Interior Buildings Localization And Navigation Based On Complex Background Magnetic Fields

Interior buildings localization and navigation based on complicated ambient magnetic fields has important theoretical and practical significance. For the earth’s magnetic field is the natural resources of the earth, and it is a vector field that exists around the earth, so as a passive autonomous navigation method, it does not need to receive information from the outside world, and does not depend on the in building infrastructure, error does not accumulate with time and other characteristics. Such as the occurrence of fire or power system outage etc., the navigation results are not affected, which shows the unique advantages of geomagnetic navigation. However, in the space of the building, due to its complex magnetic environment, the research on the location and navigation of geomagnetic field in the building is less.This paper first analyses the building effect of geomagnetic distribution of various factors, and model the description. Because there is a lot of ferromagnetic material in the building, the geomagnetic distribution is very complex, In this paper, the ferromagnetic material classification, and study the effect of each type of ferromagnetic objects. Due to the residual magnetization of ferromagnetic material itself and the characteristics of the magnetic field intensity which is magnetized by the external magnetic field, the effects of the magnetic field intensity on the magnetic field distribution are characterized by the model of permanent magnet and ferromagnetic particle.Secondly, we put forward a multi parameter localization algorithm based on the geomagnetic field, geomagnetic parameters of the magnetic field strength combined with acceleration parameter localization, the algorithm in the magnetic field strength parameter segment as a unit, can reduce the accidental error of single point positioning algorithm. Aiming at the shortcomings of the buildings within the heading angle measurement prone to bias, the algorithm with positioning accuracy does not depend on the characteristics of the heading angle measurement accuracy.Finally, in view of the geomagnetic navigation at the beginning of the general need for calibration, and not convenient to use, so a method is put forward, makes magnetic factors do not affect the positioning results. Through processing geomagnetic data which includes magnetic effect, no calibration is also able to maintain the positioning accuracy.Through the study of the above three aspects, an experimental system was established, and experiments are carried out in 3 different buildings, and the results show that the model and algorithm are feasible and effective.