Development and characterization of a novel rotary magnetorheological fluid damper with variable damping and stiffness

Abstract

A novel compact rotary magneto-rheological (MR) damper with variable damping and stiffness has been proposed and analyzed. Its variable damping is generated by tuning yield stress of MR fluid in both pre-yield and post-yield regimes. The controllable storage modulus in pre-yield region of MR fluid is used to achieve magnetic field dependent stiffness. To ensure the MR rotary damper output variable stiffness in large angle, a unique structure that contains two driven disks and an active rotary disk is proposed. The effects of current, angle and frequency on the torque–angle loops and torque-frequency loops have been investigated experimentally. Adaptive network based fuzzy inference system with learning ability is adapted to capture the non-linear behaviors of variable damping and stiffness. By comparing with the MR dampers with one driven disk and that with no driven disk, it can be found that the proposed MR rotary damper with two driven disks can provide variable stiffness in larger angle. The results made the concept of proposed damper with variable damping and stiffness become feasible.