Unmanned Aircraft Systems (UAS) Impact on Operational Efficiency and Connectivity

Over the last several years, the use of unmanned aircraft systems (UAS), commonly referred to as drones, has increased significantly. This report outlines the findings of a study to explore the benefits of UAS technology when deployed at the South Carolina Department of Transportation (SCDOT), specifically focused on the areas of land surveying and bridge inspection. The results of a drone-based land survey experiment found that given common field conditions, survey points could be within 0.68cm (.022 feet) (XY), 0.09cm (.003 feet) (Z) and 1.46cm (.048 feet) (XYZ) of the true location. As a natural extension of this experiment, it was found that computed stockpile volume estimates ranged between 1.5% and 3.3% of actual. To evaluate how effective UAS where at supporting bridge inspections, a test bridge was inspected twice using two different bridge inspection engineer (BIEs). Over 90% of the inspection points could be sufficiently observed using a drone. A significant advantage of drone deployment was the reduced need for under-bridge inspection trucks (UBIT), convenient documentation, keeping the BIEs away from traffic and the process being nearly invisible to the traveling public. The experiment also found an estimated cost savings of approximately $1,500 due to the reduced need for UBIT and traffic control. Limitations of the technology included the lack of tactile contact, observing deficiencies at difficult angles near obstructions and flying in global positioning system (GPS) denied environments. The BIE felt that the advantages of the technology outweighed the limitations and supported further investigation in the future. This report also elaborates on a proof of concept experiment conducted to evaluate the possibility of inspecting a bridge remotely via a 4G cellular live stream broadcast. The remote BIE felt that this was a successful workflow and that this technology could be used to inspect bridges successfully with similar advantages and limitations previously described. It was found that inspecting bridges remotely added additional complications to the process including insufficient connectivity to stream the video, excessive latency in video and voice command and the reliance on leading-edge hardware and software that was not always reliable.


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Figures; Photos; References; Tables;
  • Pagination: 86p

Subject/Index Terms

Filing Info

  • Accession Number: 01743993
  • Record Type: Publication
  • Contract Numbers: 69A3551747117
  • Created Date: Jun 25 2020 9:48AM