[Image above] C2D2 is a bridge-inspecting robot. Credit: Peter Rüegg / ETH Zürich
Corrosion is a big problem, especially when it comes to the mainstay of modern building materials—steel-reinforced concrete.
While some have proposed alternatives to steel, such as bamboo, to stem the problem in future buildings, there’s still a lot of existent concrete-encased steel around the developed world. Being able to detect damage in structures made of the material before it fails—such as the collapse of a bridge—thus remains a really important job.
(For more about how corrosion infiltrates and compromises steel-reinforced concrete, head over here.)
(And, while we’re on the subject of material failure, a quick sidenote: There’s still time to sign up for one of the ceramic material short courses at MS&T14—whether or not you’re attending MS&T14—which include classes on ceramic failure, electroceramics, or glass science. Sign up here now!)
Swiss researchers at ETH Zürich pioneered a method decades ago to detect damage in steel-reinforced concrete by wheeling an electrode across its surface, the sensor detecting electric potential differences and indicating regions where corrosion was occurring. Similar principles have been used to devise damage-detecting skins, but these remain cost-prohibitive.
While measuring electric potential with a wheeled electrode works really well, it’s labor-intensive, time-intensive, and limited. “The wheel electrode is attached to a stick and has to be wheeled manually,” Bernhard Elsener, professor at the Institute for Building Materials, says in an ETH Zürich press release. “This means that many areas, such as supporting pillars and the undersides of high bridges, lie out of reach.” (Unless, of course, you have a go-go-gadget arm).
So the pioneering Swiss researchers are setting a robot out to perform the task. Pairing with colleagues at ETH Zürich’s Institute of Robotics and Intelligent Systems, the team has tailored a previously designed robot that can walk walls and ceilings—and originally designed to do some fancy filming for Disney—to inspect bridges.
“The robot’s movement is based on Vortex technology, where a type of propeller is attached to the underside of the robot,” states the press release. “The propeller rotates fast enough for a movable suction cup to stick the robot on to walls and ceilings, where it can then use its wheels to move along these surfaces. The robot is steered via remote control or a computer.”
Watch the vid below to see the robot in inspecting action underneath a bridge.
The robot, now aptly named the Climbing Corrosion Detecting Device, or C2D2, has an underneath-mounted electrode that records potential differences as it goes.
And while currently manually controlled with a remote, “The team hope that by the end of the project in mid-2015, the robot will be able to identify and overcome such obstacles by itself,” the release states. The team intends to fit C2D2 with a navigation system and is also working to devise software that would allow C2D2 to analyze its own data, too.
The team has already shown that C2D2 can accurately detect damaged concrete, so with advances that make it autonomous and all-inclusive, this robot could save a lot of money, maintain safer structures, and simplify corrosion detection.