Structural analysis and characterisation technique applied to a CNC vertical machining centre

Abstract

There is a requirement for improved 3D surface characterisation and reduced tool wear, when modern computer numerical-controlled (CNC) machine tools are operating at high cutting velocities, spindle speeds and feed-rates. This research project investigates vibration-induced errors on a CNC vertical machining centre under dynamic conditions. A model of the machine structural dynamics is constructed using the Finite Element Method (FEM) for the comprehensive analytical investigation of the machine vibration behaviour. The analytical model is then validated against the measured results obtained from an experimental modal analysis (EMA) investigation. A correlation analysis of the simulated and experimental modal analysis results is undertaken in order to improve the accuracy of the model and minimise modelling practice errors. The resulting optimised model will need further sensitivity analysis utilising parametric structural analysis and characterisation techniques in order to identify a potential for vibration reduction using passive methods.