New articles published: V. 14 n. 3 (2026)

Modeling and Implementation of an Automated Gamma Radiography Inspection System with Robotic Positioning and Bidimensional Radiative Mapping in Cartesian Coordinates

Abstract: This work presents the engineering architecture and controlled radiometric evaluation of a gamma-ray inspection system conceived for Cartesian X-Y automation in non-destructive testing of metallic plates. The architecture combines a Cadmium Zinc Telluride (CZT) detector, a collimated Cesium-137 source, lead shielding, Cartesian positioning, and computational mapping. The radiometric dataset reported here was acquired before complete motion integration: the source and detector remained fixed while aluminum plates of nominal 200 x 200 mm and 1 mm or 2 mm thickness were manually repositioned over a 4 x 4 grid. Three consecutive count-rate readings were averaged at each of the sixteen points and corrected using the recorded point-specific background. The resulting net count rates were associated with Cartesian coordinates and displayed as non-interpolated two-dimensional maps. Net count rates ranged from 1206.00 to 2213.67 cps for the 1 mm specimen and from 1538.00 to 2264.67 cps for the 2 mm specimen. Within each specimen, grouped values increased with the inferred open-hole condition; however, the two thickness series were non-monotonic and cannot be interpreted as an isolated thickness effect. For 662 keV photons in aluminum, the ideal narrow-beam Beer-Lambert model predicts transmissions of approximately 98.0% and 96.1% for 1 mm and 2 mm, respectively. Because a no-sample reference and complete pointwise uncertainty data were not available, absolute thickness, detection limit, and statistical significance were not claimed. The study therefore validates the acquisition-background-coordinate-mapping workflow and defines the metrological requirements for subsequent validation of the fully automated platform. Read full article.