Numerical sensitivity analysis and design optimization of structural dynamics for a 5-axis milling machine

Sensitivity analysis is a powerful tool to help the engineer determine the interactions in system and identify the key parameters. This paper presents an approach of numerical sensitivity analysis for the optimization of structural dynamics of a 5-axis milling machine. Meta-model for the structural dynamics of the main axis assembly is estimated by use of a DOptimal design. Global sensitivity analysis is performed for the tool vibrations and the key design parameters for the improvement of the machining dynamics are identified. A comparison between a design modification based on the results of sensitivity analysis and a design optimization by means of genetic algorithm will also be presented. As a result, a significant reduction of the tool vibrations by 28% of the vibration amplitude is achieved through the fast design modification, which is comparable to the result from the design optimization.