Improvement of flight simulator feeling using adaptive fuzzy backlash compensation

In this paper we addressed the problem of improving the control of DC motors used for the specific application of a 3 degrees of freedom moving base flight simulator. Indeed the presence of backlash in DC motors gearboxes induces shocks and naturally limits the flight feeling. In this paper, dynamic inversion with Fuzzy Logic is used to design an adaptive backlash compensator. The classification property of fuzzy logic techniques makes them a natural candidate for the rejection of errors induced by the backlash. A tuning algorithm is given for the fuzzy logic parameters, so that the output backlash compensation scheme becomes adaptive. The fuzzy backlash compensator is first validated using a realistic model of the mechanical system and is actually tested on the real flight simulator

Control of a new kind of moving base flight simulator

In this paper we addressed the problem of improving the control of DC motors used for the specific application of a 3 degrees of freedom moving base flight simulator. Indeed the presence of backlash in DC motors gearboxes naturally limits the flight feeling. The proposed solution consists to demonstrate that artificial neural networks can be used to compensate hysteresis caused by gear backlash in precision positioncontrolled mechanisms. A major contribution of this research is that physical analysis of the system nonlinearities and optimal control are used to design the neural network structure. The results obtained by simulation, using this reduced size neural controller, are very encouraging. This method is actually tested on the real prototype, and the first observed results are very promising

Adaptive fuzzy backlash compensation for a new dynamic flight simulator

In this paper we addressed the problem of improving the control of DC motors used for the specific application of 3 degrees of freedom moving base flight simulator. Indeed the presence of backlash in DC motors gearboxes induces shocks and naturally limits the flight feeling. In this paper, dynamic inversion with Fuzzy Logic is used to design an adaptive backlash compensator. The classification property of fuzzy logic techniques makes them a natural candidate for the rejection of errors induced by the backlash. A tuning algorithm is given for the fuzzy logic parameters, so that the output backlash compensation scheme becomes adaptive. The fuzzy backlash compensator is first validated using a realistic model of the mechanical system and is actually tested on the real flight simulator

Enhancing the flight simulator feelings by a minimising backlash-effects process

In this paper we addressed the problem of improving the control of AC motors used for the specific application of 3 degrees of freedom moving base flight simulator. Indeed the presence of backlash in DC motors gearboxes induces shocks and naturally limits the flight feeling. A comparison is hence set up between two techniques aiming to deal with this problem: Adaptive Fuzzy Controller and Neural Controller. Dynamic inversion with Fuzzy Logic is used to design an adaptive backlash compensator. The classification property of fuzzy logic techniques makes them a natural candidate for the rejection of errors induced by the backlash. A tuning algorithm is given for the fuzzy logic parameters, so that the output backlash compensation scheme becomes adaptive. The compensator uses the Neural Networks techniques demonstrate that artificial neural networks can be used to compensate hysteresis caused by gear backlash in precision position-controlled mechanisms. A major contribution of this research is that physical analysis of the system nonlinearities and optimal control are used to design the neural network structure

Etude comparative des scores d'implication des salariés syndiqués et non syndiqués en France

International audienceEtude comparative des scores d’implication des salariés syndiqués et non syndiqués en France.</p

Case of Massive Hydatid Pulmonary Embolism Incidentally Discovered in a 56-Year-Old Woman with Posttraumatic Abdominal Pain

Hydatid pulmonary embolism rarely occurs. It arises from the rupture of a hydatid heart cyst or the opening of a visceral hydatid cyst into the venous circulation. We report a case with pulmonary hydatidosis resulting in a massive bilateral pulmonary embolism in a 56-year-old woman with history of hepatic echinococcosis. A brief overview of clinical features and radiologic findings is presented