The complex modal analysis approach was employed to analyze the dynamics of mechanical structures. The results are compared with those by the real modal analysis.
First, a 3 degree of freedom lumped mass system was analyzed using simulated transfer functions. Then, a cantilever and a lathe were analyzed based upon the experimental data.
Through the procedure, differences between the maximum relative displacements at a testing point and a reference point was defined. Based on these, the real modal vectors and the complex modal vectors were compared.
The results show that the complex modal analysis approach has more advantages in accuracy view points and that the real modal analysis approach may yield severely warped results in some cases.
