Abstract: The in orbit positioning accuracy of spacecraft is susceptible to the influence of low frequency micro vibrations in the environment and internal disturbances caused by payloads. This study designed a series of piezoelectric actuators with high stiffness for vibration isolation. Firstly, the dynamic model of the piezoelectric isolator and a dual sensor feedback control method were established, and the merits and demerits of the feedback control parameters and anti disturbance characteristics were compared. The feasibility of the piezoelectric isolator proposed was verified through simulation models. Finally, experiments were conducted to confirm the accuracy of the aforementioned design and simulation. The results show that the proposed piezoelectric isolator can provide a basic vibration attenuation capability of -15dB in the 1~25Hz range, and attenuate the resonance peak by -25dB, while also possessing high stiffness characteristics; it can offer excellent low frequency vibration isolation performance and inertial stability, and effectively resist internal disturbances caused by payloads.

Key words: piezoelectric ceramics, active vibration isolation, feedback control, dynamic modeling