ANSYS supports three contact methods: a point 2 point contact unit, a point 2 surface contact unit, and a surface 2 surface contact unit. The contact element method needs to set the contact stiffness. The contact stiffness is obtained by K=αPβ, where K is the contact stiffness, α and β are the joint surface characteristic parameters, and P is the contact surface pressure. The stiffness damping spring method uses a series of springs and dampers to form a spring unit between two substructures. The series of spring units form a dynamic model of the joint surface. The dynamic parameters of the model are the spring elements. Spring stiffness and damping. This is a relatively mature method of joint analysis. Generally, the contact element method is used for the finite element analysis of the sliding guide machine tool considering the guide rail parameters, and the stiffness damping spring method is adopted for the finite element analysis of the machine tool using the linear rolling guide. In this paper, the stiffness damping spring method is used, and the dynamic model of the linear rolling guide is shown. The finite element analysis model includes the bed, the guide rails, the saddle, and the small slide section, and the finite element model is shown. The unit for simulating stiffness and damping selects the COMBINE14 spring unit. The real constants defining the normal COMBINE14 unit are: stiffness: 298N/μm, damping: 1063Ns/m; the real constant defining the tangential COMBINE14 element is: stiffness: 235N/μm, damping: 1084Ns/m. with ANSYS After the program is solved, the natural frequency of the machine tool is obtained, the first order is 1311132Hz, the second order is 18815501Hz, and the third order is 2011217Hz. Dynamic model of linear rolling guide Linear guide rail finite element model 212 Harmonic response analysis In harmonic response analysis, it is performed twice. One is the harmonic response analysis of the X-direction excitation, and the other is the harmonic response analysis of the Z-direction excitation. In the X-harmonic response analysis, the analysis frequency is selected around 690Hz, the normal spring stiffness is: 2126E7N/m, the damping is: 1063Ns/m, the excitation point is at the center of the small slide, and the pick-up point is close to the guide rail. At the block; in the Z-harmonic response analysis, the analysis frequency is selected around 530 Hz, the tangential spring dynamic stiffness is: 71252E6N/m, the damping is: 1084Ns/m, the excitation point is at the left center of the small slide, and the pick-up point Close the slider on the rail. After solving with the ANSYS program, the harmonic response analysis results are shown. The finite element analysis of the joint surface characteristics of the machine tool rail was carried out by ANSYS. The analysis process took into account the parameters of the rolling guide joint surface. Compared with the machine vibration test, the analysis results were more accurate. The static stiffness of the joint surface can be obtained by static stiffness experiments, and the dynamic stiffness and damping can be identified from the modal experiments. The dynamic characteristic analysis method based on the finite element method of the machine tool rail joint surface parameters enables the designer and the harmonic response analysis result to know the dynamic characteristics of the machine tool in the design stage, and make it possible to predict the whole machine characteristics. (Finish) weihaimaideqi , https://www.weihaimaideqi.com