Study on the realization and optimization of optimal path analysis

Recent implementation of the best path capability based on road network data

Requirements: Query the best path between two points, including the shortest time, shortest distance, bypass high-speed (these three based on traffic), as well as obstacle avoidance. And the implementation of the car and the people of the applicable program.

Data storage: Network data is stored in the PostGIS database

Data processing:

1, the existing road network cable data for the establishment of a topological relationship, this can be established on some commercial platforms, such as ArcMap and Supermap desktop can be.

2, the data into the PostGIS library, the length of the storage line, the average speed of travel, whether the car, whether the person row, road level, road name and other fields to perfect.

3, establish the index field, the upper and lower travel number fields and spatial fields are indexed.

Algorithm implementation: This method uses the mature Dijkstra algorithm and the Astar algorithm.

1, first to the road network information query, the establishment of network relationship data, the general method is to meet the driving conditions of the data are all obtained.

Optimization method: A After the beginning and end of the data to extend the scope of the query:

Make small-scale queries that throw out data that is not used by the data.

b on the road network to establish a data level, if the starting point is more than 10 kilometers straight line, the higher level (high-speed) on the road online query, in order to ensure the reduction of data volume, to find the most recent high-speed exit from the start and end of the analysis, and then the starting point and the corresponding access port according to a optimization method

2. Get the optimal node of the nearest boundary. such as boundaries have NodeA and NodeB need to derive the optimal node node.

3, the use of mature Dijkstra algorithm and Astar algorithm for analysis. Get the best path based on different weights.

4. After obtaining the path, the starting point and the obtained path are processed, connecting the beginning and end point of its path, connecting the endpoint with the end of the path.

5, the navigation information to extract, according to the road name of the different direction of driving tips, and navigation records associated road information.

Final result

Study on the realization and optimization of optimal path analysis