Prediction of dynamic response in a cantilever beam using a smoothed version of the experimental modal matrix

Resumo

It is not economically viable, nor technically interesting the installation of accelerometers in all locations
of interest in a given machine or structure. To estimate vibration responses in non-instrumented locations, a
smoothed and expanded version of the experimental modal matrix can be employed. For this, a finite element
model and operational modal analysis can be used. In this work, we used a smoothed version of the experimental
modal matrix of a cantilever rectangular aluminum beam, to estimate vibration responses. Impact test and the
EFDD method were used for modal parameter identification. The SEREP reduction technique was used to match
numerical DOFs with the measured ones. Then, the local correspondence principle (LC) was used to smooth the
measured DOFs in the experimental modal matrix. Finally, the smoothed version of the experimental modal matrix
was used to estimate the acceleration signal in DOF no.5 and results showed high accuracy between the measured
and the estimated signals.