Improving exciter performance in modal testing

Analytical and experimental results are presented to reveal the various factors that effect the force frequency spectrum obtained when using impact hammer and electromagnetic exciters. The transient response of a piezoelectric impact hammer is related to its time constant. A diode and acceleration compensation techniques are proposed for improving the hammer's force signal. The mass of an electromagnetic exciter and the type of driving source used for excitation are related to the force response. A feedback process is proposed for improving the force performance in modal tests.