Dynamic modeling and control of deployable telescopic tubular masts: Comparative analysis of hybrid coordinate and multibody approaches

Deployable structures play a crucial role in modern spacecraft, enabling compact storage during launch and controlled expansion in orbit. The Telescopic Tubular Mast (TTM) is a one-dimensional deployable structure widely used for positioning payloads such as antennas and solar sails. This paper presents a comparative analysis of two modeling approaches for capturing the dynamic behavior of a spacecraft equipped with TTMs: the Hybrid Coordinate (HC) method, which treats the deployable structure as a single flexible body with time-varying properties, and the multibody approach based on Kane's method, which models each tube section as an independent element with fixed geometry. The study systematically cross-validates these methods, evaluating their computational efficiency, and ability to capture the complex rigid-flexible coupling effects induced by the deployment process. Simulation results demonstrate that deployment dynamics significantly influence spacecraft attitude, with specific deployment speeds exacerbating attitude deviations. Additionally, we extend the analysis to a multi-dimensional deployable system and implement an attitude control strategy to mitigate deployment-induced disturbances. These findings highlight the necessity of specialized modeling techniques for accurately predicting the behavior of deployable structures in space and optimizing deployment strategies for mission-critical applications.