@article {2020a-NavSabTogPucFra,
	title = {Direct Force Feedback Control and Online Multi-task Optimization for Aerial Manipulators},
	journal = {IEEE Robotics and Automation Letters},
	volume = {5},
	year = {2020},
	month = {04/2020},
	pages = {331-338},
	abstract = {In this paper, we present an optimization-based method for controlling aerial manipulators in physical contact with the environment. The multi-task control problem, which includes hybrid force-motion tasks, energetic tasks, and position/postural tasks, is recast as a quadratic programming problem with equality and inequality constraints, which is solved online. Thanks to this method, the aerial platform can be exploited at its best to perform the multi-objective tasks, with tunable priorities, while hard constraints such as contact maintenance, friction cones, joint limits, maximum and minimum propeller speeds are all respected. An on-board force/torque sensor mounted at the end effector is used in the feedback loop in order to cope with model inaccuracies and reject external disturbances. Real experiments with a multi-rotor platform and a multi-DoF lightweight manipulator demonstrate the applicability and effectiveness of the proposed approach in the real world.},
	keywords = {Aerial Physical Interaction, Aerial Robotics},
	doi = {10.1109/LRA.2019.2958473},
	attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/2020a-NavSabTogPucFra.pdf , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2020a-NavSabTogPucFra.mp4},
	author = {Gabriele Nava and Quentin Sabl{\'e} and Marco Tognon and Daniele Pucci and Antonio Franchi}
}
@article {2019k-FurNaiZacFra,
	title = {Input Allocation for the Propeller-Based Overactuated Platform ROSPO},
	journal = {IEEE Trans. on Control Systems Technology},
	volume = {18},
	year = {2019},
	month = {11/2020},
	pages = {2720-2727},
	abstract = {We apply input allocation to a redundantly actu- ated platform driven by tilting aerodynamic propulsion units: the ROtor graSPing Omnidirectional (ROSPO). This platform represents a novel testbed for redundancy allocation designs in propeller driven platforms. The control solution is based on a hierarchical architecture, made of a high level controller for trajectory tracking, and a nonlinear input allocation algorithm. The algorithm exploits the input redundancy to take into account soft constraints associated to physical saturation limits of the actuators, and also induce reduced energy consumption. The actuator dynamics is fully taken into account in the framework and a rigorous proof of asymptotic tracking of time-varying references is guaranteed despite the impossibility of an instanta- neous force execution. The experiments on the ROSPO platform clearly show the practicability and effectiveness of the proposed approach, as well as its scalability with different degrees of over- actuation levels.},
	doi = {10.1109/TCST.2019.2944341},
	attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/2019k-FurNaiZacFra.pdf},
	author = {Michele Furci and Carlo Nainer and Luca Zaccarian and Antonio Franchi}
}
@article {2017k-NesRobBueFra,
	title = {Decentralized Simultaneous Multi-target Exploration using a Connected Network of Multiple Robots},
	journal = {Autonomous Robots},
	volume = {41},
	year = {2017},
	month = {03/2016},
	pages = {989-1011},
	abstract = {This paper presents a novel decentralized control strategy for a multi-robot system that enables parallel multi-target exploration while ensuring a time-varying connected topology in cluttered 3D environments. Flexible continuous connectivity is guaranteed by building upon a recent connectivity maintenance method, in which limited range, line-of-sight visibility, and collision avoidance are taken into account at the same time.
Completeness of the decentralized multi-target exploration algorithm is guaranteed by dynamically assigning the robots with different motion behaviors during the exploration task. One major group is subject to a suitable downscaling of the main traveling force based on the traveling efficiency of the current leader and the direction alignment between traveling and connectivity force. This supports the leader in always reaching its current target and, on a larger time horizon, that the whole team realizes the overall task in finite time.
Extensive Monte~Carlo simulations with a group of several quadrotor UAVs show the scalability and effectiveness of the proposed method and experiments validate its practicability. },
	keywords = {Connectivity maintenance, Exploration, Motion control of multiple robots, Patrolling / Surveillance},
	attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/1505.05441v3.pdf , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2016g-NesRobBueFra-exp.mp4 , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2016g-NesRobBueFra-empty.mp4 , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2016g-NesRobBueFra-office.mp4 , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2016g-NesRobBueFra-town.mp4},
	author = {Thomas Nestmeyer and Paolo Robuffo Giordano and Heinrich H. B{\"u}lthoff and Antonio Franchi}
}
@conference {2017j-NaiFurSeuZacFra,
	title = {Hierarchical Control of the Over-Actuated ROSPO Platform via Static Input Allocation},
	booktitle = {20th IFAC World Congress},
	year = {2017},
	month = {07/2017},
	address = {Toulouse, France},
	abstract = {This paper addresses the problem of control allocation applied to an over-actuated hovercraft-type vehicle. A hierarchical control architecture, consisting of a high level controller for trajectory tracking, and a control allocation algorithm, is developed and proved to be effective in tracking a desired trajectory while optimizing some cost related to actuator constraints. The control allocation algorithm exploits the redundancy of the system in order to keep the actuator states inside their saturation limits and tries to minimize the power consumption of the propellers. Unlike other papers on control allocation, actuator dynamics is taken into account. The control architecture is tested through simulations that well illustrate the capabilities of the proposed control design},
	attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/2017j-NaiFurSeuZacFra-preprint.pdf},
	author = {Carlo Nainer and Michele Furci and Alexandre Seuret and Luca Zaccarian and Antonio Franchi}
}
@inbook {2013n-SpeNotBueFra,
	title = {Aggressive Maneuver Regulation of a Quadrotor UAV},
	booktitle = {Robotics Research, The 16th International Symposium ISRR},
	volume = {114},
	number = {Springer Tracts in Advanced Robotics},
	year = {2016},
	month = {04/2016},
	pages = {95-112},
	publisher = {Springer},
	organization = {Springer},
	abstract = {In this paper we design a nonlinear controller for aggressive maneuvering of a quadrotor. We take a maneuver regulation perspective. Differently from the classical trajectory tracking approach, maneuver regulation does not require following a timed reference state, but a geometric {\textquotedblleft}path{\textquotedblright} with a velocity (and possibly orientation) profile assigned on it. The proposed controller re- lies on three main ideas. Given a desired maneuver, i.e., a set of state trajectories equivalent under time translations, the system dynamics is decomposed into dynamics longitudinal and transverse to the maneuver. A space-dependent version of the transverse dynamics is derived, by using the longitudinal state, i.e., the arc-length of the path, as an independent variable. Then the controller is obtained as a function of the arc-length consisting of two terms: a feedforward term, being the nominal input to apply when on the path at the current arc-length, and a feedback term exponentially stabilizing the state-dependent transverse dynamics. Numerical computations are presented to prove the effectiveness of the proposed strategy. The controller performances are tested in presence of uncertainty of the model parameters and input noise and saturations. The controller is also tested in a realistic simulation environment validated against an experimental test-bed.},
	keywords = {Aerial Robotics},
	attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/2013n-SpeNotBueFra-preprint.pdf , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2013n-SpeNotBueFra-1_no_sat.mp4 , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2013n-SpeNotBueFra-1_no_sat_zoom.mp4 , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2013n-SpeNotBueFra-2_sat_8_5.mp4 , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2013n-SpeNotBueFra-2_sat_8_5_zoom.mp4 , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2013n-SpeNotBueFra-2_sat_7.mp4 , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2013n-SpeNotBueFra-2_sat_7_zoom.mp4},
	author = {Sara Spedicato and Giuseppe Notarstefano and Heinrich H. B{\"u}lthoff and Antonio Franchi}
}
@conference {2016a-SpeFraNot,
	title = {From Tracking to Robust Maneuver Regulation: an Easy-to-Design Approach for VTOL Aerial Robots},
	booktitle = {2016 IEEE Int. Conf. on Robotics and Automation},
	year = {2016},
	month = {05/2016},
	pages = {2965-2970},
	address = {Stockholm, Sweden},
	abstract = {In this paper we present a maneuver regulation scheme for Vertical Take-Off and Landing (VTOL) micro aerial vehicles (MAV). Differently from standard trajectory tracking, maneuver regulation has an intrinsic robustness due to the fact that the vehicle is not required to chase a virtual target, but just to stay on a (properly designed) desired path with a given velocity profile. In this paper we show how a robust maneuver regulation controller can be easily designed by converting an existing tracking scheme. The resulting maneuvering controller has three main appealing features, namely it: (i) inherits the robustness properties of the tracking controller, (ii) gains the appealing features of maneuver regulation, and (iii) does not need any additional tuning with respect to the tracking controller. We prove the correctness of the proposed scheme and show its effectiveness in experiments on a nano-quadrotor. In particular, we show on a nontrivial maneuver how external disturbances acting on the quadrotor cause instabilities in the standard tracking, while marginally affect the maneuver regulation scheme.},
	keywords = {Aerial Robotics},
	attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/2016a-SpeFraNot-preprint.pdf , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2016a-SpeFraNot.mp4},
	author = {Sara Spedicato and Antonio Franchi and Giuseppe Notarstefano}
}
@booklet {2013l-NesRobFra,
	title = {Human-assisted Parallel Multi-target Visiting in a Connected Topology},
	howpublished = {6th Int. Work. on Human-Friendly Robotics},
	year = {2013},
	month = {10/2012},
	address = {Rome, Italy},
	keywords = {Bilateral Shared Control of Mobile Robots, Connectivity maintenance, Motion control of multiple robots},
	author = {Thomas Nestmeyer and Paolo Robuffo Giordano and Antonio Franchi}
}
@booklet {2013h-NesRieLaeHarBotRobFra,
	title = {Interactive Demo: Haptic Remote Control of Multiple UAVs with Autonomous Cohesive Behavior},
	howpublished = {Int. Work. on Towards Fully Decentralized Multi-Robot Systems: Hardware, Software and Integration, at 2013 IEEE Int. Conf. on Robotics and Automation},
	year = {2013},
	month = {05/2013},
	address = {Karlsruhe, Germany},
	keywords = {Bilateral Shared Control of Mobile Robots, Connectivity maintenance, Middleware for robotics, UAV hardware platforms},
	url = {http://icra2013mrs.tuebingen.mpg.de/},
	author = {Thomas Nestmeyer and Martin Riedel and Johannes L{\"a}chele and Simon Hartmann and Fiete Botschen and Paolo Robuffo Giordano and Antonio Franchi}
}
@booklet {2012f-NesRobFra,
	title = {Multi-target Simultaneous Exploration with Continual Connectivity},
	howpublished = {2th Int. Work. on Crossing the Reality Gap - From Single to Multi- to Many Robot Systems, at 2013 IEEE Int. Conf. on Robotics and Automation},
	year = {2013},
	month = {05/2013},
	address = {Karlsruhe, Germany},
	keywords = {Connectivity maintenance, Exploration, Motion control of multiple robots},
	author = {Thomas Nestmeyer and Paolo Robuffo Giordano and Antonio Franchi}
}
