A center bearing assembly rotatably supports an intermediate portion of a vehicle
driveshaft assembly during use. The center bearing assembly includes a rigid bracket
that is secured to a support surface of the vehicle, a support member that is supported
within the rigid bracket, and an annular bearing that is supported within the support
member for rotatably supporting the intermediate portion of the vehicle driveshaft
assembly. The support member is formed from a resilient material and has a cavity
formed therein. A sponge is disposed within the cavity formed in the support member.
The sponge may be formed from any material that is capable of absorbing or otherwise
retaining a quantity of a rheological fluid therein. A control circuit is provided
for selectively generating and applying an energy field to the Theological fluid
contained within the sponge and thereby varying the resistance to flow or shear
thereof. As a result, the vibration dampening characteristics of the support member
can be varied.