Continuous improvement in the accuracy of remote sensing satellite optical imaging equipment places increasingly higher demands on the vibration environment, and the simple linear passive Stewart platform can no longer satisfy the stringent requirements. A new integrated active and passive Stewart vibration damping platform based on the combination of the polygonal diaphragm spring and the piezoelectric actuator is presented. The single leg of this platform is mainly composed of a polygonal diaphragm spring, a piezoelectric actuator, a force sensor and two flexure hinges. To resolve the inherent contradiction between the high static stiffness and the low dynamic stiffness in the traditional linear vibration isolator, this paper proposes a polygonal diaphragm spring, the key component of the vibration isolator, with High-Static-Low-Dynamic (HSLD) characteristics. It enables high static stiffness for static loading and low dynamic stiffness for dynamic vibration reduction of the vibration isolation system. To reduce the amplitude of the resonance peak in the passive vibration isolation system, we connect an active control element consisting of a piezoelectric actuator and a force sensor in series on the basis of the passive diaphragm spring element to control the active vibration. The simulation results show that the active control system using the PIF feedback control algorithm can reduce the peak value of resonance (11.9 dB) by building the effect of ceiling damping through the integral force link in frequency domain, as well as increase the mass matrix term, effectively reducing the natural frequency (20.9 Hz) of the damping system and broadening its damping effect. Meanwhile, it can maintain the high attenuation of the high frequency band, and reduce, in the time domain, the acceleration vibration amplitude of the system from ±0.6 g to ±0.07 g, with the vibration attenuation reaching 88%.
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