Experimental Modal Analysis

  frequency measurement result Copyright: IEM

The dynamic behavior of a mechanical structure can be described by its modal parameters; i.e. natural frequency, mode shape, and modal damping. These parameters are determined through experimental modal analysis. The structure under test is excited with forces generated from an impact hammer or a shaker and the responses are measured with accelerometers. Through Fourier transformation in frequency domain, the transfer functions between excitation and responses are calculated. The results are used to validate results of numerical modal analysis or to parameterize a structural dynamic simulation model. In addition, the experimental modal analysis is used to characterize a testbed in order to avoid excitation of resonance frequencies of a running test bench.