A sensitivity analysis of the rotation stage misalignments effect on X-ray computed tomography dimensional measurements

X-ray computed tomography (CT) is increasingly used in manufacturing metrology thanks to its advantages including the capability of performing non-destructive measurements of both accessible and non-accessible complex geometries. However, the accuracy enhancement of CT-based measurements still represents a major challenge due to the complexity and large number of influence factors. This work is part of a study focused on the enhancements that are achievable by monitoring and correcting the system geometry, through the inspection of several parameters describing the relative position and orientation between the hardware components. In particular, the work has been planned to achieve a complete knowledge and comprehension on the geometry-dependent effects on CT results in order to develop a fast and easy-to-implement procedure for CT systems geometry characterization and correction. At the scope, a sensitivity analysis was designed to investigate the relationship between the deviation of geometrical parameters from the optimal/aligned configuration and the accuracy of dimensional measurements, with the aim of identifying the most critical parameters to be investigated and corrected. This work is focused on the specific effect of rotation stage misalignments, which were investigated separately from the other possible geometrical misalignments.