Terrestrial Laser Scanning Systems

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Terrestrial Laser Scanning Systems

• Sara Walsh

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Overview

• Features
• How laser scanning works
• Time of flight
• Phase Shift
• Operation
• Leica HDS 2500
• Other models
• Applications

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Features of Laser Scanning

• Captures 3D position data of any point
• Dense data acquisition
• Non-contact ? No need for instrumentation of
  sensors on structure
• Ability to capture data for structures that are
  not easy to access
• Reasonably accurate for many applications
• Versatile
• Efficient
• Easy to use

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How Laser Scanning Works

• Time of Flight
• Measures time it takes a laser pulse to travel to
  target and back to determine distance

Image herkules.oulu.fi
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How Laser Scanning Works

• Phase Shift
• Measures change in phase of multiple sinusoidal
  laser pulses to determine time and distance

Image www.optical-metrology-centre.com
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Leica HDS 2500

• Time of flight
• Accuracy 6 mm
• Range Up to 100 m
• Scan rate 1000 pts/s
• Field of View 40 by 40
• Software Cyclone

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Operation

• Set up equipment
• Scanner, computer
• Position targets as needed
• Scan
• Use software for post-processing
• Visualization
• Stitching/Registration
• Meshing

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Other Scanning Systems

• Leica
• HDS 6000
• Faro
• LS 880
• Riegl
• LMS Z420
• Optech
• Trimble
• Price range 70,000-150,000

Faro LS 880
Riegl LMS Z420
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Applications
Historical Documentation
Palace Museum in the Forbidden City in Beijing
Images from www.leica-geosystems.com
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Applications

• ? Survey

Construction Inspection ?
Images from www.leica-geosystems.com
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Applications
As-built documentation ?
? Retrofit
Images from www.leica-geosystems.com
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Applications

• The Big Dig
• Survey
• Closeout drawings

Images from www.leica-geosystems.com
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Applications

• Forensics
• I-35 W bridge in Minnesota
• Riegl LMS Z420

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Questions?