Using LiDAR Data within Smallworld Mark Field – FCSI

Overview LiDAR – We have heard about it, but what is it? How’s it collected What data is in it Variations of LiDAR data How is it stored in Smallworld Example set of tools How this implementation can be used to develop useful data

What is LiDAR? Light Detection And Ranging aka Laser Detection And Ranging (LADAR) Can be used in side and downward-looking Laser speed gun, weather “radar”, airborne Data is gathered by detecting the reflection of the light Distance, intensity, return number Raw results are “point clouds” Difference btw lidar & radar is basically wavelength. Longer wavelength is “radar” (http://www.wisegeek.com/what-is-the-difference-between-lidar-and-radar.htm)

LiDAR Collection Illustration Source: https://www.e-education.psu.edu/lidar/node/1405

Variations of LiDAR Raw, Unfiltered Data(LAS format) Contains noise, artifacts Filtered, Classified (LAS format) Contains point cloud data Multiple returns Classified into ground, vegetation, building, etc. Ground Points (LAS format) Contains single “layer” of ground Digital Elevation Models (DEM, DTM, TIN) Rasterized version of ground points

Variations of LiDAR (cont.) LAZ Lossless Compressed LAS Categorized XYZ ASCII Files separated into single category

Implementation by FCSI Expanded FCSI’s N-Dimensional Geometry 5+ Dimensional TIN Structure (XYZTV) TIN Node now contains all LiDAR Data X, Y, Z Intensity Return Number of Returns Scan Direction GPS Time Edge of Flight? Classification Scan Angle User Data Point Source Color (RGB)

Example Tools by FCSI Point Viewer DEM Updater Points colored by return, intensity, elevation, classification Filter points by return, intensity, classification DEM Updater Update DEM values based off LiDAR Manual Feature Extraction 4’ imagery.

Point Viewer 4’ imagery 5000’ x 5000’ 7.7Million Points! 2-3” to 1-2’

DEM Update

Elevation Extraction

Issues with LiDAR Number of Points is extremely large 1000’ x 100 ‘ of Missouri contains 560,000 points! 5000’ x 5000’ 5.3 to 8.2 Million points! 5.3 Million = 463MB gdb.ds (1MB rwo.ds) What will it be used for? DEM/TIN – Rasterize externally Ensure data is what you want to use Is it classified? Does it contain non-ground data (multiple returns)? External tools do exist that may be more effective Example data ranges from 2-3” to 1-2’ spacing

How Can LiDAR Be Used? Very accurate terrain models TINs or DEMs Identify features for corridor management Buildings Vegetation Towers, Poles, Lines

Questions?/Contact Mark Field mark@field-csi.com FCSI Booth 19 Cell: 407-376-6105 @mbfbsae90 mbfbsae90