Thermal imaging shows temperature changes in the concrete. Image via KARE11.COM
The Minnesota Department of Transportation is testing the use of drones to inspect bridges.
Transportation officials expect the technology will save money and provide another perspective on how the state's bridges are holding up, KARE-TV reports. The drone allows inspectors not only to see the bridge, but to detect temperature changes in the concrete.
“The biggest benefit is just being able to get out into places that we can't get up close without a lot of equipment or a lot of access methods,' said Barritt Lovelace, an engineer of Collins Engineers.
MnDOT is contracting with Collins Engineers to test the drones.
For bridge inspections, MnDOT typically uses trucks, which cost about $675,000 each and can reduce or shut down traffic. A drone would cost $40,000 and wouldn't cause traffic backups, according to Scott Theisen, a MnDOT engineer.
“There's always more we can do, and this is an effort to try and do a better job, and try and improve our inspection technique,' Theisen said, but noted that drones will never replace a real inspector.
MnDOT will begin its final phase of drone testing this spring and could begin using them full-time next year.
There are more than 20,000 bridges in Minnesota that require inspection, according to MnDOT.