Is Drone Data Accurate Enough?
March 30, 2018
Since the FAA issued its first commercial approvals for the use of unmanned aircraft systems, we have watched an industry, burgeoning with enthusiasm, desperately try to convince engineering and survey firms that they should replace other technologies with drone-based remote sensing. As thousands of drone companies launched, the message flooded the market with thunderous volume. And, service providers started competing over whose data had the better resolution and spatial accuracy, exaggerating their capabilities to the point that the many engineers quit listening and quietly went back to work.
But, in the midst of the hype, there exists a game-changing advancement, and every surveyor and engineer should take note. LiDAR technologies are producing digital models of the earth’s surface in a fraction of the time of traditional surveys. And when conducted with the most-advanced sensors, operated by skilled personnel, the data is as good, or better than, traditional survey techniques. The Yellowscan VX, for example, is capable of producing dense datasets with a spatial accuracy of one-tenth of a foot with a 95 percent confidence interval. On many occasions, the data has received a stamp from a licensed surveyor.
Because LiDAR technology is capable of creating models of the bare earth through vegetation, it is very useful for pre-construction surveys. A drone-based LiDAR acquisition can produce hundreds of points of latitude, longitude, and elevation in each square meter of a 500 acre project area in a single day. Most survey techniques would produce only hundreds of points over the entire project area, and the survey would take weeks. The data is converted into formats that are easily digested by design software systems like AutoCad and Microstation.
Because survey is often on the critical path of a construction project, the time-savings of drone-based LiDAR can have a substantial benefit to engineering and construction companies. They are able to get the work done with better quality without cost over-runs and project delays.
To be sure, every good engineering or construction company should be careful in selecting drone-based technologies. There are still a lot of overstatements by a fragmented mass of drone companies. Find a company with real experience working with geospatial data, who has the data processing skills, who is working with the right technology, and can reliably meet your needs. There is no magic bullet, so be wary of unsupported promises. Ask for a trial and be sure that they can substantiate their claims. If you find the right service provider, it could be well worth your while.