Control of Landing Efficiency of an Aircraft Landing Gear System With Magnetorheological Dampers

In this research, a two-core type of a semi-active magnetorheological (MR) damper is designed for an airplane landing gear system, and its landing efficiency is evaluated using two different controllers. Firstly, MR damper is designed on the basis of dynamic properties of a commercial oleo-pneumatic passive damper. To satisfy the fail-safe condition of MR damper, two orifices are used to provide asymmetry properties via a recoil valve. Second, in order to evaluate the landing efficiency, the equation of motion of a landing gear model with MR damper is derived, and two different controllers are formulated: a skyhook controller and a hybrid controller, which is featured by both the skyhook and force control actions. It is shown through computer simulations that the landing efficiency of the hybrid controller is much better than the conventional skyhook controller.