Design of a 6-DOF Aerial Hybrid Cable-Driven Parallel Manipulator

This paper presents the design of a 6-degree-of-freedom (DOF) hybrid cable-driven parallel manipulator (HCDPM) with a central elastic rod. HCDPM is integrated with a multi-rotor unmanned aerial vehicle (UAV) for the contact inspection of floating offshore wind turbines (FOWTs) by delivering a sensor. Flexible cables allow the end-effector (EE) to actively adapt to the target’s movements during approach. Once the EE attaches to the target, the central rod detaches from the EE and the cables slacken. This setup enables the sensor to directly detect signals from the FOWTs without being influenced by the UAV’s movements and vibrations, thanks to the unidirectional tension transmission in the cables. Finally, the accuracy of the modeling and the significance of introducing the central rod were validated through co-simulation and workspace calculation. The results indicate that the inclusion of the rod significantly improves the model’s precision, design’s stiffness, and the workspace.