Abstract: A variable stiffness suspension bushing (18) for use in a suspension of a motor vehicle comprises a shaft or rod (40) connected to a suspension member (12), an inner cylinder (42) fixedly connected to the shaft or rod (40), and an outer cylinder (44) fixedly connected to a chassis member (16). A magnetorheological (MR) elastomer (48), having iron particles embedded therein, is interposed between the inner (42) and outer (44) cylinders, and a coil (54) is disposed about the inner cylinder (42). When the coil (54) is energized by electrical current provided from a suspension control module (20), a variable magnetic field is generated so as to influence the magnetorheological (MR) elastomer (48) whereby variable stiffness values of the elastomer (48) are obtained to provide the bushing (18) with variable stiffness characteristics in order to eliminate compromises heretofore necessary when using single, fixed rate bushings.

Abstract: Method and apparatus for maintaining vehicular ride height in a vehicle having a body, front and rear wheels and an air suspension including front and rear air springs. The method includes sensing vehicle body height relative to the wheels to obtain front and rear vehicle height signals, and sensing vehicle speed to obtain a vehicle speed signal. The method also includes processing the front height signals to obtain a vehicle roll signal that has been compensated for the natural lean of the vehicle, the vehicle roll signal indicating vehicle roll due to steering adjustments by the vehicle operator. The method further includes processing the vehicle speed signal to obtain a vehicle pitch offset signal, indicating vehicle body height change due to longitudinal vehicle acceleration. The method also includes adjusting the height of the vehicle toward a predetermined target ride height based on the vehicle height sensor signals which have been compensated for vehicle roll and pitch.