Methods for modal parameters identification applied to CNC machine tool feed drives

The paper presents a critical appraisal of existing methods for the identification of modal parameters (natural frequencies, damping ratios and mode shapes) for CNC machine tool feed drives. The classical methods for modal parameter identification are briefly discussed and the advantages of novel application of Continuous Wavelet Transform for modal parameter identification of CNC machine tools are underlined.
The evaluation of the state of the art of modal analysis techniques also contains a description of the main methods used in the modern experimental modal analysis applied to frequency and time domains. The accuracy of modal parameters (especially of damping ratios) identified from the measured frequency response function is influenced by various parameters and conditions, depending on which modal parameter extraction technique is used.
The conclusions of the critical appraisal of these methods will help the designers and academic and industrial researchers to develop and use methods which permit the calculation of modal parameters with high accuracy