Hydraulic hybrid vehicle vibration isolation control with magnetorheological fluid mounts

Hydraulic Hybrid Vehicle (HHV) is an emerging technology especially for heavy-duty vehicles, thanks to its high efficiency and power density. However, one of the main problems that should be solved to enable the successful commercialisation of HHV is the excessive noise and vibration involved with hydraulic systems. This study focuses on using the magnetorheological fluid (MRF) technology to reduce the noise and vibration transmissibility from the power sources to the vehicle body. To study the noise and vibration of HHVs, a HHV structure in parallel design was analysed. An MRF mount, to use for the engine and pump/motor, was designed, fabricated and tested. Vibration control schemes based on the skyhook algorithm were utilised to reduce the transmissibility and amplitudes of vibration. The research showed that the MRF mounts played an important role in reducing the noise and vibration transmitted to the vehicle body. Additionally, the locations and orientations of the isolation system affected the efficiency of the noise and vibration mitigation.