Structure Design Of Rotary Plate Magnetorheological Shimmy Damper And Experimental Research

According to the technical requirements of a certain UAV for shimmy damper,a rotary plate magnetorheological shimmy damper based on the working mode of pressure-shearing is designed,to explore the feasibility of using magnetorheological shimmy dampers instead of hydraulic shimmy dampers,aiming to solve the problem that wheel deflection appears asymmetry in neutral position under the long-term action of alternating load,but the damping characteristics can not be changed independently,so as to suppress the phenomenon of front wheel shimmy more effectively.The design of this paper mainly starts from the two aspects of structure and magnetic circuit.Firstly,the magnetic circuit simulation and structural parameter optimization are carried out by using ANSYS software,so as to improve the magnetization effect and make the structure more reasonable.Then the moment model is constructed,and the strength check is carried out on the dangerous section of key components.Finally,the drawing is designed by using CAD and CATIA software.The MRF damper and its transmission structure are processed,assembled,debugged and experimented.To enhance the performance,this rotary plate shimmy damper has the following characteristics: 1,The damping gap is adjustable,which can match the damping torque range suitably;2,The throttle structure with groove can enhance magnetizing effect,increase the adjustable damping torque;3,The flexible sealing structure.The sealing property of structure and assembly process are taken into account.The performance of the shimmy damper is tested in a constant current mode(i.e.the input current is a constant current for loading).The experiments are carried out under the working conditions of different amplitude(1~5mm)and frequency(1~20Hz)according to a current gradient.Comparing the collected data with the original hydraulic shimmy damper,the results show that the range of damping force of the magnetorheological damper can cover the damping force of the hydraulic shimmy damper under the corresponding working conditions.It can replace the function of hydraulic shimmy damper in terms of swing-reducing performance.The ADAMS software is used to simulate the overall dynamics,which the shimmy damper is stalled on the landing gear.The shimmy of the wheel is analyzed by simulating the speed of the skimming at various stages,such as the convergence of thependulum angle and the return neutrality.The results show that the adjustment range of the damping torque covers the best torque reduction torque under various speeds,and it is feasible in terms of overall compatibility.