Abstract: A variable power steering system for a motor vehicle is responsive to an activity signal from a vehicle stability enhancement (VSE) system and a lateral surface coefficient of friction estimator to modify steering assist in an amount dependent on the estimated surface coefficient when the vehicle stability enhancement system is active. The modification is phased in and out with slew limiting in steps also determined by the estimated lateral surface coefficient, with both the maximum modification and the step size varying inversely with lateral surface coefficient. The system preferably determines offset current values for the VSE system and estimated lateral acceleration, as well as for any other vehicle traction limit handling systems such as anti-lock braking (ABS) or traction control (TCS) and chooses the greatest in magnitude as a road surface adaptation offset current for addition to a vehicle speed offset current to provide a total current signal for the modification.

Abstract: A variable power steering system for a motor vehicle is responsive to an activity signal from a vehicle stability enhancement (VSE) system and a lateral surface coefficient of friction estimator to modify steering assist in an amount dependent on the estimated surface coefficient when the vehicle stability enhancement system is active. The modification is phased in and out with slew limiting in steps also determined by the estimated lateral surface coefficient, with both the maximum modification and the step size varying inversely with lateral surface coefficient. The system preferably determines offset current values for the VSE system and estimated lateral acceleration, as well as for any other vehicle traction limit handling systems such as anti-lock braking (ABS) or traction control (TCS) and chooses the greatest in magnitude as a road surface adaptation offset current for addition to a vehicle speed offset current to provide a total current signal for the modification.

Abstract: A motor vehicle has a body supported on a front pair of wheels and a rear pair of wheels with front suspension apparatus providing controllable vertical wheel constraint and roll stiffness and a rear pair of wheels with rear suspension apparatus providing controllable vertical wheel constraint and rear roll stiffness. Responsive to a commanded vehicle acceleration or braking, the driven wheel (acceleration) or front (braking) suspension apparatus is briefly altered to provide optimal tire patch traction for the one of the pair of wheels. The alteration may be further responsive to vehicle speed and/or lateral acceleration. The controllable part of the suspension apparatus may be dampers, springs or anti-sway apparatus such as torsion bars. If anti-sway apparatus, the front and/or rear roll stiffness may be controlled to promote oversteer at low vehicle speed and understeer at high vehicle speed.

Abstract: A rear wheel steering control determines, when desired and actual lateral accelerations of a vehicle have the same direction, an instantaneous dynamic yaw center on a vehicle longitudinal axis in response to the measured vehicle speed. It further determines a cornering radius and an instantaneous Ackerman center as a point at the outer end of the cornering radius extended outward perpendicular to the vehicle longitudinal axis from the instantaneous Ackerman center. The control then directs a rear wheel of the vehicle to be perpendicular to a line connecting the instantaneous Ackerman center to the center of the wheel. The dynamic yaw center, and thus the instantaneous Ackerman center, is preferably shifted rearward with increasing vehicle speed to shift vehicle steering in a direction from oversteer at very low speeds for greater ease of steering in parking maneuvers to understeer for vehicle stability in high speed driving conditions.

Abstract: A rear wheel steering control determines, when desired and actual lateral accelerations of a vehicle have the same direction, an instantaneous dynamic yaw center on a vehicle longitudinal axis in response to the measured vehicle speed. It further determines a cornering radius and an instantaneous Ackerman center as a point at the outer end of the cornering radius extended outward perpendicular to the vehicle longitudinal axis from the instantaneous Ackerman center. The control then directs a rear wheel of the vehicle to be perpendicular to a line connecting the instantaneous Ackerman center to the center of the wheel. The dynamic yaw center, and thus the instantaneous Ackerman center, is preferably shifted rearward with increasing vehicle speed to shift vehicle steering in a direction from oversteer at very low speeds for greater ease of steering in parking maneuvers to understeer for vehicle stability in high speed driving conditions.

Abstract: A motor vehicle has a body supported on a front pair of wheels and a rear pair of wheels with front suspension apparatus providing controllable vertical wheel constraint and roll stiffness and a rear pair of wheels with rear suspension apparatus providing controllable vertical wheel constraint and rear roll stiffness. Responsive to a commanded vehicle acceleration or braking, the driven wheel (acceleration) or front (braking) suspension apparatus is briefly altered to provide optimal tire patch traction for the one of the pair of wheels. The alteration may be further responsive to vehicle speed and/or lateral acceleration. The controllable part of the suspension apparatus may be dampers, springs or anti-sway apparatus such as torsion bars. If anti-sway apparatus, the front and/or rear roll stiffness may be controlled to promote oversteer at low vehicle speed and understeer at high vehicle speed.

Abstract: A vehicle suspension control includes a vehicle body control responsive to body/wheel velocity at the corners of the vehicle body to derive a demand force command for dampers at each corner of the vehicle body for vehicle body control and applies each of the derived demand force commands to its respective damper only when a comparison of the direction of the demand force command with the sensed relative velocity of the damper indicates that a force corresponding to the demand force command can be effectively exerted by the damper. But the suspension control also includes a vehicle stability control responsive to an indicated vehicle lateral acceleration in a turn to determine, independently of the vehicle body control, a stability compression damping command for the suspension dampers on the side of the vehicle opposite the direction of the lateral acceleration and a stability rebound damping command for the suspension dampers on the side of the vehicle in the direction of the lateral acceleration.

Abstract: A vehicle suspension system is responsive to an active brake signal from a brake system indicating the application of a greater braking force to one front corner brake than to the other front corner brake to affect vehicle yaw rate. The vehicle suspension system determines the relative velocities of the front corner suspension adjacent the front corner brake receiving the greater braking force and the diagonally opposed rear corner suspension and further determines a compression damping command for the front corner suspension and a rebound damping command for the rear corner suspension. While the active brake signal is present, the suspension control applies the compression damping command for the front corner suspension when its relative velocity indicates that it is in compression. While the active brake signal is present, the suspension control also applies the rebound damping command for the rear corner suspension when its relative indicates that it is in rebound.

Abstract: In a vehicle with four corner suspensions, wherein during a transient turning maneuver, a body of the vehicle tends to compress two of the corner suspensions on a first side of the vehicle and expand two of the corner suspensions on a second side of the vehicle, wherein road inputs cause random compression and rebound of the four corner suspensions, a suspension control method comprising the steps of: sensing vehicle speed; monitoring steering wheel velocity; responsive to the vehicle speed and the steering wheel velocity, determining a signal indicative of a transient turning maneuver of the vehicle; responsive to the signal, determining compression damping commands for the two corner suspensions on the first side of the vehicle; responsive to the signal, determining rebound damping commands for the two corner suspensions on the second side of the vehicle; monitoring relative velocity of each corner suspension; applying the compression damping commands for the two corner suspensions on the first side of the