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In the milling process, the spindle vibration response is an important factor affecting the machining quality and accuracy. In this article, the mechanism of cutting vibration coupling is analyzed, and the dynamic cutting thickness during the milling process is calculated to make the model more accurate and closer to the actual situation. The five degrees of freedom nonlinear vibration model is established to analyze the instantaneous dynamic behaviour under cutting force and unbalanced mass excitation. The linear stiffness and bearing contact force models of the spindle system are derived by Hertz's contact theory. On the basis of the established simulation model, the effects of unbalanced mass eccentricity, spindle speed, axial preload, milling condition parameters on the dynamic behavior are analyzed. The feasibility of the coupled dynamic model is confirmed through experiments. The motion behaviour of the spindle exhibits rich and complex non-linear phenomena due to the interaction of cutting force and vibration response. Therefore, the proposed model provides a theoretical basis for the prediction of cutting force and dynamic characterisatic during the milling process. [ABSTRACT FROM AUTHOR]

The sliding guide plays a crucial role in CNC (Computerized Numerical Control) machine tools, as its dynamic characteristics can significantly impact the machining quality and reliability. Therefore, this study focuses on the analytical modeling and analysis of the sliding guide system. Firstly, a static model of the sliding guide system is established based on fractal theory. The accuracy of the static model is verified through loading experiments. Utilizing the developed model, the influence of relevant parameters on the bond surface stiffness is analyzed. Subsequently, the concentrated mass method is applied to further develop a nonlinear dynamics model of the system based on the static model. The nonlinear dynamical equation is solved using the Runge–Kutta method. The vibration responses at various excitation frequencies are measured and compared with simulation results, which show good agreement. Lastly, based on the established dynamic model, the study investigates the effects of parameters such as external load, sliding guide material, excitation frequency, tilting surface angle, and slider mass on the dynamic characteristics of the sliding guide system. The main result of this research is to establish the static model of wedge sliding guide based on fractal theory, and further establish the dynamic model of wedge sliding guide on this basis. On the basis of the dynamic model, relevant parameters are discussed, and the effects of different parameters on the dynamic characteristics of the sliding guideway are obtained through the parameter discussion. Based on the results of parametric discussion, the performance of sliding guide can be enhanced by changing the parameters. This study helps to prevent resonance and instability in sliding guide systems. By investigating the analysis and modeling of the sliding guide system, this study aims to enhance the understanding of its dynamic behavior and improve the overall performance of CNC machine tools. [ABSTRACT FROM AUTHOR]