3D Laser Scanning3D Laser Scanning

Eric SchmiedlEric Schmiedl

What does it do?What does it do?

How does it work?How does it work?

What is it useful for?What is it useful for?

Surveying and mapping existing geography Surveying and mapping existing geography Tracking excavation workTracking excavation work Documenting structures as builtDocumenting structures as built Planning renovations to existing structuresPlanning renovations to existing structures

Geography and mappingGeography and mapping

Some 3D scanners can create 3D models of Some 3D scanners can create 3D models of the geography in a 1km radius around the the geography in a 1km radius around the scanner as seen from the scan pointscanner as seen from the scan point

Generate 1 million++ data points in several Generate 1 million++ data points in several hours, vs. tens or hundreds of data points hours, vs. tens or hundreds of data points with hand surveyingwith hand surveying

Accurate representation of intricate textural Accurate representation of intricate textural detaildetail

Tracking excavationTracking excavation

3D excavation site geometry is usually 3D excavation site geometry is usually unknown -- only certain points normally unknown -- only certain points normally measuredmeasured

Laser scan can track ground deformation Laser scan can track ground deformation due to equipment movement & soil removaldue to equipment movement & soil removal

Allows prediction of construction-related Allows prediction of construction-related ground movementsground movements

Allows precise measurement of removed Allows precise measurement of removed earth volumeearth volumeNew Technologies for Tracking Urban Excavation Progress and Estimating DeformationsY. M. A. Hashash, L. Y. Liu, J. Ghaboussi, C. Marulanda, Y. Y. Su, H. Song, and A. Osouli, ASCE Conf. Proc. 199, 41 (2006)

Tracking excavationTracking excavation

QuickTime™ and aTIFF (LZW) decompressor

are needed to see this picture.

Laser scan can track ground deformation due to equipment movement and soil removal

Tracking excavationTracking excavation

Excavation progress measurement

QuickTime™ and aTIFF (LZW) decompressor

are needed to see this picture.

Tracking excavationTracking excavation

Allows precise measurement of excavated Allows precise measurement of excavated materialmaterial Volume of material removed each day easy to Volume of material removed each day easy to

calculatecalculate Accurate and timely estimate of job progressAccurate and timely estimate of job progress Material volume can become basis of paymentMaterial volume can become basis of payment

Documenting constructionDocumenting construction

As built documentation required in case As built documentation required in case original design documents not updated with original design documents not updated with change orderschange orders

Traditional hand measurements slow and Traditional hand measurements slow and laboriouslaborious

3D scanning creates a CAD model quickly 3D scanning creates a CAD model quickly and with relatively little effortand with relatively little effort

Planning constructionPlanning construction

When renovating a structure, accurate When renovating a structure, accurate models are needed to design and visualize models are needed to design and visualize changeschanges

3D data produced by laser scanning can be 3D data produced by laser scanning can be used to create 3D physical models through used to create 3D physical models through rapid prototypingrapid prototyping

Integrating Laser Scanning and Rapid Prototyping to Enhance Construction ModelingJim Goedert, John Bonsell, and Fasineh Samura, J. Arch. Engrg. 11, 71 (2005)

DisadvantagesDisadvantages

Cost and complexityCost and complexity 300+ hours of training required300+ hours of training required Almost $1 per linear foot more expensive (in Almost $1 per linear foot more expensive (in

geographic studies) than aerial photogrammetrygeographic studies) than aerial photogrammetry