## 5 Conclusions
From the results of the tests, it can be concluded that the type of simulated damage had no impact on the determination of the area of its occurrence, and the direction of deviation of the state characteristics was similar in most of the considered cases. Values of the first four natural vibration frequencies of the monitored machine component before and after damage were determined to verify the method. As a result of comparing the determined frequencies, it would be difficult to clearly state that there was damage in the system and to indicate its location in the real machine component. In the future, the authors intend to extend the method by providing qualitative and quantitative data about the damage in a real machine component. It should be mentioned that in addition to the monitoring method formalized in this work, it was also suggested to select the parameters of a discrete system (digital monitoring system) depending on the type of vibrations considered. The parameters of the discrete vibrating system were selected due to the desired dynamic properties in the form of the natural vibration frequency of the monitored machine component and the law of conservation of mass. As a result of the synthesis, a set of six solutions was obtained that met the desired properties of the sought discrete system, of which one was selected which was closest to the RFE (rigid finite element) method. In the future, the authors plan the tests aimed at selecting the optimal tuning of CSM parameters due to the sensitivity of the method for monitoring real machine components formulated in this work. The suggested task of synthesizing the discrete vibrating systems with respect to the desired dynamic properties and mass distribution may contribute to the development of a new approach to creating a discrete model corresponding to real systems and their physical properties. The application of the developed method to monitoring real machine elements will require the representation of the real load in a digital diagnostic system. Although machines often operate in predictable conditions in terms of the nature and value of the load, an important research issue in this context should be to conduct research to determine the sensitivity of the proposed method to changes in the load value, structure and parameters of the digital diagnostic model. Another problem to be solved in the case of using this method to monitor real machine elements is the selection of appropriate sensors in terms of their operating conditions, installation method and data acquisition. Conceptualization: A.D., T.D., K.H. and P.O. ; methodology: A.D., T.D., K.H. and K.S. ; software: T.D. and K.H. ; validation: A.D. and K.B. ; formal analysis: Z.M. and C.G. ; investigation, K.H. ; resources: P.O. and K.B. ; data curation: A.D. and T.D. ; writing--original draft preparation: A.D. and K.H. ; writing--review and editing: K.B. and Z.M. ; visualization: K.H. and K.S. ; supervision, A.D. and C.G. ; project administration: C.G. All authors have read and agreed to the published version of the manuscript. This research received no external funding. Not applicable. The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding author. The authors declare no conflict of interest.