Multi-shaker half sine shock on random mixed vibration control

Abstract A control method for multi-shaker half sine shock on random mixed vibration test is presented. The key parts of the multi-shaker shock on random vibration control are the generation of desired multi-input drive signals, separation of measured multi-output response signals and control of separated response signals. In this work, the classic half sine shock signal is recalled first and then a compensated half sine shock signal is presented to make sure the velocity and displacement at the end of the signal are zero. A shock on random separation method is proposed based on the kurtosis features of the mixed and separated signals. It is found that the kurtosis of a pure shock signal is only related to the durations of the shock and total signal. Afterwards, the multi-shaker mixed vibration control procedure is formulated. The reference values are composed of the reference spectral densities for the random component and reference amplitudes for the shock component. The shock interval between every two shocks and the time difference of shocks between different control channels can be defined. A simulation example using a cantilever beam system and a triaxial mixed vibration test are provided and the results indicate the validity and feasibility of the proposed methods.