Modeling and analysis of piezoelectric folded-beam isolator for attenuating micro-vibration in spacecraft

摘要

Design, modeling, and analysis of an intelligent flexible isolation system for attenuating low-frequency micro-vibration are presented. The isolator consists of a payload platform, a supporting platform and four folded-beams with surface-bonded macro-fiber composites (MFCs). To accurately analyze the system performance, a piezoelectric finite element (FE) model is built and validated by the modal analysis results derived from ANSYS. This paper presents an attempt to widen the low-frequency isolation range for the micro-vibration using a modal frequency shift approach. The transfer functions of the active isolation system with different feedback controls are derived based on an FE model, in which feedback signals can be absolute and relative accelerations, absolute and relative displacement, relative velocity, and mixed responses. According to the numerical results, the expected performance of low-frequency vibration isolation can be easily achieved, especially by a kind of mixed responses feedback method. The time-domain simulations also show that the proposed piezoelectric isolation system exhibits a good isolation performance, endowing them with great potential for the micro-vibration restrain in aerospace application.