is improved.This algorithm can provide an optimal path by searching for road section,which be acquired by segment division method based on road characteristics and background properties.In this paper,real-time traffic conditions and historical traffic data are considered as road impedance factors.Based on the research outcome of the thesis,alleviated traffic jams and improved road traffic safety will provide drivers’trip more advantages.The main contents are as follows:First,concept of accident hotspots and the method of accident hotspots identification are introduced.Based on analysis accident hotspots’cause,a new segment division method based on road characteristics and background properties is proposed to judge traffic characteristics and safety more exactly.Second,according to the characteristic of time series of traffic congestion,a evaluate method of the traffic status based on the division of the time period is proposed.A new evaluation function for assessing the traffic danger degree is proposed based on fitting analysis of real-time traffic status and accident hotspots’distribution.The evaluation mechanism of the link impedance is constructed,where traffic status and traffic danger degree are regard as factor.At last,the evaluation function of A* algorithm is improved in various ways,such as distance to the end,search direct and proportion of the evaluation function.Experiment results prove the validity and efficiency of improvedA* algorithm.