Abstract: A computed tomography (CT) reconstruction method includes implementing an iterative image reconstruction process for CT metrology of an object, wherein the iterative reconstruction process utilizes accurate forward projection. During each of a plurality of iterations, a reconstructed image is constrained by utilizing prior outer edge information obtained from a modality in addition to CT, and then transformed to a projection domain so as to generate a calculated sinogram. A correction image is determined based on the calculated sinogram and a measured sinogram.

Abstract: A method for reconstructing image data from measured sinogram data acquired from a CT system is provided. The CT system is configured for industrial imaging. The method includes pre-processing the measured sinogram data. The pre-processing includes performing a beam hardening correction on the measured sinogram data and performing a detector point spread function (PSF) correction and a detector lag correction on the measured sinogram data. The pre-processed sinogram data is reconstructed to generate the image data.

Abstract: A computed tomography (CT) reconstruction method includes implementing an iterative image reconstruction process for CT metrology of an object, wherein the iterative reconstruction process utilizes accurate forward projection. During each of a plurality of iterations, a reconstructed image is constrained by utilizing prior outer edge information obtained from a modality in addition to CT, and then transformed to a projection domain so as to generate a calculated sinogram. A correction image is determined based on the calculated sinogram and a measured sinogram.

Abstract: A method for performing geometric dimension and tolerance stack-up analysis for an assembly, the method comprising receiving a target assembly dimension for stack-up analysis, where the assembly includes at least one part. The method further comprises receiving a feature corresponding to the part and receiving feature tolerance data associated with the feature. The feature tolerance data includes at least one of size tolerance and geometric tolerance. Stack-up rules are accessed in response to receiving the feature tolerance data. The stack-up rules include instructions to determine if a form tolerance, an orientation tolerance and a profile tolerance should be included in a stack-up tolerance for the feature. The stack-up rules also include formulas to calculate a nominal dimension and the stack-up tolerance for the feature when the feature tolerance data applies to features of sizes.

Abstract: A method for performing geometric dimension and tolerance stack-up analysis for an assembly, the method comprising receiving a target assembly dimension for stack-up analysis, where the assembly includes at least one part. The method further comprises receiving a feature corresponding to the part and receiving feature tolerance data associated with the feature. The feature tolerance data includes at least one of size tolerance and geometric tolerance. Stack-up rules are accessed in response to receiving the feature tolerance data. The stack-up rules include instructions to determine if a form tolerance, an orientation tolerance and a profile tolerance should be included in a stack-up tolerance for the feature. The stack-up rules also include formulas to calculate a nominal dimension and the stack-up tolerance for the feature when the feature tolerance data applies to features of sizes.