Evaluation of workpiece roundness error in a turning operation: An assessment of computational algorithms by using simulated data

Circular or cylindrical features are fundamental geometric features in quality control of manufacturing products. At present, the standard for geometric dimensioning and tolerancing specifies a circularity tolerance based on the tolerance zones defined by two concentric circular boundaries. The purpose of our research is to investigate the effect of measurement error resulting on the form tolerance estimation, obtained by some form fitting algorithms. This paper presents a study for roundness tolerance modelling and analysis, as well as a software tool for assessing the implemented fitting algorithms. To represent profile variations within the tolerance zones, a simulation tool, which is based on a harmonic roundness model using Fourier series expansions, has been used. The simulation tool has been implemented within the Matlab environment and includes both the least square and minimum zone tolerance fitting algorithms.