Laser surface scan accuracy tested

This is encouraging for those of us who rely upon 3D surface data collected with laser scanners: “Dimensional accuracy and repeatability of the NextEngine laser scanner for use in osteology and forensic anthropology”.

Second, as an application to osteology we examined intra-observer scanning protocol variability, using the coefficient of variation (CV) to quantify surface area and volume variance between repeated scans of eight porcine capital femoral epiphyses with undulating mammillary processes on one surface with amplitudes covering the range of the test block bas-relief offset values. The CoR showed each test-retest measurement from each instrument differed by no more than their CoR: 0.010 mm, 0.137 mm, 0.068 mm, 0.193 mm for the VHX, NE, HP and CMM, respectively. There was agreement between the instruments, but each instrument (NE, HP and CMM) overestimated bas-relief features as reported by the VHX, on average (bias) by 0.046 ± 0.038 mm, 0.025 ± 0.033 mm, 0.026 ± 0.033 mm for the NE, HP and CMM, respectively. Both scanners captured surface features as small as 0.1 m

Porcine capital femoral epiphyses – that’s a pretty great test of some of the small bone fragments that we study in the fossil record. Errors of less than 0.1 mm are less than I would have expected.

The research is by Ronald Perrone, Jr. and John L. Williams in Journal of Archaeological Science: Reports.