@article {2018h-TogGabPalFra,
	title = {Aerial Co-Manipulation with Cables: The Role of Internal Force for Equilibria, Stability, and Passivity},
	journal = {IEEE Robotics and Automation Letters, Special Issue on Aerial Manipulation},
	volume = {3},
	year = {2018},
	note = {Also selected for presentation at the 2018 IEEE Int. Conf. on Robotics and Automation, Brisbane , Australia},
	month = {02/2018},
	pages = {2577-2583},
	abstract = {This paper considers the cooperative manipulation of a cable-suspended load with two generic aerial robots without the need of explicit communication. The role of the internal force for the asymptotic stability of the beam position-and- attitude equilibria is analyzed in depth. Using a nonlinear Lyapunov-based approach, we prove that if a non-zero internal force is chosen, then the asymptotic stabilization of any desired beam attitude can be achieved with a decentralized and communication-less master-slave admittance controller. If, conversely, a zero internal force is chosen, as done in the majority of the state-of-the-art algorithms, the attitude of the beam is not controllable without communication. Furthermore, we formally prove the output-strictly passivity of the system with respect to an energy-like storage function and a certain input-output pair. This proves the stability and the robustness of the method during motion and in non-ideal conditions. The theoretical findings are validated through extensive simulations.},
	doi = {10.1109/LRA.2018.2803811},
	attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/2018h-TogGabPalFra-preprint.pdf},
	author = {Marco Tognon and Chiara Gabellieri and Lucia Pallottino and Antonio Franchi}
}
