Force Tracking Control of Vehicle Vibration with MR-Dampers

A semi-active force tracking control strategy is formulated to realize variable and asymmetric damping of an MR damper. A modified "on-off" control law is devised using an inverse model of a MR-damper incorporating hysteretic damping properties. An asymmetric current and thus force generating algorithm is further developed and integrated within the controller to realize asymmetric damping properties in a continuous manner from the symmetric damper design. The performance characteristics of the proposed force-tracking semi-active control are evaluated to study the ride vibration attenuation of a quarter-vehicle model using different damper force gains. The ride performance potentials of the proposed semi-active MR-suspension system are further evaluated under varying vehicle loads and speeds under harmonic excitations in the 0.5-15 Hz range. The results show that the MR-damper with proposed semi-active force tracking control could track the target force reasonably well in a continuous manner and provide improve attenuation of road-induced vibration