In-line NDT with X-Ray CT combining sample rotation and translation

An alternative acquisition geometry for X-ray computed tomography (CT) is investigated as a solution to in-line non-destructive quality inspection in a high throughput production environment. The sample movement during acquisition combines a translation, typically horizontal, along one axis and a rotation about a second axis perpendicular to the first, and is shown to produce theoretically exact CT reconstructions. A methodology is presented to evaluate the design of a conveyor belt implementation for this acquisition scheme, investigating the trade-off between reconstruction quality and throughput. The methodology was applied in both a simulated version and an experimental mock-up of the conveyor belt implementation for a specific food sample, but can be extrapolated to any type of sample. Throughput, for the food sample, is predicted to be in a practically usable range of up to 5 samples per second. As a general conclusion, higher throughput can be reached with larger inspection stations while maintaining image quality.