Novel Active–Passive Piezoelectric Hybrid Constrained-Layer Damping Technique for Vibration Isolation in a Whole Spacecraft

Undesired dynamics during a rocket launch can lead to failures such as the fatigue and fracture of a whole spacecraft. Moreover, low-frequency vibration in a spacecraft cannot effectively be controlled through traditional passive isolation. We thus present a novel active–passive hybrid vibration isolation technique based on a piezoelectric hybrid constrained-layer damping treatment to reduce whole-spacecraft vibration and improve the vibration isolation bandwidth. The new technique has the advantages of an active–passive hybrid piezoelectric network and passive constrained-layer damping features. The installation location and structural form of the presented treatment on the satellite–launch vehicle system are proposed by simplifying the link mode of the satellite and rocket structure. On this basis, governing equations of the simplified whole-spacecraft vibration isolation system with the presented treatment are derived by virtue of Hamilton’s principle combined with the Rayleigh–Ritz method. The active controller is designed by adopting a velocity feedback control strategy. The vibration suppression effect is illustrated in numerical simulations of the open-loop and closed-loop characteristics. It is notable that good vibration attenuation behaviors are realized in the whole-spacecraft hybrid isolation system. Furthermore, a prototype of the system with the presented treatment is designed and experimental investigations are carried out to verify the accuracy of the theoretical investigation, further illustrating the feasibility and effectiveness of the presented control scheme.