Most roundness measuring systems which find automatically the “reference circles” to a profile have used, for convenience,a limacon figure as an approximation to a circle. However this figure has important geometrical properties relevant tonormal roundness measurement and can be regarded as the basis of an analytical system rather than an instrumentalconvenience. This paper examines some…
Abstract An instrument has been developed which can measure not only radius of curvature but also form deviation and surface texture at the same time. A computer is used to mathematically separate the form from the texture. The technique can be applied to the measurement of cross track curvature of bearing raceways and to other…
AbstractSome applications in the field of surface metrology are described for a new stylus instrument incorporating a transducer with a wide dynamic range.The transducer has a range of 2.0 mm and a resolution of 5 nm enabling the measurement of both the fine surface texture and the surface form of ahighly formed component to be…
AbstractIn stylus measurements of surface texture the measured results for roughness depend on the stylus radius. Therefore it is important to determine the stylus radius. Since stylus tips are not perfectly spherical, the local radius of curvature varies significantly over the surface which makes thedetermination of an effective radius difficult. Both the techniques used to…
Abstract An appraisal is given of the qualities of diamond styli which are used for surface texture measurement. Some of the difficulties encountered in normal optical and electron optical methods of assessment are discussed, and a possible solution which involves a two-stage replica process isdescribed.
Early developments of stylus instrument for surface profile measurements are documented in this paper. R.E reason is the father of M system/Mean line system for surface profile analysis
Surface-measuring instruments and the factors limiting their performance are studied. For comparison between instruments, the ability to measure sinusoidal perturbations of varying amplitude or wavelength can be used.
Abstract Engineering surfaces are comprised of a range of spatial wavelengths. Filtering techniques are commonly adopted to separate the different wavelength components into well-defined bandwidths. Filtering is done prior to numerical characterization and it is also essential for extracting information needed to provide process feedback and establish functional correlation. This paper reviews commonly used filters…
A new approach to roughness filtering is described using digital filters designed and simulated in a general purpose computer. The filters were used to process the digitized surface profiles and the performance is compared with that of available analogue filters.
An essential preliminary to numerical assessment of roughness is the elimination of waviness. The waviness is usually filtered using analog filters of the capacitance-resistance type. This paper deals with a digital technique to remove the waviness. FFT, one of the important tools of digital signal processing was used to filter surface profiles. This technique was…
This paper deals with the application of finite Fourier series to analyse the surface profiles. A good approximation could be obtained using only a fraction of the maximum number of harmonics. The criteria to fix the fraction is dealt with in detail and this will enable us to find out the optimal degree to which…
The principal developments in the stylus measurement of roughness texture are traced. The instrument problems which were encountered, particularly with regard to the requirements of transmission characteristics and reference lines, are outlined. The behaviour of the skid is given further consideration, and a distinction is drawn between the systematic error resulting from its application to…
