Metrology

For the past decade, Southern Research has been a leading pioneer in developing precision metrology devices for inspection and characterization of materials for industrial applications as well as space flight qualification of materials and structures. Methods include automated measurements using optical and LASER triangulation-based sensing techniques; many of these methods have been adapted to unusual environments for real-time analysis of the effects of temperature, humidity, and time on materials and structures.

We have developed unique data reduction algorithms for rapid display and analysis of measurement parameters, particularly in the area of shape factors for quantifying deviations from anticipated geometry. Applications for precision metrology include: environmental effects on dimensional stability; thermal effects on dimensional stability; surface contour profiling; and unique or limited access geometry evaluation.

Southern Research offers the following equipment and capabilities in dimensional metrology and shape capture:

• Traditional hand measurement tools (e.g., micrometers, calipers, hole gages)
• 36" digital height gage with 6-1/2 digit measurement capability
• Articulating CMM with laser line probe (LLP)
• Surface mapping with triangulation or confocal lasers - The NDE group at Southern Research has designed and fabricated 3-axis coordinate measurement machines capable of measuring Z height along an X-Y grid. These machines acquire distance measurements using confocal or triangulation lasers and can acquire data on specular or diffuse surfaces. These systems have 2 mil accuracy with sub-micron resolution. This equipment is commonly used to provide surface roughness maps of ablated surfaces, providing valuable information on material loss and ablation patterns. Measurement of defects below the surface has been made on clear materials (e.g., measuring the depth of air bubbles in automobile wind shields).
• Strain field visualization
• Traveling microscope
• Fiber diameters (3 to 25 micron diameters) - Southern Research has designed and fabricated a device to measure small fibers (3 micron to 25 micron diameter) used in the fabrication of carbon composite materials. Diameters are usually measured on samples mounted for mechanical or electrical resistivity testing. The measurement is performed by illuminating the sample with an HeNe laser and recording the resultant diffraction pattern; this pattern is recorded by photodetectors moving along a circular path centered on the sample.
• Extraction of dimensional information from Images and Volumes (e.g., micrographs, CT, radiographs)