The receptance sensitivity and the effect of concentrated mass inserts on the modal balance of spindle-bearing systems

Abstract

In this paper, it is shown how the receptance of a modified system can be described in terms of the receptance of the unmodified system. Furthermore, a receptance sensitivity analysis is introduced to show the effects of design changes on the dynamic performance of vibrating structures. The spindle-bearing system is chosen as a good target for investigation with respect to machine tool's performance. The sensitivity analysis carried out shows the effect of concentrated mass inserrts on its dynamic behaviour. The concept of modal flexibility sharing is chosen as a good measure of modal balance of the vibrating structure. Therefore, a technique is introduced based on the aforementioned method to achieve such state of modal balance by means of some mass inserts. The results obtained lead one to think that such a procedure can be employed to optimise the vibration behaviour of structures in general and machine tools in particular.