Efficient 3D digitalisation of a large casting using a laser scanner
Laser scanners record large measuring volumes, meanwhile with sub-millimetre accuracy. Multiple scans are required to completely scan complex components. They are correspondingly precise and ideally assembling them is fully automated. The procedure is explained using a low-pressure steam turbine housing (Siemens AG, Power and Gas Division, Steam Turbines) as an example and the results are presented.
1 The laser scanner measurement system
Terrestrial laser scanners are very well suited for capturing large structures such as buildings, streets, landscapes and the like due to their range, but they are generally too inaccurate for industrial applications. The Surphaser laser scanner model series delivers hitherto unrivalled measuring accuracy. This series is specifically optimised for shorter ranges and achieves sub-millimetre accuracy. With measurement noise of approximately 25 μm and the small measuring point size, the data quality delivered by the Surphaser is very high. Thanks to the coaxial measurement setup, a laser scanner – unlike triangulating measuring methods (strip projection, photogrammetry and the like) – can also measure inside very deep holes and cavities, and efficiently record complex component geometries.