Identification of the Joint Structural Parameters of Machine Tool by DDS and FEM

Abstract

A unique methodology is proposed to identify the joint structural parameters of the machine tool by combining the Dynamic Data System (DDS) methodology with the Finite Element Method (FEM). The structural parameter identification of a simple system with complete modal matrix is introduced together with the modal analysis by the DDS method. The simulation study of a two degree-of-freedom system shows the high accuracy of the identification procedure. The identification of joint parameters of a general system with an incomplete mode shape is analyzed next. The condensation and digital filtering techniques are developed for this purpose. In a shaft model experiment the joint parameters are identified when the response data at boundary points are difficult to be measured. Furthermore, a column model experiment revealed the ability of the proposed identification technique to deal with a large number degree-of-freedom system.