航天器挠性附件刚柔耦合动力学建模与仿真

大型挠性航天器在进行轨道机动或姿态调整等大范围刚体运动时,将与其挠性附件的变形运动发生强烈的耦合,传统的零次近似动力学模型已不能正确揭示此时系统的动力学行为。现针对带梁式挠性附件的航天器,在计及挠性附件变形位移场耦合作用的基础上,通过Lagrange方程建立了航天器的刚柔耦合一次近似动力学模型,并利用Wilson-θ方法进行了数值仿真。仿真结果说明,在航天器经历大范围刚体运动时,该动力学模型能够正确预示挠性附件的动力学行为;挠性附件的振动频率随着大范围刚体运动速度的增加而增大,出现了动力刚化现象。

Modeling and Simulation for the Rigid-flexible Coupling Dynamics of the Spacecraft with Flexible Appendages

When the flexible spacecraft was undergoing large overall motions, such as orbit maneuvering and attitude adjusting, the intense coupling motions between the large overall motions and the deformed motions of the flexible appendages appeared. The traditional dynamic models couldn't indicate the dynamics accurately. The rigid-flexible coupling dynamics of the spacecraft with flexible beam-like appendages undergoing large overall motions was investigated in this paper. The rigid-flexible coupling dynamic model with first-order approximation of the spacecraft was derived via Lagrange equations, considering the coupling effects of the deformation of flexible appendages. The numerical simulation, which employed the Wilson-( methods, shows that the dynamic model can incidcate the dynamics accurately. The vibration frequency of the flexible appendages undergoing large overall motions will increase with the augment of the motion velocity, that is the dynamic stiffening.