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What’s all the fuss about high definition scanning?

When it comes to making precise measurements in complicated environments, high definition scanning – or 3D laser surveying, as it is sometimes called – is quickly making its way to the front of the line in a wide range of industries from engineering to historic preservation.

Engineers use laser scans to work with real-world conditions in complex industrial as-built and plant environments. Construction companies use them to gather precise data on site terrain and renovations, and architects use them to check proposed design models against existing conditions to fine-tune their designs.

Even insurance companies and law enforcement have gotten on board, utilizing the technology to recreate large-scale accident scenes.

Why is it better? For one, laser scans are incredibly precise. Images are created from a “point cloud” of millions of points that can be measured precisely including the distances and elevations between points. They are also versatile. The scans, when used with digital color photos, can produce survey-quality files, videos or even 3D animated computer models and are so intuitive that even a novice can understand the information.

Laser scans are also fast. In 2006, when we bought our first scanner, it took almost an hour to produce a full dome 360 degree scan. Now we can scan in 6-8 minutes. This allows us to take many more scans and capture more detail than we did before.

Scanning almost always pays for itself. It is cheaper in the long run because you can revisit the original scan multiple times from your computer desktop without having to revisit the project site. Also, because the technology is so precise, the need for construction reworks and expensive retrofitting is minimized or removed alltogether.

For firms thinking about getting involved with this technology, there are currently three ways to capture 3D data on large scale projects: Airborne LiDAR (Light Detection And Ranging), Mobile LiDAR, and Terrestrial Scanners, which all produce LiDAR data.

Typical projects for terrestrial scanners are large pipes and tunnels, manufacturing facilities, plant process facilities, airport conveyor systems, bridges, buildings, towers and construction projects. (Our firm focuses on terrestrial jobs, as most cannot be readily scanned from airplanes or cars.)

The cost of entry into this kind of scanning is generally between $150,000 to $250,000 for the first units and software. (Although less expensive scanners are now available, software packages can still be expensive and the cost of training should also be considered.)

Aerial platforms and Mobile Platforms start at $500,000 and go up to $5,000,000. These units are constantly being upgraded with newer and better digital sensors and data management enhancements. We currently work with service contractors on these types of jobs, which are typically focused on documenting civil infrastructure on a much larger scale than terrestrial scans.

Projects could include scanning 100 miles of road to prepare a pavement analysis, mapping 1,000 miles of rail line, or mapping the City of Atlanta and producing 3D models of all the buildings.

If the cost of these units seems intimidating, keep in mind that firms that have already invested in these technologies are often open to partnering opportunities with smaller firms.

Small scanning focuses on objects the size of a Volkswagen all the way down to the mechanical components inside of a watch. The applications in this field – commonly referred to as “reverse engineering” – include quality control of manufactured parts or data capture for a manufactured process. A typical project could be scanning an ornate stair rail so that an exact replica can be created from wood, metal or composite.

This scanning method is so precise that you could dissemble a toaster, rifle or carburetor, scan the parts, manufacture duplicates, and they would all work when re-assembled.

What can be scanned?

If it can be built, it can be scanned. There is virtually nothing built that cannot be duplicated and modeled with current scanning techniques.

In addition to the engineering, construction and manufacturing industries, this technology is also being used by insurance companies and law enforcement to reconstruct accident scenes – like when a highway bridge falls during rush-hour traffic or a multi-car pile-up – and even on Hollywood sets. There are companies that make their living scanning elaborate movie sets before and after they are constructed.

To give you an idea of the wide-ranging capabilities of this technology, in the last month, we have scanned a 120-foot pipe in Chicago, a 737 aircraft in Delaware, a luggage system in LaGuardia, and the interior of a peppermill in Virginia. This technology is everywhere!

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Tate Jones has over 40 years of experience in land and aerial surveying and was one of the country’s earliest adopters of 3D laser scanning technology. A nationally recognized expert in the field of 3D data capture, he has worked with hundreds of clients in the engineering, architectural and construction industries. Contact him at tjones@3DLaserSurveys.com or visit www.3DLaserSurveys.com.

An eight-lane bridge falls into the Mississippi River during rush hour traffic? Yeah – we do that.

A few years ago, an entire span of a busy eight-lane interstate bridge broke apart and fell into the Mississippi River in Minneapolis during rush hour traffic. Cars, concrete, twisted metal and people went crashing into the water.

When the dust settled, 13 were dead and more than 145 injured.

The bridge was Minnesota’s fifth busiest, carrying 140,000 vehicles each day. Eventually, the NTSB cited a design flaw – plus additional weight on the bridge at the time of the collapse – as the likely cause. It was one of the country’s worst infrastructure accidents in history.

When most people think of “forensics,” images of CSI and police dusting for fingerprints immediately come to mind. But do you also think of accident reconstruction and lasers?

In 2007, at the time of the bridge collapse, our firm was one of the first to use 3D laser scanning technology. When we heard about the bridge, we made some calls to the local authorities and offered our scanning services. The response was very positive. (Because of the magnitude of the disaster, the FBI ended-up scanning the site.)

The advantage and need for laser scanning in a case like this is to preserve the scene exactly as it is. On that evening in Minneapolis, the scene was changing, literally, as the rescue was taking place.

Cars were being checked and retrieved, pieces of the bridge were being moved, and all of this was taking place in a river. The precision of high-definition laser scanning and the ability to stay out of the way of first responders and rescue teams was very important.

Once scanned, the data files and photos of the scene could be sent directly to forensic engineers, the Department of Transportation, structural experts, bridge experts and many other engineers and contractors to begin collaborating on the information and building 3D computer models and animation.

Reconstruction is a critical because understanding how the bridge landed could be an excellent predictor of how it originally fell, which could lead to the point of the initial failure and ultimate collapse.

Unfortunately, these types of structural accidents happen all of the time. Recently, there have been several events here in Atlanta where this 3D scanning technology was used or could have been used.

Remember the bus accident on I-75 at Northside Drive, also in 2007? Six were killed when the bus carrying the Bluffton University baseball team tumbled over the highway overpass and hit the ground 30 feet below. The scene was scanned to run a simulation of what might have happened. Investigators later determined that the driver mistook the exit ramp for a lane and went into the curve at full speed.

Or what about the collapse of the elevated pedestrian bridge at the Atlanta Botanical Gardens in 2008 that killed one and injured 18? This is another example of a site similar to the Minneapolis bridge collapse, but on a much smaller scale.

Another example was when a 170-foot section of the railing and fencing along Atlanta’s 17th Street Bridge came loose and crashed to the interstate below in 2011.

All of these are good examples of where 3D laser scanning technology was (or could have been) an excellent choice.

Tate Jones has over 40 years of experience in land and aerial surveying and was one of the country’s earliest adopters of 3D laser scanning technology. A nationally recognized expert in the field of 3D data capture, he has worked with hundreds of clients in the forensic engineering, law enforcement, criminal defense, architectural and construction industries. Contact him at tjones@3DForensicScans.com.