Ramesh L' Shrestha, Bill Carter and Clint Slatton UF

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Airborne Laser Swath Mapping (ALSM)
Ramesh L. Shrestha, Bill Carter and Clint Slatton
UF Bill Dietrich, UC Berkeley UNAVO
Workshop Denver, CO March 14, 2006
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Current ALSM System
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Some Specifications

• Optech Model ALTM 1233
• 33,000 pps
• First and Last Stops and Intensity for each stop
• Automatic Roll Compensator
• Does Not Penetrate Water
• Integrated with Redlake MS 4100 Color Digital
  Camera
• Cessna 337 Skymaster or leased aircraft

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A Principle of ALSM
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Surface Point Spacing
User definable to provide necessary point pacing
on the surface
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NCALM Data Collection Parameters

• One pilot
• One operator
• Cessna 337 Skymaster (8k ft. altitude max. AGL)
• GPS ground crew
• Flying height 600 1,000m AGL
• Flying speed 120 mph
• Swath overlap 50 nominal
• GPS base stations 20 km, min two
• Ground truthing Ground GPS kinematic
• Navigation solution KARS
• Point spacing sub-meter

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Elevation Accuracy ALSM vs Leveling
RMS in Diff. in Elevation 0.06 m
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Elevation Accuracy ALSM vs Photogrammetry
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Accuracy Verification by Ground Surveys
Elevation Accuracy 5 10 cm. Horizontal
Accuracy 30 45 cm.
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The Past
Base Funding for 2 years August 1, 2003 July
31, 2005 Division of Earth Sciences Instrumentati
on and Facility Program
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Present
Funded for Three Years Aug. 1, 2005 July 31,
2008
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NCALM Projects
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Last Mission Aug/Oct, 2005
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Last Mission statistics
Area 1,914 sq. km 478,500
acres LOT 43 hrs Cost 377,620 Cost per
sq. km 197 Cost per acre 0.77
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Some examples
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Eel River
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Flathead Lake, Montana
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Flathead Lake, Montana
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Katalla, Alaska
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Niwot Ridge, CO
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Niwot Ridge, CO
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Steven Gulch, CO
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Big Sky Gallatin Watershed, MT
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www.ncalm.org
Project
Summary
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New Technology
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ALTM 3100
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ALTM 3100 Laser Pulse Rate Operating Altitude
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ALTM3100EA Accuracy Specification
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Digital Sensor System DSS 322
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(No Transcript)
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DSS 322 Flying Height vs Pixel Resolution
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40 miles of Beach Mapping by ALSM Digital
photography was also collected at the same time
Pinellas County, FL
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Seamless Mosaic of Rectified Digital Photography
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Mosaic of Rectified Images
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Accurate High Resolution
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Coastal Area Tactical-mapping System
CATS

• Properties
• Laser wavelength of 532 nm chosen to penetrate
  water
• 800,000 groundals (20x20 cm) per sec
• Overlapping footprints eliminate coverage gaps
• Multi-channel detector will give 20cm contiguous
  spatial sampling
• Multi-event timer electronics will give deep
  returns in vegetation
• 3D sampling vs 2.5D

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CATS Sensor Head
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CATS Ground Test at Sigma Space, Inc.
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Airborne Laser Swath Mapping (ALSM)
Ramesh L. Shrestha and Bill Carter, UF Bill
Dietrich, UC Berkeley UNAVO Workshop Denver,
CO March 14, 2006