Differences in Roughness Parameter Values from Skid and Skidless Contact Stylus Profilometers

Abstract

Contact stylus profilometry is the leading surface texture measuring method in many manufacturing industries. For years it has been unmatched in terms of accuracy and reliability. Advancements in technology have led to the improvements in the profilometer design. A stylus can either have a built in skid or be skidless. In this study, the influence of skid on the measurement accuracy and repeatability was evaluated. Four different contact stylus profilometers were used to measure three standard roughness artifacts each. Every set of measurements consisted of 50 repetitions of the same profile, with the same parameters. Out of these profiles, five roughness parameters were calculated and were subjected to a statistical analysis. Relative errors of these parameters were also considered and presented individually for each roughness standard. Researchers found differences in the measurement results dispersion of various roughness parameters between the three roughness standards. The presented results of the measurements clearly indicated that there is a dispersion of the obtained values for the older type of contact stylus profilometer (P1, skid). The skidless portable devices, P2 and P3, have better measurement resolution, which results in a noticeably lower dispersion of measured values. A tabletop, stationary device utilizes a skidless measuring probe. It has both the best resolution and the highest rigidity, which results in the lowest dispersion of measured values. The lowest relative error of the Ra parameter was determined for the P2 device (9.2%) and the highest was determined for the P3 device (72.6%).

Quality Assessment of a Novel Camera-Based Measurement System for Roughness Determination of Concrete Surfaces—Accuracy Evaluation and Validation

“…Nevertheless, the difference between new and old styli was more severe, being as much as 20% for primary profiles and about 5% for roughness profiles. Additionally, Grochalski et al examined the scattering of roughness parameters based on four different stylus profilometers, two of them with a skid and the other two skidless [13]. The experiments revealed that there is a considerable difference between styli with skid and skidless ones, while the skidless ones had a better resolution leading to lower scattering of measured values.…”

Estimation of Surface Roughness on Milled Surface Using Capacitance Sensor Based Micro Gantry System through Single-Shot Approach

“…Methods to measure surface roughness parameters are broadly classified into contact and noncontact types. For offline measurement, well-established contact-type method such as the stylus profilometer method were used [ 8 ], and noncontact methods using optical techniques such as vertical scanning interferometry (VSI) and the confocal method were preferred for profile measurement as well as areal surface roughness measurement [ 9 ]. However, the stylus method has limitations such as the need to change the tip of the stylus for different roughness ranges, as contact over the surface will cause damage to the machined specimen and the stylus itself, and for single probing optical methods such as VSI and confocal methods, standard laboratory conditions for measurement are required, which limits the ability to use these methods in online conditions.…”