Vibration monitoring and control are central topics for machine tools, since high vibration levels reduce the quality of machined surfaces and shorten the tool life. In order to predict potential vibration issues since the early design stage, it is necessary to implement ad hoc numerical models for modal analysis. This requires significant efforts and possible conflicts with tight production scheduling of companies. This work focuses on a specific family of rotary transfer machines for the manufacturing of parts related to lock&keys industry. It investigates the possibility to achieve an acceptable estimation of the elastodynamic behavior of the machine tools through limited modifications of the Finite Element (FE) models used for structural analysis, which are generally available in the early phases of the design process. The structural FE model of a new machine tool is implemented and validated through experimental tests performed on a prototype. Then, the elastodynamic FE model is derived and simulated. The numerical results are consistent with the data provided by Experimental Modal Analysis (EMA). Hence, the proposed approach is confirmed viable and will be integrated in the company workflow of future machine designs.

The damping properties of a commercial polymer concrete are the subject of this application-driven study, which is aimed to investigate the material suitability as a filler of machine bed components to limit vibrations arising in machine tools and automatic machines working at high dynamics. Two main goals are targeted: ( i) quantitative evaluation of the elastodynamic effects due to the polymer concrete insertion into typical components of machine beds, in order to effectively assess its practical potential and ( ii) determination of reliable models of the material, needed to simulate the dynamic response of new design solutions of machines featuring structural components filled with the polymer concrete. The paper is mainly focused on the methodological approach of both the experimental campaign and the signal processing that were carried out. Based on the promising results achieved, the possible use of the polymer concrete as a viable solution to enhance the dynamic behavior of an automatic machine is finally investigated and discussed as a case study.

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