TRIANGULAR 3D LASER SCANNING IN UNDERWATER PHOTOGRAMMETRY

The use of triangular 3D laser scanning may significantly enhance the visual inspection of underwater objects. In these days of high demand for accurate information, exclusively photographic documentation is not enough, as it is geometrically flawed. The authors of this article are trying to present the rudiments of laser scanning, a modern means of measuring, which is reliable, relatively easy to use and works in accordance with basic good measurement practices. With the use of a laser beam, a point model of the measured object is generated with a resolution that is adapted to the requirements. A well performed scan will cover the entire surface of the measured object with no information gaps, as is often the case with photographic documentation which focuses solely on key details. Photographic documentation is now already being replaced by Structure from Motion technology, the latter being an alternative to laser scanning, which creates a textured 3D model from the collection of photographs of the object with similar accuracy, but with more time required.