Germany is turning to small, flying robots to facilitate the inspection of infrastructure and buildings.

Researchers at the Fraunhofer Institute for Non-Destructive Testing IZFP in Saarbrucken, Germany are pioneering the development and adaption of small flying robots for the purpose of inspecting buildings for damage.

Infrastructure and building quality has become a pressing issue in Germany, where much of the country’s building stock was constructed in the years immediately following the Second World War, and has been subjected to both heavy loads and inclement weather for over half a century.

Inspection of building conditions in a manner which is safe and convenient has become a major challenge for builders and engineers hoping to ensure the safety of these ageing structures.

Test engineers have thus far relied on observation with the naked eye to inspect concrete for cracks. In addition to being a highly fallible procedure, it also necessitates the usage of expensive equipment such as cranes, industrial climbers or even helicopters to observe hard to reach areas.

The development of aerial robots by the Fraunhofer Institute promises to remedy these shortcomings through the use of a device capable of reaching and closely observing those areas which are difficult for human beings to access directly.

Their “octocopter” is a small remote-controlled flying robot equipped with eight rotors and a high-resolution digital camera. The miniature aircraft is capable of drifting and hovering at the whim of its controller, enabling it to scrutinise those parts of buildings which would be impossible for a person to access unaided.

Sensors on the octocopter maintain its stability in fraught wind conditions, ensuring that it remains at the same altitude and doesn’t collide with either buildings or the protruding features of other large structures.

In addition to superior access, the flying robot also confers the advantage of enhanced observation and recording capabilities, using its digital camera to capture a near inexhaustible series of high-resolution images for subsequent examination. These images can then be combined to produce sophisticated 2D and 3D data models which will provide engineers with a comprehensive picture of a building structure, including any cracks or defects in urgent need of remedy.

This imagining capability could be even further enhanced by the incorporation of a thermal imaging camera, which would be capable of assessing the quality of a structure’s insulation set up.

The current prototype, which embarked upon its maiden flight in 2011, vastly reduces the time needed to inspect a building, in many cases free of interference with its normal usage.

According to researchers from the Fraunhofer Institute, the octocopter can inspect a 20 by 80 metre wide facade in just a few hours, as opposed to the two to three days required by a human test engineer.

The team is now working on automation of the robot’s flight pattern so that it will be able to rely on sensors alone to navigate the facades of a building independently as though it were flying on a rail path.