Real inline X-ray 3D CT with short cycle times for light metal casting inspection in production

This paper presents the fusion of X-ray computerized tomography reconstruction and image processing to realize an inline casting inspection system. The approximative inverse is used to derive a nonseparable multiresolution inversion formula in 3D Feldkamp-type cone-beam tomography, i.e. an inversion formula for reconstructing the wavelet approximation and wavelet detail coefficients of the volume slice by slice. The algorithm supports progressive reconstruction and local tomography for recovering only the regions of interest inside the investigated volume. These regions are determined by an image processing step during reconstruction. The features of the reconstruction algorithm are shown by means of simulated data as well as measured data of an aluminium casting from automobile industry.