Design of a new magneto-rheological damper featuring a hybrid type of piston for lower limb exoskeleton

In this paper, a new magneto-rheological MR) fluid damper is proposed to achieve lower limb exoskeleton of the rehabilitation device. This is achieved by designing the piston configuration as both a square geometry and a circular geometry. By doing this, controllability of the both vibration and moment in the horizontal axis can be obtained. In the design process, two operation modes of MR fluid including flow mode and shear mode are used and the principal design parameters of the square piston are optimized to have low limb exoskeleton as possible under imposed design constraints such as size. This principle is also applied for the circular piston. In addition, the configuration parameters of the design are obtained by optimization using a commercial software as ANSYS ADPL. It is shown through computer simulations that the requirements of the force associated with the limb exoskeleton are successful achieved.