Development and adaptation of Ultrasonic system for Windblades inspection using Unmanned Aerial Vehicles

Europe is facing one of the most challenging decades with the decarbonization of the energy generation. The increase in the use of energy from renewable sources is essential for the climate and energy global goals. In this way, the optimization of maintenance and repair works of the involved production systems is necessary to reduce costs and time of operation, especially in wind farms, where accessibility is reduced and usually dangerous. For this reason, novel technologies and applications are being investigated in the O&M field like the use of unmanned aerial vehicles (UAVs) for structural assessment of wind blade components through non-destructive technologies (NDT). This is the main goal of DURABLE project, where this investigation is framed. This work is focused on the comparative analysis of different ultrasonic technologies and the development of a protocol for the inspections of wind blades for its application by means of aerial vehicles. The inspections tests have been conducted on samples at laboratory level as a previous work for the post implementation of this technology with drones in field. Diverse UT transducers with 4.0 to 5.0 MHz emission frequencies as well as single element and phased array probes have been used to determine the best configuration for the inspection of each material and thickness of wind blades. To characterize the detectability, artificial defects (impacts and flat-bottomed drills) have been introduced in the test samples to analyze the detectability with manual handled UT inspections. Finally, the most suitable ultrasonic probe was selected, adapted and integrated in an end effector for its implementation in a UAV. The applicability of the inspection by using aerial vehicles has been tested in relevant environment (at laboratory) and in real windfarm.