Displacement and Force Control of a Quarter Car Using a Mixed Mode MR Mount

Abstract

In hydraulic hybrid vehicles (HHV), vibration in dual-mode pump/motor units should be isolated from the chassis. A mixed mode magnetorheological (MR) fluid mount was adopted to isolate this vibration and was evaluated in a quarter car model. The MR fluid mount was designed to be able to operate in flow mode and squeeze mode independently and simultaneously. For HHVs, it is desirable to control force and displacement transmissibility. These simulation results presented a basis for designing an effective algorithm to control both the displacement transmissibility and force transmissibility. Moreover, a hierarchical controller for minimizing the two requirements for transmissibility was also constructed. At last, a fuzzy logic controller was devised to closely reproduce the effect of the hierarchical controller. The experiments were set up to facilitate the hardware-in-the-loop evaluation of the mount. Results from the experiments showed that the mixed mode MR fluid mount was able to achieve desired dynamic stiffness profile to minimize the dual-transmissibility criterion.