These point clouds were derived from low-altitude (approximately 92-m above ground surface) images collected from unmannned aerial system (UAS) flights over an edge-of-field, paired sampling site that is part of U.S. Geological Survey (USGS) Great Lakes Restoration Initiative (GLRI) monitoring. The objective of this UAS photogrammetry data collection was to provide information on the tile-drain network in each of the two fields with the goal of understanding already observed patterns in runoff amount and water quality from these sites. A 3DR Solo quadcopter served as the flight vehicle, controlled in pre-planned missions using Mission Planner. UAS and the multispectral camera (MicaSense RedEdge) both recorded geospatial information in WGS84; the point clouds are also in WGS84 although final images are in NAD83 UTM Zone 16N. This multispectral camera provides independent images for five wavelength ranges: blue (B; approximately 475-500 nanometers [nm]), green (G; 550-560 nm), red (R: 660-670 nm), red-edge (710-720 nm), and near infrared (NR; 820-860 nm), that are co-located and processed together (MicaSense, 2015); images are provided as R-G-B and as NR-B-G. Thermal-infrared (ThIR) data were collected using a FLIR Vue Pro R 640 thermal camera with an uncooled vanadium oxide microbolometer and a 13-mm lens. Multispectral images were collected at 2-second intervals, with a flight speed of 7 meters per second (m/s) and 75% overlap; these images were georeferenced. Thermal images were collected with a flight speed of 5 m/s and 65% overlap (55% sidelap) and geo-referenced after collection by integrating the flight logs and photo timestamps using GeoSetter (3.4 BETA). Ground control was evaluated using the location of two surface flumes in addition to "ground rulers" that were visible in multispectral images; absolute error ranged from 5.36 to 12.92 m among the four photo-sets, with relative error of -0.06 to 0.06 m for the ground rulers. USGS monitoring sites include Bull Rapids Road near Harlan, IN (USGS Site IDs 411229084541101, 411229084541102, 411228084541701, 411228084541702, and 411228084541703).
Citation: MicaSense, Inc. (2015). MicaSense RedEdge. MicaSense, Inc. Seattle, WA, micasense.com.