Targetless Registration: By the numbers by David Dustin

Targetless Registration: By the numbers

David J. Dustin, Eric J. Dustin

Targetless Registration: By the Numbers

•Present a method for validating targetless registration accuracy

•One that can be reproduced by anyone

• Initiate a discussion on other techniques for ensuring the accuracy of targetless registration.

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Targetless Registration: By the Numbers

• A single scan is going to be very accurate (+/- 2mm)

• Greatest potential for error occurs in registration of multiple scans.

• Want to encourage some type of accuracy check in every scanning “opportunity”

• Error isn’t a bad thing as long as you know what it is. Everything has error

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Targetless Registration: By the Numbers

• Love targeted registration

•Hate targeted registration

• Love targetless registration

•Hate targetless registration

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Targetless Registration: By the Numbers

•Have had projects that should have worked targetless and did not

• Long sections of flat roads (did not)

•Hilly section of road (did.. Sort of)

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Targetless Registration: By the Numbers

• Equipment Used for test:

• Faro X330, specially outfitted Dustin Forensics version

• Faro 145mm spherical targets

• Faro checkerboard targets

• Leica DISTO E7500i Laser Distance Meter

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Targetless Registration: By the Numbers

• Faro X330, specially outfitted Dustin Forensics version (kidding)

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Targetless Registration: By the Numbers

• Faro 145mm spherical targets mounted to tripods (about 12 used for the test)

• Faro checkerboard targets printed via laser printer, affixed to flat surfaces via adhesive tape

•Note: checkerboard targets were not used for registration

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Targetless Registration: By the Numbers

• Leica DISTO E7500i Laser Distance Meter

•Mounted to various tripods for stability

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Targetless Registration: By the Numbers

• Method

• Place targets

• Scan area with targets in position

• Perform hand measurements with tape (discontinued due to wind and inaccuracies)

• Perform measurements with Disto

• 3 measurements per target pair, average results

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Targetless Registration: By the Numbers

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Targetless Registration: By the Numbers

•Questions?

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