This presentation was given during the 2013 Annual Civil Engineering Conference by Tim Stagg of AeroMetric. It covers system/sensor configurations, application advantages/disadvantages, analysis from sensor data, feature extraction/deliverables, and client pains in relation to survey grade LiDAR technologies for transportation engineering.

1. WELCOME TO THE
ASCE 143RD ANNUAL CIVIL ENGINEERING
CONFERENCE
Survey Grade LiDAR Technologies
for Transportation Engineering

2. Overview
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System / Sensor Configurations
Application Advantages/Disadvantages
Analysis from Sensor Data
Feature Extraction / Deliverables
Client Pains
Questions

3. System/Sensor Configurations
• Mobile Systems
• Helicopter Systems

4. Mobile System Mounting
Can be mounted on most platforms easily
•SUV
•Truck
•Rail Car
•ATV
•Boat
Only requires 12 volt power – marine battery- lasts about 7 to 10
hours with out charge.

5. Mobile Sensor Configuration
GPS and
Inertial Sensors
LiDAR Sensor
DMI
Calibrated
Digital Cameras

6. Mobile Mapper System Configurations
Minimize laser shadowing-optimize field of view (FOV)
• Sensor will see everything behind the vehicle
• Sensor will see ~45° in front of vehicle
• Full 360° area coverage

7. HAMS LiDAR
High Accuracy Mapping System
Helicopter or Fixed Wing
Trimble AP50 Inertial POS system
Equivalent 610 IMU
Phase One IXI 80mp Camera – 55mm lens
800 feet – 1in pixel
Reigl 480i LiDAR Sensor – 550khz
800 feet – Approx. 32ppm single pass
Accuracy – 1 to 2 cm vertically

10. System Advantages/ Disadvantages

11. System accuracies and expected point resolutions
• Fixed Wing
– Can achieve 5 to 9.25cm vertical 1 to
80 points per meter
• Helicopter
– 1 to 3 cm vertical accuracy
– 40 to 150 points per meter
• Mobile
– 1 cm or better depending on control
– 1000 to 4000 points per meter

12. Mobile System Considerations
• GPS receivers are set approximately 16 to 20 miles
apart (no more than 8 to 10 miles from receiver to
MMS unit)
• End data will only be as accurate as the control targets
established
• For high accuracy vertical projects, digital levels must
be established on the targets
• Target spacing should average 800’ between point pairs
• Targets must be placed within sensor view, i.e.
“Roadway”

13. HAM System Considerations
• Target spacing should average 1500’ between
point pairs
• Targets can be placed anywhere within project
corridor

14. Application Advantages/Disadvantages
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Multiple Mission Capability
Rich datasets
Survey coverage limits
Accuracies
Future data usage

15. Mobile LiDAR Advantages Over
Conventional Survey

16. Advantage of
Helicopter for
Shadowed
Vertical
Features

17. Advantage of
Mobile for
Vertical Features

18. HAM Imagery

19. Mobile Mapping Imagery

20. Multiple Data Sources
• A high resolution, geo-coded
digital imagery is collected
with every survey
• Use LiDAR and digital
photography together to
generate true color point
clouds automatically from
scan data

21. Analysis from Sensor Data

22. Bridge Decking Analysis

23. Pot Hole Detection
Cross Section
11” x 21” Pot Hole
2.1 Inches Deep
I-55, Hinds County, Mississippi

24. Pavement Joint Failures
Joint Failure
I-95, Brevard County, Florida

25. Clearance Analysis
Vertical
Clearance
17.56-Feet
Vertical
Clearance
22.60-Feet
Vertical
Clearance
22.43-Feet

26. Slope Analysis
Point to Point Slope
(Water Flow)
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Red – Less than 1% Slope
Yellow – 1 - 2% Slope
Green – 2 - 4% Slope
Cyan – 4 - 20% Slope

27. Slope Analysis
Steel Plate
Pavement Ruts

28. Slope Analysis

29. Classification of LiDAR Point Cloud

30. Elevation by Intensity Color

31. Feature Extraction

32. Traditional Vector Mapping

33. Asset Mapping

34. Points and Line Work

35. 3D modeling of Bridges

36. Point Cloud Rendering/Modeling

37. Feature Collection – Rail Road Corridor

38. Processed Intensity Image

39. Intensity Image fused with RGB Values

40. Point Cloud data fused with RGB Values

41. Client Pains
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Large File Sizes
Rich Data Sets
Difficulty with work Flow Issues
Software always lags behind Hardware

42. Software Solutions
• Dashboards for analysis in 3D environment
• Point Cloud Software for transportation data
• Asset Management Software

43. THANK YOU FOR ATTENDING THE
ASCE 143RD ANNUAL CIVIL
ENGINEERING CONFERENCE
WE LOOK FORWARD TO SEEING YOU
NEXT YEAR IN PANAMA!
Tim Stagg - AeroMetric
Vice President, Transportation Solutions
Phone: (410) 310-9534
Email: tstagg@aerometric.com