Libero Paolucci

Next generation of smart sensorless drives for sustainable underwater vehicles

Both Autonomous and Remotely Operated Underwater Vehicle play a key role in the development of offshore industrial installations assuring both cost and safety improvements in a very harsh environment. In order to improve performances, reliability and sustainability of underwater robotics, there is the need of a new generation of motors and drives devoted to this kind of applications. In this work authors focus their attention to most interesting aspect of the development of this new generation of products, introducing design examples and results of experimental activities performed on motors installed on Tifone, Marta and Feel Hippo AUVs.

Design and testing of a pulley and cable actuator for large ball valves

The objective of this work is the development of an innovative actuator for Velan ABV S.p.A., which is mainly used for control and special on/off applications where high efficiency and linear behaviors are desirable specifications. The main performances of the proposed actuator, which has been protected by a patent, have been compared with a conventional scotch yoke one, using both the simulation results and the experimental data. In order to measure the efficiency and the dynamical response of the actuators, the authors have designed a hydraulic test rig, configured to fulfill different testing procedures. In this way, it is possible to perform both static tests to identify actuator efficiency and dynamic hardware-in-the-loop tests in which an assigned load or valve impedance function is simulated to verify the response of the tested object in realistic operating conditions. Finally, the proposed test rig has been successfully used to perform reliability and fatigue tests in which the actuator is stressed with realistic and repetitive loads. Moreover, the integrated development of both innovative actuator and testing devices is explained introducing interesting concepts whose applications are normally limited to robotics (e.g. impedance and force control) or vehicular technology (e.g. smart suspensions and suppression of vibrations).

Development of sensorless PM servo-system for harsh environments

Aim of this work is the development of efficient and robust filters for speed and position controls to be operated in harsh environments and in particular for underwater applications. PM motors are the most commonly adopted solutions for this kind of applications where the reliability of the component has important consequences both for the safety of the vehicle and the sustainability of the application. Common applications are the inspections of valuable underwater sites or the maintenance of potentially dangerous industrial facilities such as submerged plants of Oil&Gas industry. In particular in this work authors have concentrated their attention on the part concerning robust and efficient speed and position estimators for sensorless drive systems.