Mémoire de Maîtrise
DOI
10.11606/D.18.2018.tde-11072018-152343
Document
Auteur
Nom complet
Rosana Camargo
Unité de l'USP
Domain de Connaissance
Date de Soutenance
Editeur
São Carlos, 2000
Directeur
Jury
Di Giacomo, Benedito (Président)
Abackerli, Álvaro José
Titre en portugais
Uma metodologia para o cálculo da incerteza das medições a três coordenadas
Mots-clés en portugais
Erro volumétrico
Incerteza de medição
Máquinas de medir a três coordenadas
Resumé en portugais
Titre en anglais
A description of a methodology to calculate the uncertainty measurements to three coordinate
Mots-clés en anglais
Coordinate measuring machine
Error volumetric
Measurement uncertainty
Resumé en anglais
The value of a magnitude is determined through a group of operations that characterize it. The result obtained by these operations is the value of the magnitude, and this value is never the true one because all measurements undergo errors of systematic or random nature, which increase an uncertainty to its result. Thus, all measurement result should include information about its uncertainty, that is, about the interval of values inside of which is considered that the true value is. An international accord, on that subject, allowed the elaboration of the ISO-GUM (Guide for the Expression of the Uncertainty of Measurement), that supplies rules for obtaining the expression of the measurement uncertainty for calibrations, linear dimensional measurements, among others. However, when the task is to estirnate the uncertainty of coordinate measurements, that is, the uncertainty of a point in the space, determined through the indication of a coordinate measuring machine (CMM), the problem is much more complex. Thus, the objective of this work is the description of a methodology to calculate the uncertainty measurements indication of a three coordinate measuring machine. This involves the direct calibration of the machine for the evaluation of the 21 possible geometric errors, the error analysis for defining the equations that allow to estimate the uncertainties of each error individually and the geometric analysis of the machine structure for determining the error synthetization equations Ex, Ey and Ez. The equations that describe the uncertainty of the geometric error measurements were substituted in the uncertainty equations of Ex, Ey and Ez, creating the general equations that allow to determine the uncertainty of the result of a measurement with a CMM.

AVERTISSEMENT - Regarde ce document est soumise à votre acceptation des conditions d'utilisation suivantes:
Ce document est uniquement à des fins privées pour la recherche et l'enseignement. Reproduction à des fins commerciales est interdite. Cette droits couvrent l'ensemble des données sur ce document ainsi que son contenu. Toute utilisation ou de copie de ce document, en totalité ou en partie, doit inclure le nom de l'auteur.
Date de Publication
2018-07-12

AVERTISSEMENT: Apprenez ce que sont des œvres dérivées cliquant ici.
Tous droits de la thèse/dissertation appartiennent aux auteurs
CeTI-SC/STI
Bibliothèque Numérique de Thèses et Mémoires de l'USP. Copyright © 2001-2021. Tous droits réservés.