Geometry of X-ray computed tomography systems: A sensitivity analysis of detector angular misalignments on dimensional measurements

X-ray computed tomography (XCT) is increasingly used in industrial metrology for dimensional measurements of products and components characterized by complex structures, internal features or non-accessible surfaces. However, the accuracy of XCT-based dimensional measurements is affected by several influence factors. One critical factor is the system geometry, i.e. the relative position between the hardware components and their alignment. A number of methods for system calibration based on the characterization of all geometrical parameters have already been proposed in literature, but they are typically time consuming and can be difficult to be implemented by final users. This work is part of a study that aims at evaluating the dimensional measurement errors due to different geometry misalignment conditions, in order to (i) understand the effective necessity to inspect all the parameters and (ii) develop a faster and easier method to control and correct the geometry of a XCT system. The work focuses on a simulation-based sensitivity analysis of detector angular misalignments on XCT dimensional measurements. Each geometrical parameter is studied individually to quantify its effect.