On the Accuracy and Application of UAV-Based Coastal Monitoring

Abstract

Abstract With the development of unmanned aerial vehicle (UAV) technology, its application in scientific fields, such as coastal monitoring, has become increasingly prevalent. The utilization of multi-sensor UAV platforms has made unmanned and highly repetitive monitoring feasible. This study employs three commercially available UAV systems with representative characteristics to generate Digital Surface Models (DSM) in the Lingang Tidal Flat (Shanghai), and evaluate the DSMs produced by each UAV comparing with the in-situ measurements. According to the results, the beach DSM produced by the non-RTK UAV using the Structure From Motion (SFM) algorithm is likely to be unusable. In contrast, the RTK-equipped UAV achieved an elevation accuracy of 0.3–0.54 m. The addition of a laser radar (Lidar) module further improved the accuracy to 0.1 m, significantly enhancing its reliability for comparison. We also explored a method for reconstructing the beach DEM by detecting waterlines from UAV imagery. Furthermore, during the discussion, the accurate DSM was utilized to explore the potential application of UAV technology in coastal management visualization. By adopting the digital twin framework, it would be possible and efficient to create a realistic representation of the coast, integrating actual ocean data such as tidal levels. This approach could enable the identification of coastal risks with relative ease.