本文研究了带液体晃动和柔性附件的耦合航天器系统在液体燃料耗散和柔性附件扭转振动的作用下,经历从最小惯量轴到最大惯量轴姿态机动中的混沌动力学行为。将液体晃动等效为球摆模型并由此建立了带柔性附件充液航天器多体耦合系统动力学模型。首先推导出耦合系统动力学方程并采用Melnikov积分预测受扰系统稳定与不稳定流形是否横截相交,得到了参数形式表达的混沌运动解析判据,这对航天器的设计有重要的指导意义。研究发现,混沌的发生依赖于刚体形状,阻尼比,充液比和扭转振动频率。此外,在经过被动再定向姿态机动后,由于液体晃动的本质非线性特性,充液航天器最终将进行大章动角的周期极限环运动而非绕着最大惯量轴自旋。
The chaotic dynamics in an attitude maneuver of a coupled slosh-flexible spacecraft from minor axis to major axis under the influence of dissipative effects due to fuel sloshing and a small flexible appendage constrained to undergo only torsional vibration is investigated.The slosh-coupled flexible spacecraft carrying a sloshing liquid is considered in attitude maneuver as multi-body system with the sloshing motion modeled as a spherical pendulum.The focus in this paper is on the way in which the dynamics of the liquid sloshing and flexible appendage vibration are coupled.The equations of motion are derived.Melnikov's integral is used to predict the transversal intersections of the stable and unstable manifolds for the perturbed system.An analytical criterion for chaotic motion is derived in terms of the system parameters.This criterion is evaluated for its significance to the design of spacecraft.The dependence of the onset of chaos on quantities such as body shape,damping ratio,liguid filled ratio and torsional vibration frequency of flexible appendage are investigated.In addition,it is shown that after passive reorientation maneuver,a spacecraft carrying a sloshing liquid will end up with periodic limit loop motion other than a final major axis spin because of the intrinsic non-linearity of fuel slosh.Furthermore,an extensive numerical simulation is carried out to validate the Melnikov's analytical result.