Abstract: A rotor assembly comprised of a multiplicity of blades mounted around the periphery of a disk has the blade tips ground to great diametrical precision when the assembly is rotated at a high speed in excess of 1000 rpm in a special grinding process. Individual blade lengths are dynamically measured while the assembly is being ground. These measurements are used to control the grinding process and to also permit accurate assessment of the quality of assemblies in general. A laser triangulation measurement system is used. It is capable of very fast reading of blade length since 3300 or more blades may pass by the measuring point each second.

Abstract: A method and apparatus for inspecting the contour of an article is disclosed. Nondestructive viewing techniques including the projection of a light pattern onto the article to be inspected and the imaging of said light pattern to a display screen are discussed. The concepts taught enable the viewing of article regions which were formerly obstructed in conventional viewing systems.

Abstract: A liquid-filled transparent container is spun momentarily to cause the liquid therein to swirl, and successive video frames provide voltage analogs through a television camera. A memory device is synchronized with the camera and stores at least one of the voltage analogs so that a comparator can subtract one successive analog signal from another to generate an error signal if foreign particles are present in the swirling liquid.