Improvement of segmented bars for the verification of coordinate measuring arms

Evaluation of 3D measurement uncertainties in a shop floor for any measurands

Virtual machine concept applied to uncertainties estimation in instrumented indentation testing

The basis of the virtual machine concept, which is commonly used in coordinate measuring machines, was implemented to determine more realistic uncertainties on the estimation of the elastic modulus obtained from nanoindentation tests. The methodology is based on a mathematical model applied to simulate the testing process and to evaluate the uncertainties through Monte Carlo simulations whose application depends on the studied system (instrument, material, scale, etc.). The methodology was applied to the study of fused silica (FQ) and steel samples tested in a nanoindentation system. The results revealed that the most relevant sources of uncertainty are related to the calibration procedure,…

Optimization of the straightness measurements on rough surfaces by Monte Carlo simulation

Summary The straightness error of a coordinate measuring machine (CMM) is determined by measuring a rule standard. Thanks to a reversal technique, the straightness uncertainty of the CMM is theoretically dissociated from the straightness uncertainty of the rule. However, stochastic variations of the whole measurement system involve uncertainties of the CMM straightness error. To quantify these uncertainties, different sources of stochastic variations are listed with their associated probability density functions. Then Monte Carlo methods are performed first to quantify error and secondly to optimize measurement protocol. It is shown that a 5-measurement distance from 0.1 mm to each measurem…

Rapid and robust on-site evaluation of articulated arm coordinate measuring machine performance

International audience

Etalonnage et incertitudes associées de cuves refroidisseurs de lait en vrac de grande capacité

Dans le vocabulaire international de metrologie (edition 2008) [1], la definition de l'etalonnage aevolue. Il y a maintenant deux phases, la premiere est toujours d’etablir la relation entre les valeurs et lesincertitudes de mesure associees fournies par des etalons et les indications correspondantes avec lesincertitudes associees. La deuxieme phase est l’utilisation de cette information pour etablir une relationpermetant d’obtenir le resultat de mesure a partir de l'indication. Ce travail s'inscrit dans le cadre del'amelioration de la qualite et de la tracabilite des reservoirs de grande capacite fabriques par la societe Nevinox(groupe Galactea) a Nevers (France). Le but du papier est de d…