Ask The Experts: Is 3D Surveying Technology The Right Choice For Your Surveying Need?

You need a survey done. Whether ALTA, boundary, construction stakeout, topographic or any other, you may wonder if 3D scanning is the right choice. Our Survey Division would be happy to review your project and advise you on which survey type is best for your particular project, but in the meantime, here’s a quick run-down on the benefits of 3D Scanning surveys by one of our Project Surveyors, Matt Baird.

What kinds of projects benefit from 3D scanning rather than traditional direct survey?

Most projects can be surveyed using 3D scanning technology but here are three specific examples of the kinds of projects for which a 3D scan makes the most sense:

Any urban, close-quarters project. For example, we recently provided full full interior and exterior imagery and data of a two-story building in DC to determine the extent and location of the support structure. For each scan position, we were able to collect data for all the columns and support beams in minutes. This is particularly useful in adaptive reuse buildings for which an old façade will be retained. A 3D scan can inform where the key points of attachment are on the inside of the façade so they don’t disrupt them during construction and renovation.
A busy roadway is a great opportunity to use 3D scanning technology instead of traditional surveying methods. All surface data can be collected without having to set foot on the road. This is such a benefit in terms of safety and expediency. The crew doesn’t need to take the time to dodge or divert traffic and there is a much smaller chance of an accident.
Any confined space area. This is similar to the first point but extends to scenarios that may not be urban but still involve close quarters. For example, manholes, sewer as-builts or even motor pits.

What are the 3 biggest benefits to 3D Scanning vs traditional direct survey?

Less time in the field
More data collected – complex features/locations can be captured all at once
Greater safety for our surveying crews

Recently, we were tasked with surveying metro station escalators for WMATA. To determine the support structure for the existing escalators, our surveyors had to descend into access shafts to get under the escalators to see the support beams. In traditional survey, it would have proven very difficult as establishing conventional “control” points would be challenging and with only one entry/exit points, options were limited. The 3D scan allowed sections of data to be “stitched” together by the software so that all 20-30 scans were joined with overlapping common data and provided a full, overall scan, which could be registered to site control at the surface.

Not only is data provided in the form of a point cloud, but actual imagery is also captured… a full 360 degrees of data and imagery in each scan.

Is 3D Scanning More Cost Effective than Traditional Surveying?

3D scanning is more cost effective for a number of reasons. What used to take several surveyors extended time in the field, possibly standing in traffic, we are now able to perform the field work with a smaller crew in a shorter amount of time.

For example, a scan of an intersection – a topo survey – is dangerous for our field crews to do. In urban areas, they can now scan the intersection quickly, from the side of the road, collect the data to be processed and analyzed in the office. Saving time, reducing risk as well as cost.

More information can be gathered from the 3D model after the fact than you could from an original key points type traditional surveying results. A full 360 degree scan might have taken well over an hour to do 10 years ago; now this same scan takes approximately 2 minutes. Even years later, those 3D scans can still be used to generate data regarding the conditions on the site/location at the time of survey.