Maintenance teams and materials have to travel long distances to reach wind turbines on the high seas. Can drones take over transportation tasks and relieve maintenance personnel? DLR is investigating the possibilities and requirements together with the energy supplier EnBW. In this context, an unmanned DLR small helicopter has now flown to a wind turbine and automatically communicated with the turbine. Seven commercial drone manufacturers will build on the findings to further advance the technology developed at DLR. To this end, DLR and EnBW are organizing the 'Offshore Drone Challenge' at the National Test Center for Unmanned Aircraft Systems in Cochstedt in June 2024.

The wake turbulence of wind turbines can have a major impact on drones. For example, the drone then needs a lot of energy to control the air turbulence. "For automated use in the wind farm, the drone must therefore exchange information with the turbines," says Sebastian Cain from the DLR Institute of Flight Systems Technology, which is leading the project. It is important that the drone and the wind turbine 'understand' each other well. "The drone should find the best route itself. To do this, it needs data from the turbines and wind turbines may have to be stopped so that the drone reaches its destination safely." The interference with the turbine - and therefore with energy generation - should be as minimal as possible.

Communication successfully demonstrated

At the beginning of October 2023, the unmanned DLR 'SuperArtis' small helicopter took off from the EnBW wind farm in Schwienau (Lower Saxony). The helicopter included information on the operating status of the individual wind turbines, weather information and wake turbulence in the calculation of its flight route. The aircraft announced its arrival at a wind turbine via communication interfaces. A simulated control room cleared the approach and the controlled wind turbine stopped. The aircraft was able to approach safely. The system was then reactivated. If the drone had not received clearance, it would have automatically flown into a holding loop. For a realistic scenario, the researchers attached a payload to the aircraft. The experiment did not take place on the high seas, but on land to make it safer and easier to conduct the experiments. "However, the results can be transferred to offshore systems. The communication between the aircraft and the turbine was designed for offshore operation and is being investigated in simulations," explains Sebastian Cain.

Together with the energy company EnBW, DLR is investigating whether the use of drones can simplify logistics for wind turbines on the high seas. Researchers from the DLR Institute of Flight Systems have used the unmanned DLR SuperArtis helicopter for flight tests.

© DLR

The flight test was an important intermediate step in the 'Upcoming Drones Windfarm' (UDW) project by DLR and EnBW. The aim of the project is to find out the conditions and necessary steps for the realization of drone operation, initially for material transport, and in the future also for passenger transport. The project also includes the 'Offshore Drone Challenge' (ODC), at which drone manufacturers and service providers will present suitable solutions. The players can benefit from the current research results. The companies Anavia, Flowcopter, Flying Basket, Hyfly, Nexaero, Unmanned Helicopters and Volocopter have been selected and will be presenting their technologies in Cochstedt in June 2024.

The 'Offshore Drone Challenge'

The challenge in Cochstedt focuses on testing flight maneuvers that are relevant to the operation and maintenance logistics for offshore wind farms. This includes software topics as well as structural modifications to connect the 'drone' and 'wind farm' systems. The challenge will be carried out on land, as this is significantly safer, simpler and more cost-effective than the subsequent application in the middle of the sea. The seven drone manufacturers and service providers can put their technologies to the test over the course of two days. The various stages include tasks such as picking up and setting down the load as automatically as possible or flying beyond visual range.