Uncertainty analysis of point-by-point sampling complex surfaces using touch probe CMMs: DOE for complex surfaces verification with CMM

The paper describes a study concerning point-by-point sampling of complex surfaces using tactile CMMs. A four factor, two level completely randomized factorial experiment was carried out, involving measurements on a complex surface configuration item comprising a sphere, a cylinder and a cone, combined in a single assembly. An investigation into the source and effects of different uncertainty contributors during this complex surface measurement was carried out. The factors involved were machine, probe, operator, and procedure dependent. The results obtained from the experiments were analysed in terms of deviations from CAD model, reproducibility, and measurement uncertainty. Statistical analysis and uncertainty budget are presented.