Research On Creating And Storing Indoor Map Base On Magnetic Field

The LBS(location-based service)outdoor has already developed maturity and also applied to our daily life.But,with the growth of the building's scale and indoor's complexity,the LBS indoor become more and more important,and has encouraged the development of the mapping and location indoor.There are a variety of solutions for mapping and providing the location service indoor have proposed,but no one can be widely applied to our daily life so far.The growing popularity of smartphones and the coming of Internet of Things(IoT)make it possible to implement indoor location at a large scale.Therefore,the purpose of this paper is to propose and design a method that can create the indoor map efficiently and conveniently,and propose solutions that support massive unstructured data.The main contents of this paper include mapping indoor and designing map server.The method of mapping indoor is using geomagnetic sensor of the smart phone to collect the geomagnetic field distribution map of the indoor corridor firstly,and make it as the fingerprint information of the positioning system;then,using the accelerometer value acquired by the acceleration sensor,combining the step detection model and the estimation algorithm for dynamic step-size,to estimate distance indoor corridor.Finally,defined a graph structure indoor map with the key elements of the indoor space environment and their relationship.In designing map server,firstly,we choose MongoDB that is a non-relational database with rich features as the data storage database,and use replica set and shard function of MongoDB to design a distributed storage system which is high availability and scalability for unstructured and massive indoor map.Then,the Flask framework is used to develop the indoor map application program to realize the application interface design of MongDB distributed database and the related service processing for indoor map.Finally,we build a high-performance web server based on Nginx,uWSGI to accept the requests from a client.The results of experiment prove that the method of creating the indoor map based on geomagnetic fields is efficient,economical and convenient.The indoor map can be well applied to indoor positioning and navigation through this method.At the same time,the distributed indoor map storage system designed in this paper has high reliability and expansibility,and can provide the map data warehouse for indoor positioning technology based on geomagnetism and indoor location service.