Developed by Fraunhofer Institute for Factory Operation and Automation IFF in Magdeburg, Germany, the RIWEA robot is said to register any crack and delamination in the material relaying their exact positions. It also checks the bond with the central strut.
Rotor blades, often made from glass fibre reinforced plastic (GRP), have to withstand wind, inertial forces and erosion and therefore have to be inspected at regular intervals. Rotor blades can be up to 60 m in length and are often placed in inhospitable areas – especially when it comes to offshore wind turbines. This is not a problem for the robot, which can pull itself up ropes and can climb wind turbines of any size, on- or offshore.
The inspection system included in the robot features an infrared radiator conducting heat to the surface of the rotor blade. A high-resolution thermal camera can then record the temperature pattern and thereby register flaws in the material. An ultrasonic system and high resolution camera enable the robot to detect damage hidden to the human eye.