Active damping control of flexible appendages for spacecraft

Modern spacecraft are usually equipped with various flexible appendages, which bring great challenges to the design of high-performance control systems. This paper proposes a novel approach to provide active damping to spacecraft flexible appendages. Vibrations of flexible appendages are actively attenuated using a base-mounted angular displacement mechanism and tip-mounted non-collocated sensors. Dynamic models are presented and the controller design techniques provided. Effectiveness of the approach is demonstrated through an experimental apparatus, in which the damping ratio of the target beam is increased to be better than 40%. Furthermore, an active damping-control scheme using no extra sensors beyond attitude sensors onboard the spacecraft bus is proposed and demonstrated through numerical simulations.