The Minnesota Department of Transportation (MnDOT) completed the first portion of a two-phase study to determine if unmanned aerial vehicles (UAVs) could effectively inspect bridges by gathering close-up imagery of structural flaws.
UAVs help access confined spaces that aren’t safe for inspectors to conduct assessments using traditional methods.
The first phase found the technology was able to gather the same data as traditional methods of inspections from the ground using trucks, ladders and lifts. The research team tested drones on four bridges in Chisago, Olmsted, Morrison and Washington counties.
MnDOT will conduct the second phase of the study in November by testing drones on the Blatnik Bridge in Duluth, Minn.
The department spent approximately $35,000 on the first phase of the study and plans to spend around $75,000 from research funds for the second phase. The agency is studying which bridges could be inspected in the future, as well as the safety of a drone program compared to the way bridges are inspected now.
MnDOT is responsible for inspecting more than 20,000 bridges and over 4,500 trunk highway bridges during the inspection season, which runs from April through the end of October.
However, before the agency can use drones on a regular basis, the FAA will have to pass an extended set of drone regulations for commercial use, instead of case-by-case “section 33” exemptions.