An integrated dynamic modeling and stiffness compensation approach for precision roller rotary table machine
摘要
The effectiveness of roller rotary table machine tools is crucial for high-precision multi-axis CNC machining, yet stiffness variations at different angular positions induce vibrations and machining errors. Despite advancements in rotary table technology, the influence of spatial location on modal properties and stiffness behavior remains underexplored. This study employs a hybrid numerical-experimental approach integrating modal analysis, static stiffness evaluation, and deformation compensation. Modal analysis confirmed the impact of angular orientation on structural dynamics, with the peak natural frequency of 719.07 Hz at + 90°, signifying increased rigidity. At the same time, intermediate angles exhibited reduced stiffness, necessitating adaptive vibration control. Finite element analysis-based static stiffness assessment across six angular configurations (+ 30°, − 30°, + 60°, − 60°, + 90°, and − 90°) revealed maximum deformation at − 90° (0.896 μm) and minimum at + 90° (0.508 μm). A stress transformation model using homogeneous transformation matrices and spatial mapping accurately captured deformation patterns, enabling precise stiffness compensation. An error compensation framework, incorporating an arithmetic mean error correction (AME = 0.74 μm), minimized residual stiffness variations, improving machining stability, tool positioning accuracy, and vibration suppression. This study provides a systematic computational-experimental method to assess and optimize stiffness variability in roller rotary tables, enhancing rigidity consistency in high-precision machining applications.