Fast Response MR-Fluid Actuator

Magnetorheological (MR) fluids are materials that change their rheological behavior upon applying a magnetic field. They have been promising as functional fluids that can improve the properties of mechanical systems. We have developed an actuator using MR fluid. In the previous paper, a method of designing MR-fluid actuators was proposed on the basis of magnetic circuit theory. The basic experiments were carried out and static properties that agreed well with the design were obtained. However, the transient response, which was not considered in the design phase, was not very fast. In this study, we investigate the dynamics of the MR-fluid actuator and aim to improve the response. The transient magnetic analysis is examined in consideration of the eddy current. Two approaches to improving the response are proposed. Finally, we realize a much faster MR-fluid actuator.