Nicola Lissandrini; Giulia Michieletto; Riccardo Antonello; Marta Galvan; Alberto Franco; Angelo Cenedese Cooperative Optimization of UAVs Formation Visual Tracking (Journal Article) Robotics, 8 (3), pp. 1–22, 2019. (Abstract | Links | BibTeX | Tags: coverage, multi-agent, optimization, UAVs, visual tracking) @article{Lissandrini2019, title = {Cooperative Optimization of UAVs Formation Visual Tracking}, author = {Nicola Lissandrini and Giulia Michieletto and Riccardo Antonello and Marta Galvan and Alberto Franco and Angelo Cenedese }, url = {https://www.mdpi.com/2218-6581/8/3/52}, doi = {https://doi.org/10.3390/robotics8030052}, year = {2019}, date = {2019-07-07}, journal = { Robotics}, volume = {8}, number = {3}, pages = {1--22}, abstract = {The use of unmanned vehicles to perform tiring, hazardous, repetitive tasks, is becoming a reality out of the academy laboratories, getting more and more interest for several application fields from the industrial, to the civil, to the military contexts. In particular, these technologies appear quite promising when they employ several low-cost resource-constrained vehicles leveraging their coordination to perform complex tasks with efficiency, flexibility, and adaptation that are superior to those of a single agent (even if more instrumented). In this work, we study one of said applications, namely the visual tracking of an evader (target) by means of a fleet of autonomous aerial vehicles, with the specific aim of focusing on the target so as to perform an accurate position estimation while concurrently allowing a wide coverage over the monitored area so as to limit the probability of losing the target itself. These clearly conflicting objectives call for an optimization approach that is here developed: by considering both aforementioned aspects and the cooperative capabilities of the fleet, the designed algorithm allows controling in real time the single fields of view so as to counteract evasion maneuvers and maximize an overall performance index. The proposed strategy is discussed and finally assessed through the realistic Gazebo-ROS simulation framework.}, keywords = {coverage, multi-agent, optimization, UAVs, visual tracking}, pubstate = {published}, tppubtype = {article} } The use of unmanned vehicles to perform tiring, hazardous, repetitive tasks, is becoming a reality out of the academy laboratories, getting more and more interest for several application fields from the industrial, to the civil, to the military contexts. In particular, these technologies appear quite promising when they employ several low-cost resource-constrained vehicles leveraging their coordination to perform complex tasks with efficiency, flexibility, and adaptation that are superior to those of a single agent (even if more instrumented). In this work, we study one of said applications, namely the visual tracking of an evader (target) by means of a fleet of autonomous aerial vehicles, with the specific aim of focusing on the target so as to perform an accurate position estimation while concurrently allowing a wide coverage over the monitored area so as to limit the probability of losing the target itself. These clearly conflicting objectives call for an optimization approach that is here developed: by considering both aforementioned aspects and the cooperative capabilities of the fleet, the designed algorithm allows controling in real time the single fields of view so as to counteract evasion maneuvers and maximize an overall performance index. The proposed strategy is discussed and finally assessed through the realistic Gazebo-ROS simulation framework. |

Marco Fabris; Angelo Cenedese Distributed Strategies for Dynamic Coverage with Limited Sensing Capabilities (Inproceedings) Mediterranean Conference on Control and Automation 2019 , 2019. (Abstract | BibTeX | Tags: coverage, multi-agent) @inproceedings{Fabris2019distributedstrategies, title = {Distributed Strategies for Dynamic Coverage with Limited Sensing Capabilities}, author = {Marco Fabris and Angelo Cenedese }, year = {2019}, date = {2019-07-03}, booktitle = { Mediterranean Conference on Control and Automation 2019 }, abstract = {In this work, it is presented the development of an efficient algorithm performing robotic coverage, clustering and dispatch around an event in static-obstacle-structured environments without relying on metric information. Specifically, the aim is to account for the trade-off between local communication given by bearing visibility sensors installed on each agent involved, optimal deployment in closed unknown scenarios and focus of a group of agents on one point of interest. The particular targets of this study can be summarized as 1. the computation, under certain topological assumptions, of a lower bound for the number of required agents, which are provided by a realistic geometric model (e.g. a round shape) to emphasize physical limitations; 2. the minimization of the number of nodes and links maintaining a distributed approach over a connected communication graph; 3. the identification of an activation cluster around an event with a radial decreasing intensity, sensed by each agent; 4. the attempt to send the agents belonging to the cluster towards the most intense point in the scenario by minimizing a weighted isoperimetric functional.}, keywords = {coverage, multi-agent}, pubstate = {published}, tppubtype = {inproceedings} } In this work, it is presented the development of an efficient algorithm performing robotic coverage, clustering and dispatch around an event in static-obstacle-structured environments without relying on metric information. Specifically, the aim is to account for the trade-off between local communication given by bearing visibility sensors installed on each agent involved, optimal deployment in closed unknown scenarios and focus of a group of agents on one point of interest. The particular targets of this study can be summarized as 1. the computation, under certain topological assumptions, of a lower bound for the number of required agents, which are provided by a realistic geometric model (e.g. a round shape) to emphasize physical limitations; 2. the minimization of the number of nodes and links maintaining a distributed approach over a connected communication graph; 3. the identification of an activation cluster around an event with a radial decreasing intensity, sensed by each agent; 4. the attempt to send the agents belonging to the cluster towards the most intense point in the scenario by minimizing a weighted isoperimetric functional. |

Marco Fabris; Angelo Cenedese; John Hauser Optimal Dynamic Formation Control for a Multi-Agent Linear System (Inproceedings) European Control Conference 2019, 2019. (Abstract | BibTeX | Tags: control, formation, multi-agent) @inproceedings{Fabris2019optimal, title = {Optimal Dynamic Formation Control for a Multi-Agent Linear System}, author = {Marco Fabris and Angelo Cenedese and John Hauser}, year = {2019}, date = {2019-06-28}, booktitle = {European Control Conference 2019}, abstract = {Given a multi-agent linear system, we formalize and solve a trajectory optimization problem that encapsulates trajectory tracking, distance-based formation control and input energy minimization. To this end, a numerical projection operator Newton’s method is developed to find a solution by the minimization of a cost functional able to capture all these different tasks. To stabilize the formation, a particular potential function has been designed, allowing to obtain specified geometrical configurations while the barycenter position and velocity of the system follows a desired trajectory.}, keywords = {control, formation, multi-agent}, pubstate = {published}, tppubtype = {inproceedings} } Given a multi-agent linear system, we formalize and solve a trajectory optimization problem that encapsulates trajectory tracking, distance-based formation control and input energy minimization. To this end, a numerical projection operator Newton’s method is developed to find a solution by the minimization of a cost functional able to capture all these different tasks. To stabilize the formation, a particular potential function has been designed, allowing to obtain specified geometrical configurations while the barycenter position and velocity of the system follows a desired trajectory. |

Giulia Michieletto; Angelo Cenedese; Antonio Franchi Bearing rigidity theory in SE(3) (Inproceedings) IEEE 55th Conference on Decision and Control (CDC), pp. 5950–5955, 2016, ISBN: 978-1-5090-1837-6. (Abstract | Links | BibTeX | Tags: formation, multi-agent, rigidity) @inproceedings{michieletto2016, title = {Bearing rigidity theory in SE(3)}, author = {Giulia Michieletto and Angelo Cenedese and Antonio Franchi}, url = {https://ieeexplore.ieee.org/document/7799182/}, doi = {10.1109/CDC.2016.7799182}, isbn = {978-1-5090-1837-6}, year = {2016}, date = {2016-01-01}, booktitle = {IEEE 55th Conference on Decision and Control (CDC)}, pages = {5950--5955}, abstract = {Rigidity theory has recently emerged as an efficient tool in the control field of coordinated multi-agent systems, such as multi-robot formations and UAVs swarms, which are characterized by sensing, communication and movement capabilities. This work aims at describing the rigidity properties for frameworks embedded in the three-dimensional Special Euclidean space SE(3) wherein each agent has 6DoF. In such a scenario, it is assumed that the devices are able to gather bearing measurements w.r.t. their neighbors, expressing them into their own body frame. The goal is then to identify the framework transformations that allow to preserve such measurements maintaining it rigid. Rigidity properties are mathematically formalized in this work which differs from the related literature as it faces the extension in three-dimensional space dealing with the 3D rotations manifold. In particular, the attention is focused on the infinitesimal SE(3)-rigidity for which a necessary and sufficient condition is provided.}, keywords = {formation, multi-agent, rigidity}, pubstate = {published}, tppubtype = {inproceedings} } Rigidity theory has recently emerged as an efficient tool in the control field of coordinated multi-agent systems, such as multi-robot formations and UAVs swarms, which are characterized by sensing, communication and movement capabilities. This work aims at describing the rigidity properties for frameworks embedded in the three-dimensional Special Euclidean space SE(3) wherein each agent has 6DoF. In such a scenario, it is assumed that the devices are able to gather bearing measurements w.r.t. their neighbors, expressing them into their own body frame. The goal is then to identify the framework transformations that allow to preserve such measurements maintaining it rigid. Rigidity properties are mathematically formalized in this work which differs from the related literature as it faces the extension in three-dimensional space dealing with the 3D rotations manifold. In particular, the attention is focused on the infinitesimal SE(3)-rigidity for which a necessary and sufficient condition is provided. |

Giuseppe Belgioioso; Angelo Cenedese; Giulia Michieletto Distributed partitioning strategies with visual optimization for camera network perimeter patrolling (Inproceedings) IEEE 55th Conference on Decision and Control (CDC), pp. 5912–5917, 2016, ISBN: 978-1-5090-1837-6. (Abstract | Links | BibTeX | Tags: camera networks, distributed solution, multi-agent, patrolling) @inproceedings{belgioioso2016, title = {Distributed partitioning strategies with visual optimization for camera network perimeter patrolling}, author = {Giuseppe Belgioioso and Angelo Cenedese and Giulia Michieletto}, url = {https://ieeexplore.ieee.org/document/7799179/}, doi = {10.1109/CDC.2016.7799179}, isbn = {978-1-5090-1837-6}, year = {2016}, date = {2016-01-01}, booktitle = {IEEE 55th Conference on Decision and Control (CDC)}, pages = {5912--5917}, abstract = {This work addresses the boundary patrolling problem, where a smart camera network undertakes the task of monitoring the perimeter of an environment so as to detect anomalies and track possible intrusions. Here, a distributed solution is sought based on the definition of a suitable functional that accounts both for the equitable partitioning of the available space and for the quality of vision of the patrolled area, and admits a unique optimal solution. The optimization of such functional leads to the design of an algorithm relying on a symmetric gossip communication protocol among the neighboring cameras. The theoretical results prove the correctness of the approach and the numerical simulations on a realistic scenario confirm its validity.}, keywords = {camera networks, distributed solution, multi-agent, patrolling}, pubstate = {published}, tppubtype = {inproceedings} } This work addresses the boundary patrolling problem, where a smart camera network undertakes the task of monitoring the perimeter of an environment so as to detect anomalies and track possible intrusions. Here, a distributed solution is sought based on the definition of a suitable functional that accounts both for the equitable partitioning of the available space and for the quality of vision of the patrolled area, and admits a unique optimal solution. The optimization of such functional leads to the design of an algorithm relying on a symmetric gossip communication protocol among the neighboring cameras. The theoretical results prove the correctness of the approach and the numerical simulations on a realistic scenario confirm its validity. |

Angelo Cenedese; Chiara Favaretto; Guido Occioni Multi-agent Swarm Control through Kuramoto Modeling (Inproceedings) 55th Conference on Decision and Control (CDC16), pp. 1820-1825, Las Vegas, NV, 2016, ISBN: 978-1-5090-1837-6, (DOI: 10.1109/CDC.2016.7798529 Electronic ISBN: 978-1-5090-1837-6 DVD ISBN: 978-1-5090-1844-4 Print on Demand(PoD) ISBN: 978-1-5090-1838-3). (Abstract | Links | BibTeX | Tags: formation, Kuramoto, multi-agent, synchronization, UAVs) @inproceedings{NnAaaah, title = {Multi-agent Swarm Control through Kuramoto Modeling}, author = {Angelo Cenedese and Chiara Favaretto and Guido Occioni}, url = {https://ieeexplore.ieee.org/document/7798529/}, doi = {10.1109/CDC.2016.7798529}, isbn = {978-1-5090-1837-6}, year = {2016}, date = {2016-01-01}, booktitle = {55th Conference on Decision and Control (CDC16)}, pages = {1820-1825}, address = {Las Vegas, NV}, abstract = {In this paper we discuss a particular case of synchronization involving a finite population of nonlinearly coupled oscillators. We employ a discrete time approximation of the Kuramoto model in order to achieve the coordination of the heading directions of N identical vehicles moving at a constant speed in a 2D environment; this model acts as a base for a more complex distributed control, the aim of which is to direct the vehicles towards a target, adjusting their trajectories alongside their formation in the process, while avoiding collisions.}, note = {DOI: 10.1109/CDC.2016.7798529 Electronic ISBN: 978-1-5090-1837-6 DVD ISBN: 978-1-5090-1844-4 Print on Demand(PoD) ISBN: 978-1-5090-1838-3}, keywords = {formation, Kuramoto, multi-agent, synchronization, UAVs}, pubstate = {published}, tppubtype = {inproceedings} } In this paper we discuss a particular case of synchronization involving a finite population of nonlinearly coupled oscillators. We employ a discrete time approximation of the Kuramoto model in order to achieve the coordination of the heading directions of N identical vehicles moving at a constant speed in a 2D environment; this model acts as a base for a more complex distributed control, the aim of which is to direct the vehicles towards a target, adjusting their trajectories alongside their formation in the process, while avoiding collisions. |

# List of Publications

Cooperative Optimization of UAVs Formation Visual Tracking (Journal Article) Robotics, 8 (3), pp. 1–22, 2019. |

Distributed Strategies for Dynamic Coverage with Limited Sensing Capabilities (Inproceedings) Mediterranean Conference on Control and Automation 2019 , 2019. |

Optimal Dynamic Formation Control for a Multi-Agent Linear System (Inproceedings) European Control Conference 2019, 2019. |

Bearing rigidity theory in SE(3) (Inproceedings) IEEE 55th Conference on Decision and Control (CDC), pp. 5950–5955, 2016, ISBN: 978-1-5090-1837-6. |

Distributed partitioning strategies with visual optimization for camera network perimeter patrolling (Inproceedings) IEEE 55th Conference on Decision and Control (CDC), pp. 5912–5917, 2016, ISBN: 978-1-5090-1837-6. |

Multi-agent Swarm Control through Kuramoto Modeling (Inproceedings) 55th Conference on Decision and Control (CDC16), pp. 1820-1825, Las Vegas, NV, 2016, ISBN: 978-1-5090-1837-6, (DOI: 10.1109/CDC.2016.7798529 Electronic ISBN: 978-1-5090-1837-6 DVD ISBN: 978-1-5090-1844-4 Print on Demand(PoD) ISBN: 978-1-5090-1838-3). |