Study on the Model Reduction Methods in CNC machine

摘要

In order to research dynamic characters of CNC machine tools, the finite element method is always adopted to model the system, and its dynamic characters are analyzed based on the modeling. The large dimension of the model for CNC machine and its key system become a problem to be solved. In this paper, the model reduce methods are compared and analyzed in order to clarify this problem. The transmission system of CNC machine tool is modeled by FEM firstly, then, the model reduction methods of reduce method, subspace method and Block Lanzcos method are applied for its modal analysis. The reduced method have to search a set of master DoF, the subspace is used for calculating partial mode in a relative large scale system with simple geometries;. Block-Lanczos method is adopted when the system with large scale dimension, but it needs good computer storage capacity and performance;