@article{GENERAL,
      recid = {7717},
      author = {Bibuli, M and Bruzzone, Ga and Bruzzone, Gi and Caccia, M  and Camporeale, G and Chiarella, D and Ferretti, R and  Giacopelli, M and Odetti, A and Ranieri, A and Spirandelli,  E and Zereik, E},
      title = {An Advanced Guidance & Control System for an Unmanned  Vessel with Azimuthal Thrusters},
      journal = {Conference Proceedings of iSCSS},
      address = {2018-10-02},
      number = {GENERAL},
      abstract = {The proposed paper presents the design and development of  the combined guidance & control strategies for the  autonomous navigation of an unmanned vessel characterized  by azimuth-based thrust architecture. Autonomous Marine  Vehicles (AMVs) are consolidates technological tools  commonly employed for different tasks such as exploration,  sampling and intervention. With the final aim of autonomous  shipping, the capabilities of AMVs have to be migrated and  adapted towards the reliable and safe control of  commercial-like unmanned vessel, that are taking place  thanks to a number of technological research projects. The  employment of new concept hulls and thrust configurations,  as for instance Small Waterplane Area Twin Hull (SWATH)  combined with Azimuthal propulsion (common propeller-based  thruster with the capability of 360◦ rotation around the  vertical axis), requires robust guidance techniques to  provide precise and reliable motion control during  navigation. The paper proposes a dual-loop guidance &  control scheme able to provide advanced navigation  capabilities. In particular, the inner control loop,  devoted to the actuation of the azimuthal thrusters, allows  the tracking of reference course angle (namely the  autopilot). Such a control loop is characterized by a  modified PID regulation scheme, where a novel adaptive  derivative component is inserted in order to improve the  convergence curve towards the required course reference.  The outer guidance loop, based on Lyapunov/virtual-target  approach, allows the vessel to track generic desired paths,  thus enhancing the autonomous navigation capabilities also  in constrained environments. The paper will provide a deep  design & analysis approach for the developed  techniques, as well as simulation results of the combined  guidance & control scheme, proving the reliability of  the proposed approach in different operative conditions.  Experimental results will be provided, depending on the  availability of the actual autonomous vessel (currently  under final development/test phases and related to the  specific project activities). },
      url = {http://library.imarest.org/record/7717},
}