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arXiv · 2412.12035

Backstepping Control of Tendon-Driven Continuum Robots in Large Deflections Using the Cosserat Rod Model

Rana Danesh·Farrokh Janabi-Sharifi
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Abstract

This paper presents a study on the backstepping control of tendon-driven continuum robots for large deflections using the Cosserat rod model. Continuum robots are known for their flexibility and adaptability, making them suitable for various applications. However, modeling and controlling them pose challenges due to their nonlinear dynamics. To model their dynamics, the Cosserat rod method is employed to account for significant deflections, and a numerical solution method is developed to solve the resulting partial differential equations. Previous studies on controlling tendon-driven continuum robots using Cosserat rod theory focused on sliding mode control and were not tested for large deflections, lacking experimental validation. In this paper, backstepping control is proposed as an alternative to sliding mode control for achieving a significant bending. The numerical results are validated through experiments in this study, demonstrating that the proposed backstepping control approach is a promising solution for achieving large deflections with smoother trajectories, reduced settling time, and lower overshoot. Furthermore, two scenarios involving external forces and disturbances were introduced to further highlight the robustness of the backstepping control approach.

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Rana Danesh, Farrokh Janabi-Sharifi. 2024-12-16. Backstepping Control of Tendon-Driven Continuum Robots in Large Deflections Using the Cosserat Rod Model. https://doi.org/10.1016/j.mechmachtheory.2025.105953

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