Road Travel Time Estimation And Path Optimization Based On Low-Frequency Floating Car Data

Road travel time estimation and travel route optimization are important components of intelligent transportation.Traditional traffic information collection technology has many disadvantages such as high cost and difficulty in maintenance.With the rapid development of intelligent transportation technology,floating car technology has become an important means to obtain traffic flow data.It has the advantages of wide data coverage,simplicity and convenience.The commonly used floating car system is low-frequency sampling data,and there are few data samples and low accuracy.The paper proposes a road travel time estimation together with a route optimization technology based on low-frequency floating car data.This paper based on scientific research project financed by shaanxi province transportation hall "based on the existing traffic information platform of xi'an traffic congestion mitigation application research".Firstly,it studies the road travel time estimation algorithm based on lowfrequency floating car data.This algorithm mainly consists of two parts: single vehicle road travel time estimation,multi vehicle road travel time estimation fusion.In the process of estimating the travel time of single vehicle.a location-time interpolation method based on distance weights is proposed to calculate the travel time of single vehicle.At the same time,the rebuilding method and storage strategy of the missing road are given in view of the missing road in the course of vehicle driving.It ensures accurate estimation of missing road travel time and improves the execution efficiency of the algorithm.After obtaining all the road travel time data of single vehicle,the multi-vehicle fusion road travel time estimation algorithm based on the frequency weight is used to reduce the error caused by the random factors of single vehicle on the road travel time estimation.Secondly,the shortest path optimization technique was studied.In order to meet the needs of different users,the paper proposes the corresponding shortest path optimization algorithm.(1)A direction-based heuristic backtracking algorithm is proposed for the shortest travel distance requirement.The algorithm can quickly achieve the shortest travel distance path optimization without constructing matrix road network data.(2)For the shortest travel time,this paper proposes a dynamic shortest travel time path optimization algorithm based on the combination of historical data preprocessing and road important node markings.This algorithm can provide the starting and ending points according to the real-time driving speed of the current road in a short time.The shortest travel time route.Finally,this paper proposes a detailed design and implementation of the road travel time estimation and path optimization visualization system based on low-frequency floating car data,including the detailed design of the database and the detailed design of the functional module interface,the design of the program structure,and the testing of system functions.The results show that the road travel time estimation algorithm proposed in this paper can accurately estimate the actual travel time of the road.and the path optimization algorithm can quickly give the shortest path optimization results.The visualization system realized in the research process of the thesis also basically meets the requirements of real-time processing,and can provide a good service system for the traveler and the transportation department.