What's All of the Fuss About HI-DEF Scanning?

When it involves 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 an array of industries from engineering to historic preservation.

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

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

Exactly why is it better? For one, laser scans are incredibly precise. Images are created from a "point cloud" of millions of points that could be measured precisely including the distances and elevations between points. Also, they are versatile. The scans, when used in combination with digital color photos, can produce survey-quality files, videos and even 3D animated computer models and so are so intuitive that even a novice can understand the info.

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 will pay for itself. It is cheaper in the long term because you can revisit the initial scan multiple times from your computer desktop and never have to revisit the project site. Also, as the technology is so precise, the necessity for construction reworks and expensive retrofitting is minimized or removed altogether.

For firms thinking about getting involved with this technology, you can find 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 price of entry into this sort of scanning is normally between $150,000 to $250,000 for the initial units and software. (Although less costly scanners are now available, software packages can still be expensive and the expense of training should also be looked at.)

Aerial platforms and Mobile platforms start at $500,000 and rise to $5,000,000. These units are constantly being upgraded with newer and better digital sensors and data management enhancements. We currently use 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 town of Atlanta and producing 3D models of all the buildings.

If the expense of these units seems intimidating, take into account that firms which have already committed to these technologies are often open to partnering opportunities with smaller firms.

Small scanning targets objects the size of a Volkswagen all the way right down to the mechanical components within a wrist watch. The applications in this field - commonly known as "reverse engineering" - include quality control of manufactured parts or data capture for a manufactured process. A typical project could possibly be scanning an ornate stair rail in order that an exact replica could 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, plus they would all work when re-assembled.

So what can be scanned?

If it could be built, it really is scanned. There's virtually nothing built that can't be duplicated and modeled with current scanning techniques.

As well as the engineering, construction and manufacturing industries, this technology can be 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 also on Hollywood sets. You can find companies that make their living scanning elaborate movie sets before and once 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!