Application of low-altitude airspace UAVs in beach terrain monitoring

With the development of consumer-grade unmanned aerial vehicles (UAVs), new possibilities for beach monitoring are now available. However, different monitoring accuracies and suitability exist across different UAV platforms. We employed two UAV platforms, namely the DJI Phantom 4 RTK and DJI M300 RTK, in combination with two terrain monitoring techniques: Structure from Motion (SFM) photogrammetry and Light Detection and Ranging (LIDAR), to undertake beach terrain monitoring at Dasha Beach in Xiangshan County, Zhejiang, East China. The planimetric and elevation errors of low-altitude UAV measurements were assessed. Differences among the synchronously monitored results of diverse UAV platforms were analyzed, and their respective application scenarios were discussed. Additionally, we analyzed beach terrain characteristics and investigated beach terrain variations before and after winter. The analysis results show that the drone platform is capable of performing high-precision monitoring of beach topographic changes.