UAME size being defined as opposing points (if I were to use ISO standard), how does PC-DMIS handle estimating the missing point, in cases where an odd number of hits are used? Is it sampling only the 2 points adjacent to the missing hit?
What happens in an extreme case? Let's assume the diameter being measured is actually an isosceles triangle, the operator took only 3 hits, and just happened to clock those hits in worst possible way?
UAME size is not using opposed points, it is the Unrelated Actual Mating Envelope which for ISO is a constrained MIN/MAX, external to material fit. Opposing points applies to Local Size.
If you only take three points, PC-DMIS will calculate a perfect circle (no form error) and the UAME and Local Size will be identical. Once you take more than the minimum number of hits required to mathematically calculate a feature you will start to see form deviation. When calculating local size using the opposed points method, we interpolate.