Nonlinear control and stability analysis of a unified Tethered UAV-winder system
Samuel Folorunsho, Maggie Ni, William Norris
TL;DR
The paper addresses persistent TUAV operation by coupling a 3D UAV–winder system with a non-taut catenary tether, modeled in full 3D and governed by nonlinear dynamics. It jointly designs onboard altitude/attitude controllers and ground-winder control using nonlinear backstepping, backed by composite Lyapunov analysis to guarantee asymptotic stability. The approach yields accurate tracking of linear and circular trajectories while preserving the tether’s catenary shape, with tether-length adaptation ensuring stability under varied paths. Practically, this enables stable, long-duration tethered UAV missions for surveillance, monitoring, and data collection, with simulations and animations validating performance.
Abstract
This paper presents the development of a comprehensive dynamics and stabilizing control architecture for Tethered Unmanned Aerial Vehicle (TUAV) systems. The proposed architecture integrates both onboard and ground-based controllers, employing nonlinear backstepping control techniques to achieve asymptotic stability of the TUAV's equilibrium. The onboard controllers are responsible for the position and attitude control of the TUAV, while the ground controllers regulate the winder mechanism to maintain the desired tether length, ensuring it retains its catenary form. Simulation results demonstrate the ability of the TUAV system to accurately track linear and circular trajectories, ensuring robust performance under various operational scenarios. The code and movies demonstrating the performance of the system can be found at https://github.com/sof-danny/TUAV\_system\_control.