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Bartosz Gapinski, Miroslaw Grzelka, Miroslaw Rucki
THE ACCURACY ANALYSIS OF THE ROUNDNESS MEASUREMENT WITH COORDINATE MEASURING MACHINES

In the article, the form deviation (roundness) measurement with the Coordinate Measuring Machine has been discussed. The influence of the measuring points number and the type of the roundness deviation on the result (since different fitting elements are used) has been presented. The obtained investigation results prove that minimal number of points is not enough for measurement, while the too large number does not improve the measurement, as well. The recommendation on the measuring points number have been given.

B. Dhanasekar, B. Ramamoorthy
SURFACE ROUGHNESS EVALUATION OF CYLINDRICAL MACHINED SURFCAES

Computer vision based on digital image processing is a fast emerging as a research tool in various branches of engineering. In manufacturing engineering environment it is mainly used for robot applications like inspection, recognition and navigation. In this work the area of application is extended to incorporate its use in metrological applications where the objective of the work had been to evaluate the surface roughness of cylindrical machined surface (turned) using machine vision technique. Basically to estimate the roughness of a cylindrical surface based on the images would pose a fundamental problem as the surface being a doubly curved one. This image distortion need to be resolved before proceeding to the evaluation of roughness of such surfaces. This study uses involved the geometric correction technique by developing an algorithm in which distortion encountered in the projection of cylindrical machined surface image is rectified. The quantification for surface roughness after opening the surfaces is performed using the surface image parameters (spatial frequency (F), arithmetic mean value (Ga) and standard deviation (STD)). Then the Group Method of Data Handling (GMDH) technique was used to obtain an analytical relationship of the roughness parameters calculated using the digital surface image and the stylus instrument values. An analysis based on the comparison to make sure that the present approach of estimation of surface finish based on the digital processed image could be implemented in practice, is presented in this paper.

Saulius Kaušinis, Aurimas Jakštas, Rimantas Barauskas, Albinas Kasparaitis
INVESTIGATION OF DYMANIC PROPERTIES OF LINE SCALE CALIBRATION SYSTEMS

The paper addresses the error-related problems specific to line scale calibration in dynamic mode of operation that are caused primarily by geometrical and thermal deviations of the calibration system components. A new 3D finite element model has been developed in order to both investigate thermo-mechanical processes in the comparator structure and evaluate possible temperature influence on geometrical dimensions of the line scale. An interferometer-controlled comparator setup with a moving microscope has been designed to evaluate the performance of the long scale calibration process.

Ilknur Cavusoglu, M.Numan Durakbasa, P. Herbert Osanna
PROCESS PERFORMANCE EVALUATION AND IMPROVEMENT FOR THE QUALITY PROGRESS IN THE INDUSTRIAL MANUFACTURING SYSTEMS

As the competition gets tougher, there is more pressure on manufacturing sectors to improve quality and customer satisfaction while decreasing cost and increasing productivity. These can be achieved by using modern quality management systems and process improvement techniques to reduce the process variability and driven waste within manufacturing process using effective application of statistical tools. There are a number of different methods for collecting and evaluation data. One of them is pre-control. Pre-control is a technique that helps shop operators to control the process so that defective parts are not produced. This technique is also simple to understand for the shop operators and statistically robust. In this study, it was used this techniques for the quality progress of the production parts with one-sided geometrical tolerances.

Stanislaw Adamczak,Dariusz Janecki, Krzysztof Stepien
AN ANALYSIS OF ERRORS OF V-BLOCK CYLINDRICITY MEASUREMENT WITH REGARD TO THE METHOD PARAMETERS

At the Kielce University of Technology (PL) a new method of cylindricity measurements using V-blocks has been developed. Results of the statistical verification of the method show that its accuracy equals about 19% in relation to accurate radial method. The paper presents results of the research work covering the analysis of potential sources of errors of the method, related to the method parameters.

Petri Österberg, Heimo Ihalainen, Risto Ritala
MEASUREMENT OF WOOD QUALITY PARAMETERS FROM ANNUAL RINGS USING COLOR ANALYSIS WITH DIGITAL IMAGES

In this paper we present an image analysis method which provides wood quality parameters from board and log end images. Our analysis recognizes annual rings in prepared cutting surface despite of varying color pattern or lighting. After locating annual rings accurately, proportions of earlywood and latewood can be measured globally and locally in the image. Our method is based on combining moving window to principle component analysis (PCA). Furthermore, we apply various filtering methods to enhance result matrixes.

Andrej Predin, Ignacijo Biluš, Mitja Kastrevc, Roman Klasinc
MEASURING SYSTEM FOR RIVER BED AND WATER SURFACE MAPPING

This contribution presents a measuring system model (up to 5 m crossing distance) for river bed and water surface mapping. The basic parameters of the system are given together with principles of driving/controlling and measuring data processing.

Jean Mailhé, Jean-Marc Linares, Jean-Michel Sprauel
VERIFICATION BY VIRTUAL GAUGE USING A STATISTICAL CRITERION

For the most part, metrology software is currently based on the measurement of distances or angles between geometrical elements. If this method of verification is well adapted to geometrical specification without a virtual state modifier, this is not appropriate for specification based on envelop zone such as in maximal matter condition, for example, for the ISO2692 standard. Usually the least squares best fit method is used to estimate derived surfaces, but the statistical information contained in the acquired coordinates remains under-used. The aim of this paper is to present a new approach for the verification of a part, based on a virtual gauge and using a statistical criterion.

Alexandre Titov, Igor Malinovsky
HIGH-PRECISION TEMPERATURE MEASUREMENTS OF MATERIAL ARTIFACTS

Important advances in temperature measurements of material artifacts are reported as a result of a new approach in high-precision calibration of thermometers, which is free from contribution of temperature gradients in the calibration system and velocity error, associated with time delays due to propagation of heat waves in artifacts.

Han-Young Ryu, Won-Kyu Lee, Han-Seb Moon, Chu-Shik Kang, Ho-Suhng Suh
A NOVEL DILATOMETER FOR MEASURING COEFFICIENT OF THERMAL EXPANSION OF ULE-MATERIAL USING A FIBER RING LASER

A new type of measuring system for coefficient of linear thermal expansion (CTE) of ULE (Ultra Low Expansion) material by using a fiber ring laser is introduced in this paper. The lasing frequency of the laser is stabilized to one of the transmission peaks of the etalon filter by controlling the resonant frequency of the tunable filter. The spacer of the (Fabry-Perot type) etalon filter is made of ULE material.
We could measure the CTE of ULE by measuring the optical frequency change caused by the temperature change of the etalon spacer. The combined standard uncertainty is estimated as the value of 3.66 · 10-8.

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