Disclosed herein in an exemplary embodiment is a method for providing variable
assist in an active steering system of a vehicle. The method comprises: receiving
an input signal that includes at least one of, a variable ratio command signal,
a stability command signal, a hand wheel position signal, a vehicle speed signal
indicative of a speed of the vehicle, a signal indicative of an operator selected
function, and a signal indicative a vehicle operating mode. The method also comprises:
generating an assist command to an assist mechanism responsive to the input signal
wherein the assist mechanism is operatively coupled to the differential actuator
and a road wheel of the steering system to provide an assist torque responsive
to the motion of the output shaft. The active steering system includes a hand wheel
operatively coupled to an input of a differential actuator and a motor operatively
coupled to the differential actuator. The differential actuator is configured to
translate motion of the input into motion of the output shaft, where the motion
of the output shaft is further responsive to the motor and wherein the output shaft
is coupled to the road wheel of the steering system.
