Contour Mapping from LiDAR

1. Contour Mapping from LiDAR Presented by: Dave Bullington Surdex Corporation St. Louis, MO dbullington@surdex.com

2. Surdex Corporation • Surdex headquartered in St. Louis, MO area • Over a half-century of photogrammetric mapping • ~100 employees • 8 aircraft – 4 Cessna 441 (Conquest) Turbine Aircraft • 3 Intergraph Digital Mapping Cameras (DMC) • 1 Microsoft Vexcel UltraCam XP Wide Angle • 5 film cameras • Leica ALS50 II LiDAR Sensor • Very progressive R&D • Large amount of proprietary algorithms and software • Focus on cost-efficiency and performance

3. State of the Art Equipment

4. Surdex Aircraft

5. Surdex’s Client Base • Federal Government USACE,USDA, DNR, USGS, FEMA, EPA • State Government Statewide Programs, DOT’s, SEMA • Local Government County, City, RPC’s • Private Sector Civil Engineering, Real Estate, Development, Mining, Oil & Gas

6. Deliverables • Digital Orthophotography (4 Band) • LiDAR • Planimetric Mapping • Topographic Mapping • Ground Control Survey • GIS Services

7. LASERMeasurements (Range, Angle, Time) LiDAR Processing GPS DataReduction GC Check Position Attitude GPS/IMU Processing IMU X,Y,Z Point Cloud Classification AUTOMATIC Classified Points (Bare-earth, veg/building) 2D Edit LASER Intensity, RGBOrtho Photos MANUAL TIN Stereo QC / Edit DataThinning Stereo Images TIN Break-lines DTM Surface

8. LiDAR Data • First, middle, last return • Position (X,Y) • Elevation (Z) • Intensity • Products • Intensity Image • Digital Surface Model • Digital Terrain Model • Classification • Contours

9. First Returns Second Returns Third Returns Last Returns All Returns

10. Elevation Cross Section

11. Ground Cross Section

12. Bare Earth DEM Calculations • Identify man made structures • Determine ground elevation at edges • 2. Identify vegetated areas • Search for ground points within area • 3. Identify open areas • 4. Interpolate between available points • 5. Filtering and clean-up First Return DEM

13. Automatically extracted Bare Earth DEM • Ground surface with vegetation and man-made structures removed • Critical for terrain and hydrology modeling Bare Earth DEM

14. Bare Earth DEM with 1 meter contours

15. Raw vs. Edited LiDAR Contours Contours from raw LiDAR data Contours from raw LiDAR data with photogrammetric edits

16. Types of LiDAR DTM & Contours • Level I • Classified to Bare earth only, automated • Level II • Classified to bare earth • Automated, minimal cartographic edits • Level III • Classified to bare earth • Break-lines added to hydrology • Similar cartographic edits of Level II

17. Types of LiDAR DTM & Contours • Level IV • Level III plus: • Stereo Compiled Breaklines • Planimetric Features (optional)

18. Level 1-2 surface

19. Level 1

20. Level 1 Surface and Contours

21. Level 2 Contours

22. Level 2 Surface and Contours

23. Level 3 Breaklines

24. Level 3 surface

25. Level 1-2 Surface Level 3 Surface

26. Level 3 Surface and Contours

27. Level 3 Contours

28. Level 3 Contours with Breaklines

29. Level 3

30. Level 4 Photogrammetric Enhanced