Aiming at the stiffness optimization key problems of machine tools

due to insufficient analysis of numerical iterative optimization algorithm and high cost of optimization machining test caused by complex structure and large size of machine tool

this paper provided the method of combining finite element modal analysis and experimental modal analysis to optimize the dynamic stiffness of machine tools including the vertical and gantry boring-milling CNC machine tools. Combined with the modal test analysis and FEM

the results show that without considering the stiffness and damping of moving pairs of machine tools

the simplified FEM modal analysis of the machine tool could better reveal the dynamic characteristics of the machine tool structure. According to the weak area of the dynamic stiffness of the structure

the low-order frequencies of the machine tools are increased by more than 10% and 40% respectively. Importantly

it is showed that the optimization analysis method could be applied to the analysis process of structural general optimization design.