Problems of Selecting the Wavelet Transform Parameters in the Aspect of Surface Texture Analysis

This paper discusses one of the most important problems related to analysis of surface texture using wavelet analysis - the problem of selection of mother wavelet and decomposition level. The literature related to wavelet transform does not explicitly determine which mother wavelet is most suitable for surface profile analysis and at which level of decomposition this analysis should be performed. The paper describes the criteria of selection of the mother wavelet from the aspect of analysis of two-dimensional surface texture. Details of the algorithms are also included. The calculations were performed on the 3D roughness profiles. The evaluation was based on five selection criteria: autocorrelation test, Pearson correlation, evaluation of 3D roughness parameters, Hotelling test and entropy-based method. The calculations were performed in authorial computer procedures coded in MATLAB software

The Study of the Influence of the Tracing Speed on the Result of Surface Roughness Measurement Using the Tactile Method

This work concerns the problem of measuring surface roughness using the tactile method. The result of such a measurement is influenced by many factors, for example, the applied measurement parameters or changes in ambient conditions, e.g., temperature. The authors attempted to determine the influence of the tracing speed of the result of the profilometer tip on the roughness measurement of surfaces characterized by different types of irregularities. In the experiment, samples manufactured using various machining techniques were measured. Eleven selected roughness parameters were observed, including the most well-known ones, such as Ra, Rz, or Rt. The results obtained by the authors allowed them to determine which of the analyzed parameters are the most sensitive to changes in the tracing speed of the measuring tip, which is of great importance in the aspect of surface roughness measurements in industrial conditions. Owing to the obtained results, it is possible to determine in which cases it is possible to increase the speed of tip travel without reducing the reliability of the obtained results of surface roughness measurement

An assessment of applicability of the two-dimensional wavelet transform to assess the minimum chip thickness determination accuracy

The objective of the study was to assess the potential use of optical measuring instruments to determine the minimum chip thickness in face milling. Images of scanned surfaces were analyzed using mother wavelets. Filtration of optical signals helped identify the characteristic zones observed on the workpiece surface at the beginning of the cutting process. The measurement data were analyzed statistically. The results were then used to estimate how accurate each measuring system was to determine the minimum uncut chip thickness. Also, experimental verification was carried out for each mother wavelet to assess their suitability for analyzing surface images

METROLOGY AND MEASUREMENT SYSTEMS STATISTICAL VALIDATION OF THE METHOD FOR MEASURING RADIUS VARIATIONS OF COMPONENTS ON THE MACHINE TOOL

Abstract This paper deals with the experimental validation of the suitability of the method for measuring radial variations of components on the process tool. The tests were conducted using a computerized PSA6, which was compared to a Talyrond 73. The results of measurement of roundness deviations as well as roundness profiles were analyzed for a sample of 70 shafts. The roundness deviations were assessed by determining the experimental errors, while the profiles obtained with the tested device were compared to those registered by the reference device using three correlation coefficients