Identification of spindle dynamics by receptance coupling for non-contact excitation system

摘要

The identification of spindle dynamics plays a crucial role in accurate prediction of the stability diagrams for high speed machining operations. In this study, variations of the mode shapes of the tool-spindle assembly at high spindle speeds are examined using numerical models and hypotheses are formulated. An identification method of spindle dynamics is proposed, dedicated to non-contact excitation system; from which only cross FRF can be obtained (instead of tool tip FRF classically). Then, spindle dynamics is calculated using inverse Receptance Coupling (RC) method. Proposed method enables the identification of the speed dependent spindle dynamics in the full frequency range. The approach has been verified with the Finite Element Model (FEM) of a spindle-bearing assembly. The prediction by RC of the dynamics of another tool has been successfully compared to the FEM simulation.