Data format: Raster Dataset - GRID
File or table name: e724_sm
Coordinate system: Universal Transverse Mercator
Theme keywords: elevation, environment, geoscientific information
| LiDAR St. Malo | |
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Data format: Raster Dataset - GRID File or table name: e724_sm Coordinate system: Universal Transverse Mercator Theme keywords: elevation, environment, geoscientific information |
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Abstract:
One metre LiDAR data was collected in the area of St. Malo, Manitoba. LiDAR data was collected using LSI's proprietary Helix LiDAR system - Novatel GPS and IMAR inertial unit, coupled to a Riegl Q560 digital waveform ranging laser and mounted in a Partinavia P68 Observer aircraft. LiDAR was collected at 600m AGL, and a ground speed of 225km/h. Data is in an ASCII XYZ coordinate format. |
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Metadata elements shown with blue text are defined in the Federal Geographic Data Committee's (FGDC) Content Standard for Digital Geospatial Metadata (CSDGM). Elements shown with green text are defined in the ESRI Profile of the CSDGM. Elements shown with a green asterisk (*) will be automatically updated by ArcCatalog. ArcCatalog adds hints indicating which FGDC elements are mandatory; these are shown with gray text.
One metre LiDAR data was collected in the area of St. Malo, Manitoba. LiDAR data was collected using LSI's proprietary Helix LiDAR system - Novatel GPS and IMAR inertial unit, coupled to a Riegl Q560 digital waveform ranging laser and mounted in a Partinavia P68 Observer aircraft. LiDAR was collected at 600m AGL, and a ground speed of 225km/h. Data is in an ASCII XYZ coordinate format.
The data was collected in order to build an accurate digital elevation model of the study area.
ground condition
none
250, 3115 12th Street NE
This data set was developed for Province of Manitoba by LiDAR Services International Inc.
Ground points were initially classified using an automatic classification routine. The ground surface model was edited and verified by creating a shaded relief model and identifying erroneous points and voids in the ground surface.
Data was verified by viewing shaded relief models. Points were checked against those from adjacent flightlines to ensure positional accuracy. The intensity of the LiDAR returns was viewed and compared against adjacent data to verify horizontal positional accuracy.
Horizontal accuracy is verified by comparison of horizontally identifiable features in the LiDAR data against similar features in another flightline of LiDAR data over the same geographic area.
Vertical accuracy is verified by comparison of points from the calibration flights to conventionally surveyed ground points at the calibration site.
Control point used to build GPS network from which positions of kinematic GPS solution and calibration points were derived. NAD83 published coordinates are Lat: 49 21 43.6085, Long: -97 04 30.8945, Orthometric Height: 239.522m. Adjusted coordinates used for LiDAR positioning are Lat: 49 21 43.60883, Long: -97 04 30.89208, Ellipsoid Height: 212.7914m. This point was occupied during kinematic GPS collection.
Control point used to build GPS network from which positions of kinematic GPS solution and calibration points were derived. Monument is an existing section marker post with brass cap stamped WT13185N. Coordinates established in 2008. Coordinates used for LiDAR positioning are Lat: 49 19 31.15825, Long: -96 51 37.49768, Ellipsoid Height: 242.899m. This point was occupied during kinematic GPS collection.
Control point used to build GPS network from which positions of kinematic GPS solution and calibration points were derived. Monument is an existing steel cap. Coordinates established in 2008. Coordinates used for LiDAR positioning are Lat: 49 33 35.17847, Long: -96 40 35.47991, Ellipsoid Height: 229.499m. This point was occupied during kinematic GPS collection.
Kinematic GPS data was processed using adjusted coordinates. Kinematic GPS and inertial information were combined to create the final position and attitude trajectories. The position and attitude trajectories were combined with data from the scanning laser to produce a raw XYZ point cloud.
250, 3115 12th Street NE
Overlapping flight lines were compared at the calibration site and within the project area to determine the boresight corrections required to remove systematic errors. Raw point clouds were generated using the attitude information and scanning laser ranges.
250, 3115 12th Street NE
Raw XYZ point clouds were combined and divided into 1km x 1km tiles. Redundant data between overlapping flightlines was removed.
#250, 3115 12th Street NE
LiDAR data was adjusted from ellipsoid to orthometric elevation using the CGVD28 height model.
#250, 3115 12th Street NE
An automatic ground classification routine was run on the LiDAR data using TerraScan, and the results were verified by viewing a shaded relief model. Points that existed above ground were classified to vegetation and then buildings were classified manually from the vegetation points using the shaded relief model to identify them. Points that could not be identified as vegetation or ground were classified as non-ground; bridges and transmission lines were classified to non-ground.
250, 3115 12th Street NE
Gridded ASCII XYZ files with a horizontal spacing of 1m were created in TerraScan. Elevations were derived from triangle facets in the TIN model (built using ground points only) at the centre of the grid cell.
#250, 3115 12th Street NE
Gridded ASCII XYZ files with a horizontal spacing of 1m were created in TerraScan representing the ground, vegetation, building, and non-ground points. Elevations were derived from the highest point elevation within the grid cell.
#250, 3115 12th Street NE
Metadata imported.
copied compressed .gz files to local disk unzipped using 7 ZIP created a grid from the first text file to be used as the snap grid CREATETIN GENERATE POINT TINARC POINTGRID ran aml called ld_lidar_grid to generate grids from all text files created a new file geodatabase in ArcCatalog created a raster catalog in the file geodatabase loaded grids into the raster catalog ran the raster catalog to raster tool in the tool box used con(isnull (lidar), focalmean(lidar, rectangle, 3, 3,), lidar) to fill in gaps between the tiles of data. St. Malo full feature grids and bare earth grids were successfully created
The only attributes assigned were point classification during the processing phase using TerraScan. See process steps for details.
None
250, 3115 12th Street NE