Effects Analysis Of Reaction Wheel Disturbance On Structure Dynamic Characters Of Spacecraft

Reaction wheel is one of the disturbance sources for satellite structures, which leads to vibration of the satellite structures and decrease the work capability and pointing precision of the sensitive equipments. Therefore, in order to analyze the effects of reaction wheel disturbance to satellite structures dynamic characteristics, in this paper, the effects of reaction wheel disturbance on structure dynamic characteristics of spacecraft are studied, and the contents are as following:First, according to the characteristics of reaction wheel, assuming the disturbance is formed by a series of discrete harmonics, the disturbance force(moment) and rotation speed is proportional to thehe square. The experimental model of reaction wheel disturbance is established based on the assumptions using parameter identification method, which is the disturbance input for further analysis of reaction wheel disturbance on the spacecraft structure dynamic characteristics.Second, the finite element model of the spacecraft is established, and modal analysis of the spacecraft structure is made for the ground case. Then the reaction wheel disturbance is iapplied on the structure, and the effects of reaction wheel disturbance on structure dynamic characteristics of spacecraft for ground case are studied.Then, the finite element model of the on-orbit spacecraft is established, and analysed the natural frequency and reaction disturbance on dynamic characteristics of on-orbit spacecraft structure. And the strain distribution of spacecraft stucture is presented.The effects of reaction disturbance on the dynamic characteristics between the on-orbit case and ground case are compared. Finally, the dynamic response data is picked and then, the transmission characteristics of reaction wheel disturbance are obtained based on parameter identification. It can provide mechanical model for the control of the orbit spacecraft, which is useful for providing effective vibration control strategy.This paper analysed dynamic characteristics of the spacecraft structural caused by the reaction wheel disturbance, and the research results will be providing the support for vibration abatement of the spacecraft.