Banca de DEFESA: PEDRO VINÍCIUS FERNANDES DE ANDRADE

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : PEDRO VINÍCIUS FERNANDES DE ANDRADE
DATE: 03/06/2022
TIME: 09:00
LOCAL: Sala 207 do Complexo de Pós-Graduação do Centro de Tecnologia (PGTEC)
TITLE:

Uncertainty Evaluation in a Coordinate Measuring Machine for a Glossmeter.

KEY WORDS:

Uncertainty, gloss measurement, optical geometry, coordinate measuring machine.

PAGES: 89
BIG AREA: Engenharias
AREA: Engenharia Mecânica
SUBÁREA: Projetos de Máquinas
SPECIALTY: Fundamentos Gerais de Projetos das Máquinas
SUMMARY:

The present study sought to operationalize a coordinate measuring machine for a glossmeter produced in laboratory, including an evaluation of the uncertainties associated with the positioning of the glossmeter, so that it can be used in future scientific research. A typical application to be considered is obtaining the spatial distribution of gloss over porcelain ceramic tiles, where the level of surface finishing is the main quality criterion of polished products. Therefore, the study began with the operation of the coordinate table, which was inoperative due to problems of communication between the motors and the controller board, in addition to the need of configuration of the control software. The machine became functional by adjusting the electronic connections that communicates between the board and the drivers and by reconfiguring the control software. As for uncertainty assessments, the methods established by the ISO-GUM guide were applied. The positioning system consists of a stepper motor machine with toothed belt transmission. Simulations were performed considering positioning error as the main source of uncertainty, once each measurement cycle ends, the sensor is repositioned, and the effective measurement area of the device ends up being slightly altered. The orthogonal components, X and Y, of the machine's work plane, were assumed to be coincident with the polished surface of the ceramic plates, and both as components of the positioning error. For each axis, the positioning error was estimated in 31 regularly spaced positions, adopting a random order in the measurement sequence. The reference position for calculating the positioning error was obtained using a linear precision scale. Eight replications were performed at each position. Considering that, for the sake of saving test time, gloss measurements are usually made with sequential (non-random) positions, a series of position measurements were also performed at sequential positions, for comparison purposes. In addition to the uncertainties 7 obtained for each position, a systematic error of positioning was identified, in both axes, attributed to the transmission system (stepper motor with toothed belts). Such results allow that other studies carried out with the machine can be validated.

BANKING MEMBERS:
Presidente - 2266607 - FABIO JOSE PINHEIRO SOUSA
Interno - 1792669 - ADILSON JOSÉ DE OLIVEIRA
Externo ao Programa - 1943220 - ORIVALDO VIEIRA DE SANTANA JUNIOR
Externo à Instituição - WALTER LINK