INVESTIGATION OF ACCURACY CHARACTERISTICS OF NAVIGATION SYSTEMS USING REMOTE SENSING DATA

Abstract

The article considers methods of the navigation for Unmanned Aerial Vehicles (UAV) based on the Earth remote probe data, i.e. high resolution aerial or space photographs which are specially processed. For video navigation, there are used orthonormal photographs of areal; for micros relief navigation, there are processed photographs by stereophotogrammetry method. The methods of video navigation are based on the separation and comparison of characteristic points in the current and reference images. Depending on the available reference data as the photographs, the video navigation divides between the connections of terrain to the images and the odometry. The odometer navigation does need reference data which is its positive feature, but the principles of odometer navigation enclosure in an increase of errors along measurements of the navigation parameters. The video navigation with the connections of terrain to the images provides more accurate characteristics, but it requires a preliminary preparation of reference data and uses an on-board computer with a large memory capacity. The created methods of video navigation are examined by the mathematic modelling. The results demonstrated that it is advantageous to combine both methods. In this case, the expected accuracy of the UAV navigation using the introduced methods is comparable to accuracy of a satellite navigation system. The realization of video navigation methods in an onboars computer based on NVIDIA Jetson TX2 single-board module demonstrated its efficiency in real time. The methods of the navigation by micro relief are based on a search estimation of UAV coordinates within the limits of the confidential square. The results of mathematics modelling of the micro relief navigation demonstrated that this method is serviceable with a high accuracy (3 to 8 m) both in the UAV flights over a man-made environment and in the UAV flights over a natural objects composition. The realization of navigation by the micro relief in an on-board computer build with Salut-EL24PM2 RAYaZh.441461.031 module demonstrated its serviceability in real time. The introduced methods of video navigation and navigation by micro relied were successfully approved with a semi-natural modelling. In near time, the flight tests will be intended. For practical realization of the created methods for the highprecision navigation, it is required to resolve this question providing the user with referent data which should obtain the operative processing for actual space-and-aerial photographs with the high resolution against the area.