Measurement for True Surface Analysis : Modern Machine Shop

Optical metrology is providing more information, faster, about surfaces that were once impossible to measure and understand. When an engineer includes a surface finish specification on a print, the intent is usually not just for aesthetics. Surface finish affects how a part will fit, wear, reflect light, transmit heat, distribute lubrication and accept coatings. The finish should be determined by the part’s function: A surface should fulfill the engineering requirements of the application without wasting time and effort on a higher quality finish than necessary. In fact, many applications do better with a certain amount of “texture,” and too fine of a finish can be just as bad as too coarse of a finish. In the 1940s, the surface finish measurement upgraded from visually comparing patch reference standards to moving a fine stylus across a part’s surface via a transducer and amplifier. This provided part measurement data that could be recorded and analyzed against various surface parameters to evaluate its roughness, profile and waviness. For the next half century, this technique was invaluable to various industries: It helped engines last longer, improved fuel e...

A 3D model of the skeletal muscles responsible for bird flight provides the most comprehensive and

A 3D model of the skeletal muscles responsible for bird flight provides the most comprehensive and detailed picture of anatomy to date, researchers say. The study will form the basis of future research on the European starling’s wishbone, which these particular muscles support. Scientists hypothesize the wishbone bends during flight. “A lot of people have looked at this on a larger scale, but not in the detail we acquired,” says Spiro Sullivan, a doctoral student in the School of Medicine at the University of Missouri and lead researcher of the study, which appears in Integrative Organismal Biology: A Journal of the Society for Integrative and Comparative Biology. “It’s an unprecedented look into an especially tiny animal that bridges the gap between microscopic and large-scale muscle function.” The researchers used an Xradia X-ray microscope to collect the data and create a three-dimensional model of the bird’s muscle fibers. “We’re using a mixture of enhanced CT imaging scans in combination with this new visualization technique of 3D muscle fiber architecture,” says Casey Holliday, an associate professor in the School of Medicine. “It’s one of the first biological uses of thi...