Abstract. Considering the uncertainty of air-magnet active vibration isolation system (AMAVIS), passive vibration isolation was combined with active vibration isolation, which adopted H∞ control strategies. System identification method was used to get the channel model. By adopting mixed sensitivity design strategy, weighting functions were chosen and H∞ controller was designed. Both simulation results and experimental results show AMAVIS based on H∞ control had satisfying effect of vibration reduction in assigned frequency band.

Abstract. The methods of the identification modeling of air-magnet active vibration isolation system (AMAVIS) are studied. Difference equation model and transfer function model are established respectively in the time domain and frequency domain. The models are analyzed and proved by the experiment. Identification results show that the order of frequency identification is higher than the time identification model. But when it comes to accuracy and convergence, frequency identification model has obvious advantage. This paper provides evidence for subsequent active vibration control. The conclusion is the basic of subsequent experiment and research.