Optimal design of dynamic stiffness matching for gear transmission system of mirror horizontal milling machine based on global sensitivity analysis

Mirror structured machine tools are critical equipment for aircraft skin machining, where the dynamic stiffness of the transmission system directly affects machining stability and accuracy. To improve the dynamic performance of thin-walled milling systems, this study proposes a parameter analysis and optimization method based on global sensitivity analysis. First, the coupling relationships among key transmission parameters are analyzed, and a dynamic model of the machine tool transmission system is established. Then, the main parameters influencing dynamic stiffness are identified and classified using global sensitivity analysis. Finally, a mirror horizontal milling machine is taken as a case study, and dynamic simulations are conducted to optimize the sensitive parameters. The results show that the proposed method can effectively identify the key factors governing transmission dynamic stiffness, providing a theoretical basis for improving the control accuracy and machining quality of thin-walled components such as aircraft skins.