Example 1: Static Datum
EXAMPLE 1: Static Horizontal Datum with Orthometric Vertical Datum using RTX Refined Reference Station Coordinates (@ L1 Phase Center)
Data Collected : 06/18/21
Desired output for LAS/LAZ: NAD 83 (2011) 2010.000 UTM 14 North Meters, NAVD88 - Geoid18
Horizontal Datum: NAD 83 (2011) 2010.000 UTM 14 North Meters
NAD 83 is the North American Datum of 1983 and is fixed and stable relative to the North American tectonic plate.
NAD 83 = Datum
(2011) = Realization
2010.000 = Epoch
UTM 14 North = Map Projection
Meters = Units
Vertical Datum: North American Vertical Datum of 1988 (NAVD88) – Geoid18
Note: Orthometric vertical datum’s require user to select a geoid model.
For the United States, the GEOIDxx geoid models as been developed based on observations by NOAA’s National Geodetic Survey (NGS).
These geoid models (e.g., GEOID 99, GEOID 03, GEOID12, etc.) provide the geoid undulation parameter (geoid height), so that the ellipsoid height from the NAD 83 three dimensional datum can be directly converted to the NAVD 88 orthometric height.
Navlab and LiDARMill Workflow
Project CRS Georeferencing
During project creation, select "NAD83 (2011)" as the project datum and select "Metre" for the project units.
Next, select the Horizontal coordinate system "NAD83(2011)/UTM zone 14N" (Datum and Map Projection) and NAVD88 (orthometric vertical datum) as the vertical coordinate system + GEOID18 (Geoid model)
GCP Georeferencing
The project CRS should match the GCP CRS. You can verify the GCP CRS by clicking on the "GCP" tab within LiDARMill, and then clicking the button to the right of the GCP artifact, then click "Edit artifact"
Reference Station Georeferencing
In step two of a Navlab Pipeline, select the NAD83(2011) refined trajectory. Navlab will automatically specify the epoch as 2010.000
Output Trajectory Georeferencing
In step three of a Navlab Pipeline, select the output datum as NAD83(2011)
Export Pointcloud Georeferencing
LiDARMill may prompt the user to select the output coordinate system within the Spatial Fuser Pipeline. If it does not prompt the user, the Project CRS will be used.
Inertial Explorer and SpatialExplorer Workflow
Project CRS Georeferencing
Open the Project PLP in SpatialExplorer, and click on the datum at the upper right to configure the datum as NAD83(2011) and manually input the epoch as "2010.000".
GCP Georeferencing
When importing GCPs into Spatial Explorer, Select the Horizontal CRS as "NAD83(2011) / UTM zone 14N" with units set to "metre" and select the Vertical CRS as "NAVD88 height" with units set to "metre".
Also select the desired Geoid18 geoid model.
Reference Station Georeferencing
During trajectory processing in Inertial explorer, configure the reference station datum as "NAD83(2011)" and the epoch as "2010.000".
Output Trajectory Georeferencing
In Inertial Explorer, select the datum "NAD83 (2011)" during the GNSS trajectory processing step
In Inertial Explorer, select the datum "NAD83 (2011)" during the tightly coupled trajectory processing step
Load Post Processed Trajectory into SpatialExplorer
When importing a post processed trajectory into SpatialExplorer, input the trajectory epoch as "2010.000"
Export Pointcloud Georeferencing
When exporting the final pointcloud, select the Horizontal CRS as "NAD83(2011) / UTM zone 14N" with units set to "metre" and select the Vertical CRS as "NAVD88 height" with units set to "metre". Also select the desired Geoid18 geoid model.
