Frontal Crash Mitigation using MR Impact Damper for Controllable Bumper

This study presents performance characteristics of a magnetorheological (MR) impact damper for controllable bumper in vehicle systems. Recently, several mechanisms are proposed in order to minimize the injury of vehicle occupants during frontal collision. One of the promising candidates is the MR fluid which undergoes significant instantaneous reversible changes in material characteristics when subjected to a magnetic field. Using this salient property, a new type of MR impact damper is devised in this work. The proposed damper is integrated with bellows to induce the flow motion and the motion is operated under flow mode. The field-dependent damping force is evaluated by computer simulation with various conditions. In order to investigate the effectiveness of the proposed impact damper, a lumped parameter mathematical model of frontal vehicle crash system including MR impact damper is developed and realized in order to evaluate acceleration peak reductions and transmitted force in the frontal collision.