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This paper presents a novel weather-routing system based on a multi-criteria setup. The set of 3 conflicting criteria is: travel time, ship navigation added resistance (caused by wind and waves), and navigation risk/safety. To this aim, the International Maritime Organization (IMO) safety guidelines are exploited for the design of navigation risk criterion as a function of the METeorological and OCeanographic (METOC) and sailing conditions. This risk is directly integrated into the multi-criteria setup, as an innovative alternative to the systems proposed in the open literature. The proposed methodology is tested in a real operational scenario in the Mediterranean Sea. The obtained results show how the proposed system provides alternative routes with minimum risk to the decision-makers, as well as other different alternative routes minimizing the other criteria.

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This paper presents a cooperative and distributed control law for multiple Autonomous Underwater Vehicles (AUVs) executing a mission while meeting mutual communication constraints. Virtual couplings define interaction control forces between neighbouring vehicles. Moreover, the couplings are designed to enforce a desired vehicle-vehicle and vehicle-target spacing. The whole network is modelled in the passive, energy-based, port-Hamiltonian framework. Such framework allows to prove closed-loop stability using the whole system kinetic and virtual potential energy by constructing a suitable Lyapunov function. Furthermore, the robustness to communication delays is also demonstrated. Simulation results are given to illustrate the effectiveness of the proposed approach

This work proposes a game theoretic approach to tackle the problem of multi-robot coordination in critical scenarios where communication is limited and the robots must accomplish different tasks simultaneously. An important application falls in underwater robotic framework where robots are used to protect a ship against asymmetric threats guaranteeing simultaneously the coverage of the area around the ship and the tracking of a possible intruder. The problem is modelled as a potential game for which novel learning protocols are introduced. Indeed, a general extension of pay-off based algorithms is herein proposed where the main difference with state-of-the-art protocols is that the trajectory optimization is considered instead of single action optimization. Moreover, the proposed T-algorithms, steer the robots toward Nash equilibria that will be shown to correspond to the accomplishment of different, possibly antagonistic, goals. Finally, performances of the algorithms, under different scenarios, have been evaluated in simulations

This paper presents a cooperative, distance-based, distributed control law for multiple Autonomous Underwater Vehicles (AUVs) executing a mission while meeting mutual communications constraints. The classic graph theory provides the essential tools to model the whole network of interacting robots, which is then handled within the energy-based, port-Hamiltonian framework. The virtual interaction forces generated over each link are represented by visco-elastic couplings. The passivity theory allows the construction of a Lyapunov function for the closed loop system to demonstrate the stability in large of the whole network with the synthesized control law. Moreover, always using passivity-based techniques, the behaviour of the group is made as flexible as possible with arbitrary split and join events. Several software simulations, involving a team or sub-teams of agents that perform typical missions in marine environment, show the effectiveness of the proposed approach

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