Abstract
Unmanned Aerial Vehicles (UAVs) are a new type of platform for high-resolution aerial photogrammetry. Despite of their growing applications there has been little assessment of their performance. This study reports the results from two field experiments designed to evaluate the accuracy of digital surface model (DSM) derived from the imagery acquired with a low-cost digital camera onboard an UAV. Concurrently the survey was carried out using RTK-GPS and Total Station. The first experiment was performed to evaluate the highest measurement precision at a parking lot at Hiroshima University. Another experiment was conducted in the reaches of the Jyoge River. Comparisons between the DSM and the survey data have pointed out that the number of Ground Control Point and the quality of photographic lens are important factors for high precision measurement and that the r.m.s. errors at altitude of 100 m are less than 2 cm, suggesting that UAV photogrammetry has high applicability to river morphological mapping.
