Transcript Contour Mapping from LiDAR

Contour Mapping from LiDAR
Presented by:
Dave Bullington
Surdex Corporation
St. Louis, MO
[email protected]
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
State of the Art Equipment
Surdex Aircraft
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
Deliverables
■ Digital Orthophotography (4 Band)
■ LiDAR
■ Planimetric Mapping
■ Topographic Mapping
■ Ground Control Survey
■ GIS Services
LiDAR Processing
GPS
IMU
GPS/IMU
Processing
Position
Attitude
LASER
Measurements
(Range, Angle,
Time)
Data
Reduction
GC Check
X,Y,Z
Point Cloud
Classification
AUTOMATIC
Classified Points (Bare-earth, veg/building)
MANUAL
LASER Intensity,
RGB
Ortho Photos
2D Edit
TIN
Stereo
Images
Stereo
QC / Edit
TIN
Breaklines
Data
Thinning
DTM
Surface
LiDAR Data
■ First, middle, last return
 Position (X,Y)
 Elevation (Z)
 Intensity
■ Products





Intensity Image
Digital Surface Model
Digital Terrain Model
Classification
Contours
First Returns
Second Returns
Third Returns
Last Returns
All Returns
Elevation Cross Section
Ground Cross Section
Bare Earth DEM
Calculations
1. 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 cleanup
First Return DEM
Automatically
extracted Bare
Earth DEM
• Ground surface
with vegetation
and man-made
structures
removed
• Critical for
terrain and
hydrology
modeling
Bare Earth DEM
Bare Earth DEM with 1 meter contours
Raw vs. Edited LiDAR Contours
Contours from raw LiDAR data
Contours from raw LiDAR data with
photogrammetric edits
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
Types of LiDAR DTM & Contours
■ Level IV
 Level III plus:
 Stereo Compiled Breaklines
 Planimetric Features (optional)
Level 1-2 surface
Level 1
Level 1 Surface and Contours
Level 2 Contours
Level 2 Surface and Contours
Level 3 Breaklines
Level 3 surface
Level 1-2 Surface
Level 3 Surface
Level 3 Surface and Contours
Level 3 Contours
Level 3 Contours with Breaklines
Level 3
Level 4 Photogrammetric Enhanced