APPARATUS FOR AND METHOD OF RANDOM VIBRATION CONTROL

摘要

In order to ensure that the vibrations of a system under test are in accordance with a reference spectral density Z(w), the system is driven by a signal xn(t) provided by an inverse discrete Fourier transform (IDFT) with random phases introduced by a function Rn(w) and the response spectral density Yn(w) provided by a DFT is brought into agreement with Z(w) by a feedback loop. Moreover, in order to ensure that this is done in one iteration, X'n(w) is derived from xn(t) by a DFT and divided by Yn(w) and the quotient is multiplied with Z(w) to provide the new input xn(w) for the IDFT. The division cancels out the random factor which is present in both X'n(w) and Yn(w).The system thus equalizes both rapidly and stably.