Magnetorheological (MR) fluid consists of iron particles suspended in oil, and its behavior can be controlled by applying a magnetic field.
The MR rotary actuator uses the shear mode of MR fluid to control resistance to shaft rotation or torque, generating haptic sensations. By leveraging the properties of MR fluid, this actuator can provide both vibrotactile and kinesthetic feedback through voltage input.
The figure shows the MR Haptic module, consisting of the MR dial, encoder, knob, and casing. The encoder and MR dial are connected with a 1:1 gear ratio to track rotation, enabling the virtual dial to accurately mirror real-world movement.