Aerial mapping based on arrangement of optical electron cameras

Abstract

Subject of Research. The paper proposes an approach to aerial mapping that provides the photogrammetric quality of images necessary for creating orthophotoplans with high cartographic similarity. The topicality of the approach is determined by cartographic similarity reduction of the area orthophotoplans in case of automated processing of images obtained from an unmanned aerial vehicle in disturbed flight conditions. In particular, artifacts are formed on orthophotoplans that reduce the area representation adequacy in the image and prevent the correct visual interpretation of images. We propose an approach that provides planned area images, and after their automated processing orthophotoplans of places are formed with improved cartographic similarity. Method. The aerial mapping approach is based on the idea of applying the arrangement of optical-electronic cameras that analyze navigation measurement data. The proposed approach gives the possibility to minimize image perspective geometric distortions on pitch, roll and yaw that occur when an unmanned aircraft turns around during flight. Consequently, the conditions for planned aerial photography are met and, as a result, aerial images with the required photogrammetric quality are obtained. The absence of perspective geometric distortions in the images provides the creation of the area orthophotoplan without visible distortions. Main Results. A model of an aerial image geometric distortions has been developed that analyzes the effect of the optical- electronic camera sight line deviation from the direction to nadir on the occurrence of perspective geometric image distortions. Calculation results are presented for parameters of the frame projection on the earth surface for lenses with different angular fields of view. Following on from the results, an approach to aerial mapping is proposed using an optical-electronic camera arrangement that provides planned area images in the conditions of an unmanned aerial vehicle maneuvering. Practical Relevance. The arrangement of optoelectronic cameras in aerial mapping makes it possible to get planned images without additional technical means of shooting equipment stabilization and ensures the aerodynamic quality of an unmanned aerial vehicle airframe. In addition, the application of the proposed technical solution maintains the transfer characteristics of lenses of optoelectronic cameras installed in the body of an unmanned aerial vehicle and functioning in conditions of significant changes in the ambient temperature. The results of experiments demonstrate an increase in the cartographic similarity of orthophotoplans when selecting images obtained by applying the arrangement of optoelectronic cameras for aerial photography.