Brown County, WI LiDAR 2010

Metadata:
Identification_Information:
Citation:
Citation_Information:
Originator: Ayres Associates Inc.
Publication_Date: 20100417
Title:
Brown County, WI LiDAR 2010
Geospatial_Data_Presentation_Form:
Description:
Abstract:
This project is for planning, acquisition, processing, and derivative products of lidar data to be collected for Brown County, Wisconsin. Specifications listed below are based on the US Geological Survey National Geospatial Program Base Lidar Specification, Version 12.”

Brown County Wisconsin has a requirement for LiDAR covering the entire county to be collected at a nominal pulse spacing (NPS) of 1.2 meters.
Purpose:
The Brown County, WI LiDAR project is to provide high accuracy bare-earth processed LiDAR data suitable for Brown County, WI.

The project consisted of acquisition, post-processing, and classification of LiDAR data.  The classified bare-earth data achieved the following:  Vertical accuracy was to achieve a RMSE Z of 15cm (95% confidence level of less than 30cm) or better in the "Open Terrain" land cover category.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 20100330
Currentness_Reference:
ground condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency: unknown
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -88.260
East_Bounding_Coordinate: -87.750
North_Bounding_Coordinate: 44.678
South_Bounding_Coordinate: 44.238
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: Light Detection and Ranging
Theme_Keyword: LiDAR
Theme_Keyword: Bare Earth
Theme_Keyword: Point Cloud
Theme_Keyword: DEM
Theme_Keyword: breaklines
Theme_Keyword: Intensity
Place:
Place_Keyword_Thesaurus: None
Place_Keyword: US
Place_Keyword: State
Place_Keyword: Wisconsin
Access_Constraints: To be determined by client
Use_Constraints:
To be determined by client
Data_Set_Credit:
Ayres Associates
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Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:











Logical_Consistency_Report:









Completeness_Report:


Complete





Positional_Accuracy:






Horizontal_Positional_Accuracy:








Horizontal_Positional_Accuracy_Report:


All data products were acquired at 1700 meters above mean terrain (AMT) with a nominal point spacing of 1.2 meters.









Vertical_Positional_Accuracy:








Vertical_Positional_Accuracy_Report:


The Fundamental Vertical Accuracy (FVA) of the Classified Bare Earth for the Brown County project achieved 0.604 feet at a 95% confidence level in the "Open Terrain" land cover category. 521 control points were used in this evaluation.













Lineage:






Process_Step:








Process_Description:


The LiDAR data was captured using an Aero Commander 500 Shrike, Piper Navajo 310, and Cessna 320 Skynight (twin-piston), fixed wing aircraft equipped with a LiDAR system.  The LiDAR system includes a differential GPS unit and inertial measurement system to provide superior accuracy.

Acquisition parameters:  
1. Scanner - ALTM Gemini LiDAR  
2. Flight Height - 1700 meters above mean terrain
3. Swath Width - 32 degrees
4. Sidelap - 50%
5. Nominal Post Spacing - 1.2m

GPS and IMU processing parameters:  
1. Processing Programs and version - Applanix POSPac, version 4.4  
2. Maximum baseline length - Not greater than 40km.
3. Number of base stations during LiDAR collection - A minimum of 3.  
4. Max separation between base stations during LiDAR collection - 0.10m  
5. IMU processing monitored for consistency and smoothness - Yes.

Point Cloud Processing:  
1. Program and version - Optech ASDA Processor  
2. Horizontal Datum - NAD83  
3. Horizontal Coordinates - WISCRS Brown County, in US Survey Feet.
4. Vertical Datum - NAVD88  
5. Geoid Model used to reduce satellite derived elevations to orthometric heights - NGS Geoid09.

LIDAR Processing:  
1. Processing Programs and versions - TerraSolid TerraScan (version 010.017), TerraModeler (version 010.005 and TerraMatch (version 010.011) and Intergraph MicroStation (version.08.05.02.55).
2. Point Cloud data is imported to TerraScan in a Microstation V8 (V) CAD environment on a specified 5000 foot by 5000 foot tiling scheme.
3. Analyze the data for overall completeness and consistency.  This is to ensure that there are no voids in the data collection.  
4. Inspect for calibration errors in the dataset using the TerraMatch software.  This is accomplished by sampling the data collected accross all flight lines and classify the idividual lines to ground.  The software will use the ground-classified lines to compute corrections (Heading, Pitch, Roll, and Scale).  
5. Orientation corrections (i.e. Calibration corrections) are then applied (if needed) to the entire dataset.  
6. Automatic and manual ground classification is performed using algorithms with customized parameters to best fit the project area. 
7. The Ayres/Aerometric team captured QA/QC points in 'open terrian' land cover category that were used to test the accuracy of the LiDAR ground surface.  TerraScan's Output Control Report (OCR) was used to compare the QAQC data to the LIDAR data. This routine searches the LIDAR dataset by X and Y coordinate, finds the closest LIDAR point and compares the vertical (Z) values to the known data collected in the field.  Based on the QAQC data, a bias adjustment was determined, and the results were applied to the LIDAR data.  A final OCR was performed with a resulting RMSE of 0.308 ft for the project.  
8. Once the automatic processing and testing of LiDAR is complete, the bare-earth surface data was closely inspected to insure that proper classification was achieved as part of a Quality Control process. 
9. Final deliverables are generated and output to a client specified PLSS tiling scheme.





Process_Date:
20100417










Cloud_Cover:
Unknown







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Spatial_Data_Organization_Information:






Direct_Spatial_Reference_Method:
Point







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Spatial_Reference_Information:






Horizontal_Coordinate_System_Definition:






Planar:






Map_Projection:






Map_Projection_Name:
WISCRS - Brown


Transverse_Mercator:






Scale_Factor_at_Central_Meridian:
1.00002


Longitude_of_Central_Meridian:
-88.0


Latitude_of_Projection_Origin:
43.0


False_Easting:
103674.333


False_Northing:
15091.833










Planar_Coordinate_Information:






Planar_Coordinate_Encoding_Method:
coordinate pair


Coordinate_Representation:






Abscissa_Resolution:
0.01


Ordinate_Resolution:
0.01






Planar_Distance_Units:
survey feet










Geodetic_Model:






Horizontal_Datum_Name:
North American Datum of 1983


Ellipsoid_Name:
Geodetic Reference System 80


Semi-major_Axis:
6378137.000000


Denominator_of_Flattening_Ratio:
298.257222










Vertical_Coordinate_System_Definition:






Altitude_System_Definition:






Altitude_Datum_Name:
North American Vertical Datum of 1988


Altitude_Resolution:
0.01


Altitude_Distance_Units:
survey feet


Altitude_Encoding_Method:
Explicit elevation coordinate included with horizontal coordinates















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Metadata_Reference_Information:






Metadata_Date:
20101124


Metadata_Contact:






Contact_Information:






Contact_Organization_Primary:






Contact_Organization:
Aerometric, Inc.






Contact_Address:






Address_Type:
Mailing and physical address




Address:


1802 Pankratz Street





City:
Madison


State_or_Province:
WI


Postal_Code:
53704


Country:
US






Contact_Voice_Telephone:
(608) 443-1200


Contact_Facsimile_Telephone:
(608) 443-1250


Contact_Electronic_Mail_Address:



Hours_of_Service:
Monday through Friday 8:00 AM to 5:00 PM (Central Time)










Metadata_Standard_Name:
FGDC Content Standard for Digital Geospatial Metadata


Metadata_Standard_Version:
FGDC-STD-001-1998







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