Improvement of Measurement Accuracy of Optical 3D Scanners by Discrete Systematic Error Estimation

Abstract

A new methodology is introduced which enables the improvement of measurement accuracy of optical 3D scanners. This improvement is based on geometric compensation of the systematic measurement error over the measurement volume. Possible sources for systematic measurement errors are introduced and discussed. Estimation of the systematic error is performed by determination of length measurement error of a ballbar in different positions in the measurement volume. Description of the systematic error may be done using polynomials or sampling points in an equidistant volumetric grid. Simulations as well as experimental measurements using real data were performed in order to evaluate the new methodology. The results show that a reduction of the systematic error to about half of the original error is possible. The method is discussed, and potential improvements are given as prospective future work.