Abstract: A method of comparison includes the step (14) of obtaining an interior and exterior image of an object to be compared. A standard of measurements for an acceptable object is created in step (12). An automatic comparison is made in step (14) of the image of the object to be compared with the standard and a comparison report is generated in step (16) listing deviations of the image of the object to be compared from the standard for the acceptable object. An x-ray CT scanner (76) may be utilized for obtaining the images and the standard may be derived from an actual, acceptable object or from design specifications for acceptable objects. In a preferred embodiment, CAD designs are utilized to create the standards for comparison.

Abstract: The present invention relates to a computer tomography system which measures the thickness and edge position of hot-rolled steel. X-rays produced by two X-ray sources are directed, through the sample being measured, to a plurality of radiation detectors. The radiation detectors measure the attenuation of the X-rays caused by the sample. The attenuation levels sensed by each detector are correlated with each detector's physical location. This information is collected as each X-ray source illuminates the radiation detectors. The collected information is triangulated or averaged, as necessary, to determine the dimensions and position of the measured sample.