Frequency shaping-based H∞ control for active pneumatic vibration isolation with input voltage saturation

Pneumatic vibration isolators play an increasingly important role in precision manufacturing. In this paper, a H∞ active control strategy for pneumatic vibration isolation system based on voltage input saturation is proposed and studied. The objective is to suppress the resonance peaks and low-frequency vibration disturbances near the intrinsic frequency of the vibration isolation system. The control algorithm is highly robust to system model errors, and frequency characteristic shaping design is performed by selecting appropriate weighting functions according to the performance objectives to achieve maximum vibration suppression in the frequency band where active control is required. Considering the smoothness of the operation of the pneumatic vibration isolation system and the safety of the control channel, input saturation control of the input voltage is carried out. Finally, a 1–10 Hz excitation signal is applied to test the performance of the pneumatic vibration isolation system under this active control method, and the experimental results show the effectiveness of the algorithm.