Climbing robotic wind turbine inspector

www.engineering.com
28 Apr 2013

How do you inspect the outside of a wind turbine? Either stand on the ground and use a telescope, or set up some climbing gear and scale the tower. The first solution is imprecise and the second is expensive and dangerous. Both are time-consuming. Now there's a third option: the HR-MP20 Light Weight Magnetic Climbing Robot by Helical Robotics. This remote-controlled robot can scale a turbine tower while carrying up to 9kg (20 lbs) of inspection gear such as cameras and ultrasound. It clings to the tower using five neodymium magnets, the strongest type of permanent magnet available. A technician stands on the ground with a transmitter, directing the robotic inspector to various places on the turbine. (I know-technically that makes it a radio-controlled vehicle, not a robot. The company named it, I didn't.)

The HR-MP20 features a zero turning radius and it can climb at a rate of 20 meters per minute (65 ft/min) and descend at 27 m/min (90 ft/min). It uses a 15 Ah lithium-polymer battery pack for its drive motors, a 10Ah NiMH battery pack to power its payload, and a 4.5Ah NiMH battery for its radio. The radio operates in the 2.4GHz band with a range of 762 m (2500 ft). Its size and capacity can be custom-engineered according to client needs.

Inspecting the blades of a wind turbine requires that the blades be stopped. Using the telescope method, a technician stands away from the turbine and looks at the blades through a telescope. This process can take up to four hours per turbine. Climbing a turbine requires a lot of rope, a strong technician, and a hefty insurance premium. Robotic inspection is faster, safer, less expensive, and more reliable than the telescope or climbing methods. Less down-time translates into more energy production. The HR-MP20 has been proven to work in high winds (which you're likely to find on a wind farm, right?) and bad weather, both of which will delay manual inspections. Of course, you still need a technician to climb up the inside of the tower to perform maintenance on the internal gears, generator, and other moving parts. But the towers have ladders on the inside, and wind is not a factor inside the tower.