The space cable-rod deployable articulated mast is a type of space-deployable structure with high storage efficiency. As a critical component, the pretension in the cables directly affects the stiffness and dynamic characteristics of the mast. However, research on the modeling of cable assemblies remains limited, and the relationship between cable tensions and the natural frequencies of the system has not been reported, leaving a lack of design and manufacturing guidelines for such assemblies.
In this study, a dynamic model of the X-configuration cable–strut assembly consisting of a central locking device and four cables was developed, and its applicability was investigated. Guided by the characteristics of the actual structure, the assembly was simplified into a central mass–spring system, and the governing equations of motion were derived using the Newton–Euler formulation. A finite element (FEM) model based on spring elements is constructed to validate the proposed formulations. In addition, another FEM model employing beam elements is developed, and modal analyses are conducted to compare with theoretical predictions, thereby assessing the applicability of the model.
The results demonstrate that the equivalent spring model can accurately capture the first, fourth, and fifth natural frequencies of the system, while its prediction of in-plane frequencies is limited due to the neglect of cable bending effects. Based on the characteristics of the three out-plane modes, explicit relationships between natural frequencies and cable tensions are derived. This work provides new insights into the simplified modeling of cable assemblies and offers valuable references for further refinement and practical applications.