Abstract: In experimental modal analysis, it is necessary to measure the response data in directions of all degrees of freedom to obtain the complete mode shape information. In order to decrease the number of measurement points and, especially, to complement the data of those degrees of freedom which are unable to be detected, this paper suggests an approach utilising the analytical relations derived by B.E.M. to extend the dynamic measurement data. By use of this method, in experimental modal analysis, we can take l...