Predicting dynamic behaviours of a whole machine tool structure based on computer-aided engineering

A systematic procedure is proposed to predict the dynamic behaviours of a whole machine-tool structure. The prediction procedure makes use of a receptance synthesis method, in which the dynamic model is composed of the elements such as the distributed-mass beam, the lumped mass and the joint. As an example, the dynamic characteristics of a guideway joint are analysed through the use of the dynamic fundamental characteristic parameters of joint surfaces at unit area obtained by experiments. The software to predict the dynamic behaviours of a whole machining tool structure is developed based upon the procedure. To demonstrate the utility of the proposed procedure and the developed software, the dynamic modeling of a whole machining centre structure has been established and its natural frequencies are calculated by the software. The dynamic test for the whole machining centre showed that the procedure and the software is valid to predict dynamic behaviours of a whole machine-tool structure at its design stage.