A one-dimensional dynamic model of thin-walled telescopic boom considering complicated cross-section deformation behaviors

• A data-driven one-dimensional higher-order dynamic modeling method is proposed for telescopic booms, accurately capturing higher-order deformations such as warping and distortion of thin-walled sections. • The displacement transfer matrix at nested joints is derived using the Moore–Penrose pseudoinverse, ensuring deformation compatibility and dynamic coupling between multiple boom segments. • Dynamic condensation via mode superposition is applied to establish a state-space model, and a vibration state observation scheme is proposed based on limited measurement points. • Experimental results demonstrate that the prediction errors for the first six natural frequencies of two- and three-section booms are within 4% and 6%, respectively, and only eight measurement points suffice to effectively capture the global dynamic response. Telescopic booms composed of multiple nested thin-walled segments are susceptible to complex cross-sectional deformations that cannot be adequately captured by conventional beam theories. This paper presents a one-dimensional higher-order dynamic model for telescopic booms, capable of effectively characterizing the intricate cross-sectional deformation mechanisms in both boom segments and thin-walled sliding joints. To accurately capture deformation behaviors of round-corner rectangular segments, a set of cross-section shape functions is constructed using a piecewise-straight approximation enforced by displacement continuity conditions. Furthermore, a data-driven approach leveraging pattern recognition is employed to identify characteristic deformation modes, leading to a condensed higher-order model with fewer degrees of freedoms. For modeling the constraint relationships at nested joints, a transformation matrix is derived via the Moore-Penrose generalized inverse, based on displacement continuity between adjacent segments. To improve the modeling efficiency of the full telescopic boom, dynamic condensation is applied to the system model through mode superposition. The derived model is validated through numerical comparisons with shell theory and alternative beam models, and the influence of complicated cross-section deformation behaviors is systematically investigated. The results demonstrate that the presented model exhibits notable advantages in terms of physical interpretability and computational efficiency.