How does Cornis rebuild wind turbine blade geometry?
To have a complete and easy overview of your blades, at Cornis we have developed machine learning tools to automatically rebuild calibrated panoramas of your blades. In this article I will give you a sneak peek of how we automatically transform all the images you take on site into a complete blade reconstruction.
First, we identify the order the images are taken in. We use a diversity of image metadata, UAV or Panoblade metadata too. That is the easy part.
Then we have to precisely position and stitch the images together. That is the difficult part.
For many years now, a large variety of algorithms have been developed to do so and we all have a few on our smartphones to enable us to make magnificent vacation panoramas. Such algorithms identify three common points between 2 successive images and overlay them. The problem with these classical algorithms is that they need allot of texture in images and are made to build pretty reconstructions and not geometrically exact ones. With wind turbine blades we have very little texture in the images. And for blade inspections we need to know precisely where a defect is, not just have a pretty panorama. For these two reasons we had to develop our own tools.
To solve this problem, we use a large diversity of tools. With machine learning and artificial intelligence, we can use the very large data-base of reconstructed blades we have to help the algorithms out. Indeed, we have been able to identify patterns in the manner images are taken and overlap in wind turbine panoramas. This gives us a sort of advanced pre-positioning of the images. This allows to reduce drastically the complexity of the problem we are trying to solve and the number of possible combinations. This saves computation power and time and allows us to resolve most of the blade reconstructions we have to do.
Why is it so efficient? It is like building a puzzle with pieces that all look the same. If you have no idea where each piece goes it is going to take allot of time. However, if you know approximately where each piece goes, you will build the puzzle much faster!