Flutter analysis of a rigid-flexible coupled composite space structure with momentum wheels under thermal load

Abstract

The communication and observation spacecraft generally consists of the spacecraft body, the composite connecting beams, the working payload and the CMG/momentum wheel for integrated attitude-vibration control. When such complex space structure operates in near-Earth orbit, the sudden change in thermal load may cause a solar flux shock to the structure, which is likely to excite the flutter motion of the structure. The flutter mechanism of a rigid-flexible coupled composite space structure configured with the momentum wheel is investigated. In this study, the heat conduction equation of the composite beam appendage is derived. Then, the dynamic equations of the system influenced by the momentum wheel and composite material parameters are obtained based on the Kane's equations. Using the Routh–Hurwitz stability criterion, the stability boundaries of the flexible appendage are obtained for different composite material parameters, different operating conditions of the momentum wheel, and different attitude angular velocities. Finally, the flutter behavior is analyzed based on the dynamic response of the flexible structure and the flutter stability boundaries are verified.