PROJECT TITLE :

Medium-frequency disturbance attenuation for the spacecraft via virtual-gimbal tilting of the magnetically suspended reaction wheel

ABSTRACT:

A medium-frequency disturbance attenuation strategy based on the virtual-gimbal result of the active magnetically suspended reaction wheels (MSRWs) is proposed to boost the pointing stability for the high-resolution observation of the spacecraft. The disturbances decreasing the pointing stability include not solely the area setting disturbances with low frequency but conjointly the versatile modes and vibrations with medium frequency which are excited by the flexible appendix and therefore the rotating elements. The model of the MSRW is made firstly and also the model of the spacecraft with one MSRW is then developed. Furthermore, a hybrid 3-loop management strategy is meant to stabilise the pointing of the spacecraft and the MSRW, where the compensation loop is used to attenuate the medium-frequency disturbances beyond the bandwidth of the attitude management loop. The bandwidth of the MSRW is expanded by tilting the rotor shaft, and also the attitude angular velocity is directly feedback to the compensation loop. Also, the cross feedback management is introduced to attenuate the medium-frequency disturbances. Finally, simulations are constructed and the results indicate the medium-frequency disturbances are effectively attenuated.