@article {2022d-SanTogJimCorFra,
	title = {Indirect Force Control of a Cable-suspended Aerial Multi-Robot Manipulator},
	journal = {IEEE Robotics and Automation Letters},
	volume = {7},
	year = {2022},
	month = {07/2022},
	pages = {6726-6733},
	doi = {10.1109/LRA.2022.3176457},
	attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/2022d-SanTogJimCorFra.pdf , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2022d-SanTogJimCorFra-video.mp4},
	author = {Dario Sanalitro and Marco Tognon and Anotnio-Enrique Jimenez-Cano and Juan Cort{\'e}s and Antonio Franchi}
}
@conference {2020k-UmiTogSanOriFra,
	title = {Communication-based and Communication-less approaches for Robust Cooperative Planning in Construction with a Team of UAVs},
	booktitle = {2020 Int. Conf. on Unmanned Aircraft Systems},
	year = {2020},
	month = {07/2020},
	address = {Athens, Greece},
	abstract = {In this paper, we analyze the coordination problem of groups of aerial robots for assembly applications. With the enhancement of aerial physical interaction, construction applications are becoming more and more popular. In this domain, the multi-robot solution is very interesting to reduce the execution time. However, new methods to coordinate teams of aerial robots for the construction of complex structures are required. In this work, we propose an assembly planner that considers both assembly and geometric constraints imposed by the particular desired structure and employed robots, respectively. An efficient graph representation of the task dependencies is employed. Based on this framework, we design two assembly planning algorithms that are robust to robot failures. The first is centralized and communication-based. The second is distributed and communication-less. The latter is a solution for scenarios in which the communication network is not reliable. Both methods are validated by numerical simulations based on the assembly scenario of Challenge 2 of the robotic competition MBZIRC2020.},
	attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/2020k-UmiTogSanOriFra.pdf , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2020k-UmiTogSanOriFra.mp4},
	author = {Elena Umili and Marco Tognon and Dario Sanalitro and Giuseppe Oriolo and Antonio Franchi}
}
@article {2020b-SanSavTogCorFra,
	title = {Full-pose Manipulation Control of a Cable-suspended load with Multiple UAVs under Uncertainties},
	journal = {IEEE Robotics and Automation Letters},
	volume = {5},
	year = {2020},
	month = {04/2020},
	pages = {2185-2191},
	abstract = {In this work, we propose an uncertainty-aware controller for the Fly-Crane system, a statically rigid cable-suspended aerial manipulator using the minimum number of aerial robots and cables. The force closure property of the Fly- Crane makes it ideal for applications where high precision is required and external disturbances should be compensated. The proposed control requires the knowledge of the nominal values of a minimum number of uncertain kinematic parameters, thus simplifying the identification process and the controller implementation. We propose an optimization-based tuning method of the control gains that ensures stability despite parameter uncertainty and maximizes the H$\infty$ performance. The validity of the proposed framework is shown through real experiments.},
	doi = {10.1109/LRA.2020.2969930},
	attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/2020b-SanSavTogCorFra.pdf , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2020b-SanSavTogCorFra.mp4},
	author = {Dario Sanalitro and Heitor J. Savino and Marco Tognon and Juan Cort{\'e}s and Antonio Franchi}
}
@conference {2020h-PetSanTogMilCorFra,
	title = {Inertial Estimation and Energy-Efficient Control of a Cable-suspended Load with a Team of UAVs},
	booktitle = {2020 Int. Conf. on Unmanned Aircraft Systems},
	year = {2020},
	month = {07/2020},
	address = {Athens, Greece},
	abstract = {The Fly-Crane is a multi-robot aerial manipulator system composed of three aerial vehicles towed to a platform by means of six cables. This paper presents a method to estimate the mass and the position of the center of mass of a loaded platform (i.e. the Fly-Crane platform including a transported load). The precise knowledge of these parameters allows to sensibly minimize the total effort exerted during a full-pose manipulation task The estimation is based on the measure of the forces applied by the aerial vehicles to the platform in different static configurations. We demonstrate that only two different configurations are sufficient to estimate the inertial parameters. Far-from-ideal numerical simulations show the effectiveness of the estimation method. Once the parameters are estimated, we show the enhancement of the system performances by minimizing the total exerted effort. The validity of the proposed algorithm in non-ideal conditions is presented through simulations based on the Gazebo simulator.},
	doi = {10.1109/ICUAS48674.2020.9213842},
	attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/2020h-PetSanTogMilCorFra.pdf},
	author = {Antonio Petitti and Dario Sanalitro and Marco Tognon and A. Milella and Juan Cort{\'e}s and Antonio Franchi}
}
@article {2019l-GabTogPalFra,
	title = {A Study on Force-based Collaboration in Swarms},
	journal = {Swarm Intelligence},
	volume = {14},
	year = {2019},
	month = {11/2019},
	pages = {57-82},
	abstract = {Cooperative manipulation is a basic skill in groups of humans, ani- mals, and in many robotic applications. Besides being an interesting challenge, communication-less approaches have been applied to groups of robots in order to achieve higher scalability and simpler hardware and software design. We present a generic model and control law for robots cooperatively manipulating an object, for both ground and floating systems.
The control method exploits a leader-follower scheme and is based only on implicit communication (i.e., the sensing of contact forces). The control objective mainly consists of steering the object manipulated by the swarm of robots to a desired position and orientation in a cooperative way. For a system with just one leader, we present analytical results on the equilibrium configurations and their stability that are then validated by numerical simulations. The role of object in- ternal forces (induced by the robots through contact forces) is discussed in terms of convergence of the object position and orientation to the desired values. We also present a discussion on additional properties of the controlled system that were investigated using thorough numerical analysis, namely, the robustness of the system when the object is subject to external disturbances in non-ideal condi- tions, and how the number of leaders in the swarm can affect the aforementioned convergence and robustness.},
	doi = {10.1007/s11721-019-00178-7},
	attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/2019l-GabTogPalFra.pdf},
	author = {Chiara Gabellieri and Marco Tognon and Dario Sanalitro and Lucia Pallottino and Antonio Franchi}
}
