Optimising UAV Data Acquisition and Processing for Photogrammetry: A Review

Abstract

Unmanned aerial vehicles (UAVs) are used to acquire measurement data for an increasing number of applications. Photogrammetric studies based on UAV data, thanks to the significant development of computer vision techniques, photogrammetry, and equipment miniaturization, allow sufficient accuracy for many engineering and non-engineering applications to be achieved. In addition to accuracy, development time and cost of data acquisition and processing are also important issues. The aim of this paper is to present potential limitations in the use of UAVs to acquire measurement data and to present measurement and processing techniques affecting the optimisation of work both in terms of accuracy and economy. Issues related to the type of drones used (multi-rotor, fixed-wing), type of shutter in the camera (rolling shutter, global shutter ), camera calibration method (pre-calibration, self-calibration), georeferencing method (direct, indirect), technique of measuring the external images orientation parameters (RTK, PPK, PPP), flight design methods and the type of software used were analysed.

Drones and Real-Time Kinematic Base Station Integration for Documenting Inaccessible Ruins: A Case Study Approach

“…However, there is also the possibility of directly georeferencing the drone images using GNSS stations connected to the UAV system, which then exploits RTK or PPK technologies. In this way, the direct georeferencing of the data can be realised [12,13,33,34], i.e., reducing the need to acquire several GCPs on the ground.…”

PPK Processing to Boost Uas Accuracy in Cadastral Mapping

“…This has been achieved by replacing topographic campaigns with high-quality Global Navigation Satellite System (GNSS) receivers mounted directly on the UAS platforms (Cucci et al, 2017;Ioli et al, 2021), integrating angular attitude measurements from accelerometers and gyroscopes (Stöcker et al, 2017), or employing other sensor fusion techniques (Negru et al, 2023). It is important to note that an efficient synchronisation between different sensors is essential due to the high speed of the UAS during surveys (Ekaso et al, 2020;Pargieła, 2023). Few studies have aimed to eliminate the need for GCPs in ground-based surveys, particularly for applications where UAS usage is not feasible due to regulatory restrictions, safety concerns, or security issues (Forlani et al, 2014;Morelli et al, 2022;.…”