This research presents a dynamic modeling framework and parameter identification methods for describing the highly nonlinear behaviors of flexibly connected dual-AUV systems. The modeling framework is established based on the lumped mass method, integrating axial elasticity, bending stiffness, added mass and hydrodynamic forces, thereby accurately capturing the time-varying response of the forces and cable configurations. To address the difficulty of directly measuring material-related and hydrodynamic coefficients, this research proposes a parameter identification method that combines the physical model with experimental data. High-precision inversion of the equivalent Youngs modulus and hydrodynamic coefficients is performed through tension experiments under multiple configurations, effectively demonstrating that the identified model maintains predictive consistency in various operational conditions. Further numerical analysis indicates that the dynamic properties of flexible cable exhibit significant nonlinear characteristics, which are highly dependent on material property variations and AUV motion conditions. This nonlinear dynamic behavior results in two typical response states, slack and taut, which are jointly determined by boundary conditions and hydrodynamic effects, significantly affecting the cable configuration and endpoint loads. In this research, the dynamics of flexible cables under complex boundary conditions is revealed, providing a theoretical foundation for the design, optimization and further control research of similar systems.

翻译：本研究提出了用于描述柔性连接双AUV系统高度非线性行为的动态建模框架与参数辨识方法。该建模框架基于集中质量法建立，综合了轴向弹性、弯曲刚度、附加质量及水动力，从而精确捕捉缆索受力与构型的时变响应。针对材料相关参数与水动力系数难以直接测量的问题，本研究提出了一种将物理模型与实验数据相结合的参数辨识方法。通过多种构型下的张力实验，实现了等效杨氏模量与水动力系数的高精度反演，有效证明了辨识模型在不同工况下均保持预测一致性。进一步的数值分析表明，柔性缆索的动态特性呈现出显著的非线性特征，其高度依赖于材料属性变化与AUV运动条件。这种非线性动态行为导致两种典型的响应状态——松弛与张紧，它们由边界条件与水动力效应共同决定，并显著影响缆索构型与端点载荷。本研究揭示了复杂边界条件下柔性缆索的动力学特性，为同类系统的设计、优化及进一步的控制研究提供了理论基础。