Bilateral comparison on micro-CMM artefacts

Project Description

In this cooperation, comparison measurements will be made on 3 selected test objects for micro-CMMs provided by PTB. The cooperation leads to information on suitable artefacts and practical issues for handling and measurement strategies. This work will be helpful for future comparisons in the new field of micro-CMM calibration.

Final Report 2012-03-21

The project has been completed and the report can be downloaded here>>

Within this EURAMET project suitable artefacts for micro-CMM performance comparisons were identified, measurement strategies were studied and first comparison measurements were performed.
The three test objects selected were a Zerodur hemisphere plate (Zeiss), a ø1 mm cylindrical gauge (Cary) and a 1 mm ruby shere (SWIP). The Zerodur hemisphere plate is a newly developed standard for micro-CMM verification. It was stable within a few nm and therefore very well suited for low uncertainty micro-CMM comparisons. Of course also the ruby sphere with a very low form deviation was well suited and stable, however, the relative large form deviation of the cylindrical gauge made it much less useflull for comparisons.
The results obtained on the hemisphere plate indicate that both laboratories agree well within the small stated standard uncertainties of roughly 25 nm. This very good agreement highlights the high quality of the micro-CMMs used and the advanced degree of theire calibration and validation.

This was the first comparison within EURAMET in the field of micro-coordinate measurement techniques and it was of great benefit for the participants.