Dimensional Metrology with X-Ray Computed Tomography Helical Scanning

With the increasing applications of X-Ray Computed Tomography in the industrial metrology field, the use of helical scanning trajectories is becoming of growing interest thanks to the benefits that they provide, such as the possibility to scan parts that exceed the field of view of the detector vertically and the elimination of cone-beam artifacts. This study provides a comprehensive analysis on the suitability of helical scanning trajectories for dimensional metrology applications and compares metrological characteristics calculated in accordance with the VDI VDE 2630 Part 1.3 to traditional scanning trajectories results. In the experimental investigation, multiple calibrated artifacts are used, as well as systems with different cone angles. An industrial part featuring multiple dimensional and geometric characteristics is also used in the analysis. Experimental results prove the suitability of helical scanning for dimensional metrology applications and lead the path for metrological performance verification of CT systems using helical scanning trajectories.