Abstract
Vibration isolation is traditional technique for mitigating structural vibrations, and has been successfully applied to whole-spacecraft vibration isolation. Transmissibility across the isolator, which derived from the single degree-of-freedom vibration isolation system, is usually used to evaluate the performance of the isolator. However, it is not sufficient to evaluate the performance of multi degree-of-freedom system, such as whole-spacecraft vibration isolation. Considering the flexibility of the original payload attachment fitting, the ratio of transmissibility with the isolator to transmissibility with the payload attachment fitting should be used. In order to take into account the flexibility of the spacecraft, transmissibility ratio of more observation nodes in the spacecraft have to be calculated. Furthermore, in order to consider the flexibility of launch vehicle, the response ratio or power flow ratio, which overcomes the limitation of transmissibility, is used to quantify the vibration isolation performance. The method presented here can be applied to other complicated flexible vibration isolation systems.
