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arXiv · 2606.20958

Learning-Based Modeling of Soft Robots via Cosserat Rod Theory

Mohammad Ali·Nithin Senthur Kumar·Eric J. Barth·Thomas Beckers
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Abstract

Modeling soft robot dynamics is challenging due to their continuum structure and typically nonlinear dynamics. Creating models based on first-order principles is typically time-demanding, and their expressiveness is limited, whereas data-driven models lack interpretability and physical consistency. This work aims to overcome these challenges by introducing a port-Hamiltonian Gaussian Process Regression framework for learning and simulating the dynamics of planar, rod-like soft robots. In detail, the proposed model integrates Cosserat rod theory and Hamiltonian physics with data-driven inference to preserve the system's energy structure while accurately learning the rod dynamics. Numerical simulations show that we can achieve accurate and energy-consistent representations of a rod-like soft robot, showing the potential for a robust and interpretable pathway for modeling complex continuum mechanics.

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Mohammad Ali, Nithin Senthur Kumar, Eric J. Barth, Thomas Beckers. 2026-06-18. Learning-Based Modeling of Soft Robots via Cosserat Rod Theory. https://arxiv.org/abs/2606.20958

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