简介：Thestabilityofpartlyliquidfilledspacecraftwithflexibleattachmentwasinvestigatedinthispaper.Liquidsloshingdynamicswassimplifiedasthespring–massmodel,andflexibleattachmentwasmodeledasthelinearshearingbeam.ThedynamicequationsandHamiltonianofthecoupledspacecraftsystemweregivenbyanalyzingtherigidbody,liquidfuel,andflexibleappendage.NonlinearstabilityconditionsofthecoupledspacecraftsystemwerederivedbycomputingthevariationofCasimirfunctionwhichwasaddedtotheHamiltonian.Thestableregionoftheparameterspacewasgivenandvalidatedbynumericalcomputation.Relatedresultssuggestthatthechangeofinertiamatrix,thelengthofflexibleattachment,spacecraftspinningrate,andfilledratioofliquidfueltankhavestronginfluenceonthestabilityofthespacecraftsystem.