Application of magneto-rheological (MR) damper in landing gear shimmy

In order to study the semi-active control of landing gear shimmy, expressions of MR damper equivalent damping coefficient with voltage and amplitude was set up firstly. And then, the mathematical model for semi-active control of landing gear shimmy was constructed and maximum energy dissipation approach based on MR was proposed to suppress shimmy. Finally, the critical shimmy velocity varying with the vertical force during taxiing was investigated in different caster lengths. The simulation results show that the performance of MR to suppress shimmy is greatly superior to hydraulic shimmy damper during taxiing, and MR not only suppresses shimmy completely but also exhibits good robustness about some system parameters.