Figure 10. (a) The image shows a section of the wind blade with delamination damage after the fatigue experiment. The four areas of delamination on the spar cap can clearly be identified by visual inspection. (b) Four inspection images of the delamination areas are mapped to the CAD model of the wind blade. The blue points indicate the positions of acoustics emission sensors, which can be also mapped to the visual digital twin.
Concluding remarks
This study has developed and demonstrated a methodology to create a visual 3D Digital Twin of large-scale structures mapped with precise defects/damage detected in inspection images. The visual Digital Twin allows a detailed representation of the size, location, and shape of unique damage found in the structure. The methodology is demonstrated on a transition piece and a rotor blade of wind turbines to showcase the new functionalities beyond the current state-of-the-art technologies, making it possible to perform a 3D mapping of small damages with the correct shape and size on large-scale structures. The image processing techniques together with the new projection along the surface normals method result in an accurate Digital Twin model. The usability of the Digital Twin could be strengthened by adding more layers of data from other inspection techniques, such as thermography, and data obtained from sensors installed in the structure, such as strain gauges and accelerometers.