Abstract:For the characteristics of large flexible space structures, considering controlling in independent modal space, a modal filter is designed to pre-filter the modal information collected from the physical space; a modal observer is designed to obtain modal displacement and modal velocity from modal acceleration. Secondly, using the characteristics of independent decoupling of each mode in independent modal space theory, an independent modal space controller based on optimal control is designed. On this basis, considering the external interference signal, a suboptimal controller based on modal filter is designed to form a complete closed-loop active vibration control system for flexible space structure. The simplified vibration control of truss and monoplane panel is verified by simulation. The results show that both controllers can effectively suppress the vibration, and the maximum amplitude is reduced by about half compared with traditional proportional integral differentiation controller, and it has certain anti-interference ability.