Research On Key Technologies Of Path Planning Based On The Hierarchical Road Network Model

In recent years,with the continuous improvement of the level of urbanization,urban population and vehicle surge has brought serious traffic jams,a higher requirement for path planning services based on electronic maps has been put forward.This paper is devoted to the study of a path planning technology based on the hierarchical road network model,the main research contents are as follows:(1)A conceptual model and its expression of the hierarchical network based on hierarchical division are proposed.The structure and characteristics of highway,urban road traffic network in China and the storage structure of the graph are studied and analyzed.For the different road division standards,different raod grades and high density and orther features,the road network is divided into several levels.(2)A topology generation algorithm based on hierarchical network is studied.The original error in the map is automatically correct and the correctness of the network topology generation is guaranteed based on the calculation method of topological relations in road network.It laid the foundation for the study of the follow-up optimal path algorithm.(3)An improved A*algorithm based on hierarchical road network is studied.The scale factor is added on the basis of the Manhattan distance as the heuristic function,the optimal value of the scale factor is determined by experiment,which effectively improves the efficiency of the algorithm.Experiments show that the algorithm has achieved good results in the hierarchical road network path planning.(4)A set of path planning system was developed based on the MapX component in geographic information software MapInfo.On the basis of the demand analysis,the whole framework of the system is built and the function of each module is realized.An interactive platform of path planning is provided,and the effectiveness of the above algorithm is verified experimentally.