A controllable magneto-rheological device includes an annular cylinder (70) formed by inner (72) and outer (74) walls connected at first and second opposing ends and forming an inner shaft (76) configured to receive an operational component of an engine, generator or other device including one or more rotating structures. A magneto-rheological fluid (78) is provided to fill a volume between the inner and outer walls of the annular cylinder. A plurality of electro-magnetic coils (80) are positioned around the outer wall of the annular cylinder. One or more current controllers (88) are coupled to the plurality of electro-magnetic coils for introducing a current through each of the electro-magnetic coils and corresponding magnetic flux through the magneto-rheological fluid. A level of currentprovided to each of the plurality of electro-magnetic coils directly affects the viscosity of the magneto-rheological fluid and thus the stiffness and damping levels of the controllable magneto-rheological device.