Tree height measurement from aerial images taken by a small Unmanned Aerial Vehicle using Structure from Motion

Structure from Motion (SfM) is an advanced photogrammetry. In this study, three-dimensional data is taken by a small Unmanned Aerial Vehicle (UAV). Our study area is Uryu experimental forest of Hokkaido University. In this study, aerial images by a small UAV using SfM are used and applied to provide three-dimensional data of the forest. Tree height measurement from the UAV was compared with field measurement under the different condition of tree species, seasonal change, and terrain slope. The results suggest that seasonal change could largely affect the accuracy of the tree height measurement using a UAV.