Vibration suppression of plate using linear MR fluid passive damper

In order to suppress vibrations of large flexible structures such as aircraft wings, a damper will be applicable. Since eigenfrequencies of an aircraft wing are small, it requires the following for the damper: (1) The damping force have to be large for low frequency because the vibration frequency of the wing is small. (2) it works for small displacement, (3) its size has to be small which can be stacked in the wing, and (4) passive damper is desirable because the maintenance has to be free in the damper. This article presents a new type linear damper, which satisfies the conditions as just mentioned. The damper consists of a number of thin plates with slits. MR fluid is filled in the damper, so that magnetic fields freeze MR fluid. Resisting torque (shearing torque) is generated when the plates slide due to the shear of slits of the plates. The damper works against the bending moment of the wing by responding its deflection. The damper is maintenance free, and it is one of passive dampers with a good durability.