Research On Landing Control Algorithm Of MR Damper And Driving Current Source

Magnetorheological(MR) fluid damper has many advantages such as simple structure,fast transient response, low energy consumption, high reliability and widely adjustable damping force. It has been found effective in vehicle shock system, windbreak and antiquake building, offshore platform damping, etc. It also has a bright application future when used in aircraft landing gear damping system. Issues such as impact model, current source and controller design when landing gear utilizes MR fluid damper are discussed and researched in this report.First of all, for formerly designed multi-ring groove structure MR damper, a mechanics modal is established according to rheological dynamics. Further, an aircraft landing gear dynamics model used for Matlab simulation is proposed. For different body weight and vertical landing velocity, the relationships between the excitation current and the parameters such as vibration amplitude, frequency and settling time, are obtained. Simulation results show that the landing gear vibration parameters can be conveniently controlled via a proper control current, and a good dynamic performance can be achieved.Then, based on Amtega16, current source is suitable for MR fluid damper used in landing gear, which can provide continously adjustable, high accurate regulating load current.Finally, a fuzzy controller is designed, which the current is continuously and real-timely adjustable. The controller can effectively control the landing gear by the real-time damping force produced through adjusting the current of the MR damper coil and then the magnetic field of the MR damper. The Matlab simulation indicates that compared with open-loop control, the fuzzy control algorithm based on MR damper is more effective and can obviously restrain the speed response of the structure. When used in landing gear damping system, this damper can greatly improve the safety and comfort of the aircraft.