Characterization of Machine Tool Vise Using Operational Modal Analysis

摘要

It is important to use realistic boundary conditions when modelling flexible workpieces in machining applications. The boundary conditions imposed by a vise are complex due to e.g. friction and contact phenomena. This work investigates whether approximating the properties of a vise using linear stiffness parameters provides more accurate model results. Vibrational experiments are conducted using operational modal analysis, and a finite element model of the workpiece is used to predict the response. Least-square minimization of the dynamic-residuals are utilized to fit linear stiffness coefficients of the boundary conditions to match experimental and model response. A domain is machined of the part, to clarify whether the identified stiffness coefficients are indeed boundary behaviour or not. Findings include both rigid-body-motion of the workpiece and more accurate model response using identified boundary parameters.