Cylindrical surface irregularities presented by frequency spectra of relative tool displacement to the workpiece

The paper presents the frequency components of turned surface irregularities. Due to the wide-band character of the surface irregularities being difficult to analyse by normative parameters, they were analysed in the amplitude–frequency domain based on fast Fourier transformation. This approach to the presentation of an irregularity signal, which has a stationary and ergodic character, is required both in the practical detection of surface irregularities and academic research. This measurement method utilises a machining datum surface and can be used to diagnose the disturbances of a surface geometrical structure. The formation of longitudinal irregularities for the turning process has been presented. An original system for the measurement of longitudinal irregularity of relative tool displacement to the workpiece has been proposed. To generate transverse irregularity profiles, a procedure of hybrid synthesis of measured relative tool displacements to the workpiece with the theoretical outline of the cutting edge has been performed. This practical approach to measurement of tool-to-workpiece displacement combined with a theoretical definition of tool profile, constitutes a novel and significant contribution to further diagnostic surface studies. An original description in the amplitude–frequency domain and a common formulation of transverse and longitudinal irregularity is presented, having greater research and diagnostic capabilities than stereometric surface diagrams. Spectral characterisation of cylindrical surface disturbances presents a more advanced analytical approach than a conventional narrow-band filtered method of measuring surface irregularities. The proposed method creates a base for a new surface measurement system, which includes the disturbances of the surface created in the machining process.