A complete methodology for estimating dynamics of the heavy machine tool structure

Abstract

Dynamic properties of machine tool structure under machining operations are different from static results of impact or shaker tests. This paper proposes a complete methodology for applying operational modal analysis (OMA) in the case of heavy machine tool to estimate the dynamic modal parameters of the whole structure during machining. A random cutting technique is presented to meet the white noise excitation requirement of OMA. This technique is realized by interrupted cutting of a specially designed workpiece, of which the surface is modulated with pseudorandomly distributed teeth and channels. The resulting cutting force excites the structure in all three directions. Finally, Machine tool dynamic modal parameters are estimated and verified. © 2013 Springer-Verlag Berlin Heidelberg.