Accuracy of UAV based data collection (case studies)

Abstract

Nowadays many new data acquisition technologies have been appeared. Due to the increasingly advanced digital devices, high resolution cameras and utility of fast processing, Unmanned Aerial Vehicles (UAV) have become a prominent feature of the various remote sensing procedures. In the past, UAVs were only available for military purposes but over the last decade the ‘drone’ equipment has become easily accessible to everybody. While in the past photogrammetry was only used by qualified professionals, it is now applied successfully in many fields. Even though UAVs are widespread in surveying practice too, the related accuracy issues are not determined regularly. The manufacturing companies may calibrate the instruments of the device one by one, e.g. camera, GNSS receiver, in which way the nominal precision of an UAV, as an integrated system can be derived considering the error propagation law. However, in the practice the actual precision may notably differ from the nominal one, caused by different internal and external effects, such the flying stability of the device (platform), weather conditions, features of the observation object, etc. Because the benefits of the technology may justify the use of data in topographic mapping, cadastral mapping or even engineering geodesy, we have conducted studies to determine the accuracy that can be achieved using UAV as an integrated data acquisition tool. First, we developed a test field in rural area for investigations. The results of the test flights conducted there were determined that what conditions influence the accuracy of the survey. In addition, cadastral measurements were performed in the populated area using UAV and GNSS technologies and the results were compared with digital cadastral map data. Investigating the feasibility of engineering geodetic applications, we have performed an artificial surface survey using UAV technology. The results and conclusions of these studies are presented in this article.

Nowadays many new data acquisition technologies have been appeared. Due to the increasingly advanced digital devices, high resolution cameras and utility of fast processing, Unmanned Aerial Vehicles (UAV) have become a prominent feature of the various remote sensing procedures. In the past, UAVs were only available for military purposes but over the last decade the ‘drone’ equipment has become easily accessible to everybody. While in the past photogrammetry was only used by qualified professionals, it is now applied successfully in many fields. Even though UAVs are widespread in surveying practice too, the related accuracy issues are not determined regularly. The manufacturing companies may calibrate the instruments of the device one by one, e.g. camera, GNSS receiver, in which way the nominal precision of an UAV, as an integrated system can be derived considering the error propagation law. However, in the practice the actual precision may notably differ from the nominal one, caused by different internal and external effects, such the flying stability of the device (platform), weather conditions, features of the observation object, etc. Because the benefits of the technology may justify the use of data in topographic mapping, cadastral mapping or even engineering geodesy, we have conducted studies to determine the accuracy that can be achieved using UAV as an integrated data acquisition tool. First, we developed a test field in rural area for investigations. The results of the test flights conducted there were determined that what conditions influence the accuracy of the survey. In addition, cadastral measurements were performed in the populated area using UAV and GNSS technologies and the results were compared with digital cadastral map data. Investigating the feasibility of engineering geodetic applications, we have performed an artificial surface survey using UAV technology. The results and conclusions of these studies are presented in this article.