3D Laser Scanners For the Win!

It’s no surprise that tiny precision objects, such as the parts inside your smartphone, must be measured with laser technology in order to fit together and work properly. But some of the largest structures people depend on every day -- including airplane wings and bridge components -- are also measured to exacting standards by three-dimensional laser scanners.

Despite the importance of such measurements, however, there is no comprehensive standard or agreed-upon suite of tests to judge how well those 3D instruments perform – although the American Society for Testing and Materials International (ASTM) has been working for years on a draft standard.

That’s why PML scientists recently designed and built a calibration facility specifically set up for conducting the approximately 100 proposed tests in the ASTM draft standard. Then they invited all the leading 3D scanner manufacturers to perform measurements in a head-to-head runoff. In May of 2016, major manufacturers from around the world converged at NIST to put their scanners through the paces.

That showdown not only revealed differences among different manufacturers when measuring exactly the same structures, but provided new perspectives on testing, leading to a revision of the draft standard. That document is in the process of being voted on, and researchers from PML’s Dimensional Metrology Group expect the revised version to be adopted by the end of 2017.

"If someone in an organization wants to know which scanner to buy, he or she will look at the specs," said one runoff participant. And with an official standard for 3D laser scanner performance, “the specs will mean the same thing because they were tested against the same type of standards and the same type of objects.”

Think about that the next time you’re driving over a bridge or looking out an airplane window.