Electronics

Tower of Pisa 3D-scanned in 20 mins with spring-mounted Zebedee

Tower of Pisa 3D-scanned in 20 mins with spring-mounted Zebedee
The CSIRO's scan of the Leaning Tower of Pisa was completed in under 20 minutes
The CSIRO's scan of the Leaning Tower of Pisa was completed in under 20 minutes
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The CSIRO's scan of the Leaning Tower of Pisa was completed in under 20 minutes
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The CSIRO's scan of the Leaning Tower of Pisa was completed in under 20 minutes
The spring-mounted scanner, Zebedee
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The spring-mounted scanner, Zebedee
The CSIRO's scan of the Leaning Tower of Pisa was completed in under 20 minutes
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The CSIRO's scan of the Leaning Tower of Pisa was completed in under 20 minutes
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Researchers at Australia's national science agency, the CSIRO, have developed Zebedee, a spring-mounted 3D laser scanner and mapper capable of scanning complicated interiors in double-quick time. The researchers were able to scan the "cramped and complex" interior of the Leaning Tower of Pisa which, the CSIRO claims, has not been possible with previous 3D scanning technology. But more significantly, the researchers were able to complete the scan in under 20 minutes.

It's the spring that appears to be the key to the technology. To laser scan any 3D space of any complexity, you have to place your scanner at numerous locations in order to "see" around any obstructions that might be present. The spring allows the scanner to sway from side to side, helping the scanner to peak around detailed obstructions and capture small details from numerous viewpoints, continually capturing data as its carrier moves around the interior.

But the spring also poses problems. When computer software attempts to piece the data together, it's crucial that it knows the location of the scanner at the point of every scan in order to correctly stitch together the incomplete 3D snapshots into a whole model. How do you do that if the scanner is continually carried about, much less lolloping on the end of a spring?

According to the researchers, the device includes an inexpensive inertial sensor which provides "rough" tracking of the rotations of the spring. The team's specially-developed software combines these inertial measurements (along with, presumably, some additional positioning data) and the laser range scanning information to build a 3D point cloud of the space – and in less time than it took to conduct the survey.

It may sound as though this might amount to fuzzier, less accurate models than with traditional static laser scanners, but the researchers claim that this is not the case. "This technology is ideal for cultural heritage mapping, which is usually very time consuming and labour intensive. It can often take a whole research team a number of days or weeks to map a site with the accuracy and detail of what we can produce in a few hours," says Dr. Jonathan Roberts, who leads the program at the CSIRO. He claims that the Pisa model includes small details in the stairways and stonework.

The device is presumably named about the character of Zebedee, a springed jack-in-the-box in the 1960s children's television series The Magic Roundabout.

Source: CSIRO, via Phys.org

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8 comments
8 comments
MBadgero
Too cool. But I can't find a price:)
Mike Bosse
The system does not need any additional positioning data other than the laser ranges and the inertial measurements to produce globally consistent maps.
The device is being commercialized by a UK company: http://www.3dlasermapping.com/index.php/products/handheld-mapping
Sebastian
I was presenting at ILMF in Denver (Feb) earlier this year when the CSIRO team was wandering about with Zebedee, scanning the hall in the morning. They completed that within a couple of hours. Most unfortunate of shaped devices wobbling about in the users hand, but the results point cloud wise, appear like spiders web sprayed over objects and surfaces, meshing into a impressively accurate model. Looking at the above image they have improved on the capture and working with 3D Laser Mapping in the UK, a great bunch of guys, this is sure to do well with exposure in Europe.
Presently the buzzword seems to be archival documentation of heritage sites; the key issue remains rendering them real time, full resolution and on the fly instead of animations.
Przemek Kaszuba
Here : http://www.youtube.com/watch?v=Uj9BKcnXOyo
Aaron Garrett
Wow wait till Google gets there hands on this tech... Not only will you be able to look at your house on Google earth but you can see who's in the shower.
Gregg Eshelman
I bet it'd work even faster if the scanner was mounted on a pole strapped to the operator's back so it could be above head level. Then the person's head and upper body wouldn't block the scan.
Roger Garrett
From the video posted by Kaszuba, it appears that the springs has nothing to do with "helping the scanner to peak around detailed obstructions and capture small details from numerous viewpoints" as stated in the article.
Chris__
There is another video linked at the end of that first one posted by Kazsuba:
It has more info and makes it very clear the spring has nothing to do with avoiding obstacles, but is simply used to tilt the 2D laser scanner up and down to produce a 3D scan. It is an ingenious solution that avoids using a complicated motorised mount to tilt the scanner.
I don't think it would work on a pole strapped to the operator as it would require the operator to control the swinging movement of the scanner to ensure it covers the full vertical range.