Overview. 1. Aerial LiDAR in Wisconsin (20 minutes) 2. Demonstration of data in CAD (30 minutes) 3. High Density LiDAR (20 minutes)

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2 Overview 1. Aerial LiDAR in Wisconsin (20 minutes) 2. Demonstration of data in CAD (30 minutes) 3. High Density LiDAR (20 minutes) 4. Aerial lidar technology advancements (15 minutes) 5. Q & A

3 1. Aerial LiDAR in Wisconsin LiDAR basics History and Current Status Recent Improvements Use Cases

4 What is LIDAR? Light Detection And Ranging Similar to Radar or Sonar but uses an optical source a laser to measure location based on speed of light Produces millions of XYZ points per square mile Aerial Survey Technology Now standard technology for large area topographic mapping

5 Definitions Point Cloud dataset of XYZ points collected from a LiDAR sensor LAS the most common format for storing lidar point cloud data Bare Earth DEM Digital Elevation Model created using ground class points Returns each pulse from the laser sensor can have multiple returns PPM refers to the density of lidar data, Points Per Meter (square) NPS refers to the point spacing of lidar data, Nominal Point Spacing QL2 LiDAR Quality Level 2, which is the current spec for countywide lidar in WI 3DEP 3D Elevation Program run by USGS to achieve lidar coverage across the US

6 Typical Datasets produced from aerial LiDAR Classified Point Cloud Bare Earth DEM Hydro Breaklines 2-ft Contours

7 Common Applications Floodplain Mapping Contour mapping Drainage studies Terrain analysis Feature extraction Engineering planning/design Volumetric measurements

8 Status Map

9 Data Access Full Resolution datasets Point Cloud DEM Contours Breaklines

10 Data Access Public Domain Derived DEM s

11 The last 12 years in Wisconsin

12 Current industry specifications USGS: ASPRS: FEMA: USACE:

13 Current Status

14 Vertical accuracy specifications County LiDAR in WI Pre-2015 Current Point Density 1 PPM 2 PPM Vertical Accuracy 0.61 feet RMSEz 0.33 feet RMSEz Contour Interval 2-foot 1-foot Specification FEMA/USGS v1.0 ASPRS/USGS v1.2 QL2

15 Vertical Accuracy Analysis Calibration Control Non-vegetated, open areas Checkpoint Control Non-vegetated Vertical Accuracy Bare Earth Urban Vegetated Vertical Accuracy Swamp Low Grass Forest

16 Vertical Accuracy Reporting

17 Major improvements in last 12 years Sensor technology More returns per pulse Faster scan frequency Software advancements IT infrastructure = Better vertical accuracy (2X) Better horizontal accuracy Improved point classification Better representation of terrain Greater feature extraction capability

18 1 ppm 1 meter DEM

19 2 ppm 2 foot DEM

20 Older Lidar Density

21 Newer Lidar Density

22 Point Classification Differences

23 Northern Wisconsin Flooding, July 2016 Aid in emergency management planning Measure the amount of material lost Estimate costs for fill material to rebuild the site Understand how water will flow at this site in the future Help to engineer smarter structures for the site

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30 2. Demonstration in CAD Loading points Breaklines Generating a surface Load existing DEMs Creating contours Contour comparisons Loading orthoimage layer

31 Sample Dataset

32 Point Cloud Definitions LAS Classification -

33 3. High Density LiDAR Platforms and sensors High Density Aerial LiDAR demo in CAD Mobile LiDAR demo in CAD Terrestrial LiDAR (HD Scanning) LiDAR point cloud vs. UAV image matching

34 High Density LiDAR Platforms

35 High Density Aerial - DEMO

36 Mobile LIDAR - DEMO

37 Terrestrial LiDAR

38 Terrestrial LiDAR

39 Terrestrial LiDAR

40 LiDAR vs UAV image matching

41 LiDAR vs UAV

42 LiDAR vs UAV Data voids under vegetation

43 LiDAR vs UAV

44 4. Advancements in Aerial LiDAR Single-photon LiDAR (SPL) Geiger-mode LiDAR (GML) Conventional LiDAR systems

45 High density over large areas?

46 Advantages of GML and SPL systems Source: Harris

47 Advantages of Conventional systems

48 When does SPL or GML make sense? Source: Harris

49 When does conventional aerial lidar make sense?

50 Conventional lidar systems advancing too Source: Riegl

51 Impact on the LiDAR industry

52 Impact on the LiDAR industry next 5 to 10 years of choice linear mode is always going to be the sensor

53 Takeaways from today s presentation

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