Leonard N. Grossman

AUTOMATED INSPECTION SYSTEM

An automated inspection system for manufactured parts is proposed using a cloud of 3D measured points of a part provided by a range sensor, and its CAD model. In spite of the high precision attained by coordinate measuring machines (CMM), range sensors offer significant advantages for dimensional inspection: a high speed of digitisation and the capacity to take 3D measurements on the whole surfaces of a part without physical contact. The system first registers a cloud of 3D points with a CAD model of the part, then segments the 3D points in different surfaces by using the CAD model, and finally measures the control of the specified tolerances on the part. Results of the inspection are displayed in two ways: visually, using a colour map to display the level of discrepancy between the measured points and the CAD model, and a hardcopy report of the evaluation results of the tolerance specifications. Two range sensor technologies have been tested and inspection results are compared with the results obtained with a CMM.

Superconducting magnetometer for quality control of nuclear fuel rods

A superconducting magnetometer is used to assay gadolinium in uranium dioxide nucear fuel rods. Less than 10 percent by weight gadolinium is present in solid solution in the fluorite phase to provide power flattening and to extend the time between refueling of nuclear reactors. The magnetometer is part of an automated rod scanner which provides quality inspection of more than 50 000 fuel rods per year. The magnetometer can resolve a single out‐of‐specification gadolinia pellet (10 g of UO2 with a maximum of 10% Gd) with as much as 0.2 percent by weight ferromagnetic impurity. The measurement techniques considered during development of the scanner were neutron methods, x‐ray fluorescence spectroscopy, modulated‐field magnetometry, and moving sample magnetometry. The latter technique was applied by moving the fuel rod at speeds of about 5 cm/sec through two regions of different static magnetic field in excess of 20 000 oersteds. Each region contains a sampling coil which detects changes in magnetization wit...