Modelling and testing of a soft suspension design for a reaction/momentum wheel assembly

Abstract

The micro-vibrations generated by equipment onboard spacecraft can significantly affect the performance of sensitive payloads; in particular mid to high frequency band micro-vibrations, are difficult to model and control. This study focuses on the micro-vibrations emitted by a wheel assembly (WA) implementing a soft (flexible) suspension system. Both the soft and a “conventional” rigid design were tested using a Seismic Micro-Vibration Measurement System (SMVMS). A Newton–Euler method was employed to develop an analytical model of the WA and the test system, which was then used to model and analyze the micro-vibrations emitted by the reaction/momentum WA, due to the static and dynamic imbalance of the flywheel. When compared with the traditional “rigid” design, the soft suspension system is shown to effectively reduce the high frequency disturbances, and the mathematical model effectively represents the fundamental harmonic disturbances. In addition, the results confirm that the SMVMS shows relatively high measurement accuracy.