Semi active control of fighter jet vibrations using different control methods with magneto-rheological damper

Aircraft landing gears are subjected to vibrations during the landing and taxi position. This can affect passenger health. Landing gears are used to terminate that can occur negative effects. In addition to this comfort expectation increased depending upon advance of technology as time progressed. Therefore, a lot of researches have been made to developed the most efficient landing gear from the point of passenger safety and comfort and still, they are continued. Passive, semi active and active landing gears are used to reduce vibrations. The most efficient system is active landing gears for vibration attenuation. But semi active landing gears are preferred because of has similar performance and low cost in comparison with active landing gears. In this study a ten degrees of freedom fighter jet is modelled for taxi position and MR (Magneto-Rheological) damper is used for semi active control. There is used two separate mathematical model; firs model: aircraft landing gears equipped with MR damper and second model: aircraft seats equipped with MR damper. Modified Bouc-Wen model is used as MR damper model. System was firstly modelled as passive model and after that it is modelled with using MR dampers instead of passive absorbers. Uncontrolled 0 V MR damper situation is compared with passive system and it is proved that is suitable for safety. Then for the first model, fuzzy logic control (FLC) and PID control is used in controlling the system. For the second model, linear matrix inequality (LMI) based state feed-back H_∞ control is implemented. Modeling and simulation study is achieved via MATLAB-Simulink program. YALMIP solver software is used in designing H_∞ controller. It is shown that positive performance of semi active control in reducing of exposed to vibrations of fuselage and pilots. Thus, it is compared with results of different control methods.