Advanced vehicular technologies including hybridization have been identified as the
focuses of the University of Toledo University Transportation Center (UT-UTC) in the
effort to increase fuel efficiency and reduce polluting emissions. The proven advantages
of the hybrid vehicles or variable cylinder management also comes with challenging
problem of noise, vibration and harshness (NVH). This issue has to be properly addressed
in order for the technologies to quickly enter the market or be widely applied.
The NVH in hybrid and alternative power-train vehicles is not conventional since
it involves multiple power sources working in different modes and the switching among
them. This feature results in vibration in all forms containing shock and harmonic
vibration in very wide range of frequencies and random excitations as well. It has
been proven that the passive vibration isolators, e.g. elastomeric and hydraulic,
are not effective in modern vehicles. Active mounts such as the one installed in the
Honda Odyssey are effective in all conditions, but they are expensive and can lead
to stability problems. Research has shown that the semi-active devices are preferred
thanks to their effectiveness and affordability.
In the previous phases, the research team has completed design, analytical model and
fabrication of a single-axis semi-active magnetorheological (MR) fluid mount for vibration
isolation in hybrid vehicles. The experimental evaluation of the mount proved the efficacy of the mount is adapting
to different operation conditions. In the current phase, control systems have been designed for this MR fluid mount.
Currently these controllers are being evaluated using computer simulation. The controller is designed to achieve and maintain low vibration transmissibility
in the mount. This is the main requirement for the mount to mitigate the vibration
issue in different operation conditions of the vehicle. This proposal is focused on conducting experimental evaluation of the controller for
the MR mount. This is the final step in developing this innovative vibration isolation device. The
controller will have adaptive and optimal characteristics so that the mount will be
able to respond quickly and efficiently in all possible conditions of the operation
of the vehicle. This way the mount will provide a controlled shock and vibration isolation
with minimal use of energy. This stage will make the mount ready forvehicle testing
and possible adaptation for hybrid vehicles.
The evaluation and modification of the controller by experiments will complete the
semiactive MR mount design and make it ready for commercialization. The unique and
innovative mount, together with its intelligent control, will solve the NVH problem
induced by the power-generating components and speed up the commercialization process
of the advanced vehicular technologies.