A University of Missouri-Kansas City (UMKC) professor has partnered with Shafer, Kline & Warren (SKW), a provider of surveying and engineering services, to test what they say is the U.S.’ first tethered drone for bridge inspections.
When Gary Strack, senior project manager at SKW, heard assistant professor of engineering Travis Fields speak on his drone research at the university, he saw an opportunity to use his expertise to test and evaluate new technology in his field.
At UMKC, Fields developed a provisionally patented drone tether system with a battery backup; he spoke about the technology and its applications at a Missouri Society of Professional Engineers – Western Chapter meeting in the spring. At the meeting, Strack approached Fields about using the drone for bridge inspections, and they arranged for the drone to be tested and used at one of SKW’s inspections – the first time a tethered drone has been used for bridge inspections in this country, says SKW.
Fields worked with associate professor of civil and mechanical engineering John Kavern to develop the drone prototype, which is powered by a gas generator and captures footage on a memory card while streaming the footage to a monitor and goggles. During the field test, Fields operated the drone while Strack and SKW project engineer Dustin Berry viewed the live footage and provided direction and feedback.
“The use of a drone would allow us to get to a location on a bridge without putting our personnel in a dangerous situation,” explains Strack. “It also can give us better digital information that we can preserve and use for future inspections.”
“You can fly forever as long as you keep gas in the generator,” he says. “The tether also keeps it close, so if something goes wrong, the tether will break, and you have one or two minutes of backup to land it. Plus, because you are attached to the ground, the tether gets you out of the realm of the [Federal Aviation Administration] where you are considered an aircraft.”
After the inspection, Strack and Berry provided Fields with feedback about camera refinement and adjustments to improve its ability to capture footage of bridge deterioration and corrosion.
“In addition to the camera improvements, we have a few different improvements we are working on for the power system to substantially increase the payload,” says Fields. “I am hoping the next time SKW is out, we can come back out and test again.”