Patent ID: 8494719

Claim:
An active rear steering control system for a vehicle, comprising: a front steering angle sensor configured to measure a front steering angle of the vehicle; a yaw rate sensor configured to measure a yaw rate of the vehicle; a speed sensor configured to measure a speed of the vehicle; and a controller comprising instructions that, when executed by a processor, cause the processor to at least: calculate a first rear steering angle based on the front steering angle; calculate a second rear steering angle based on the yaw rate; select a marker indicative of a vehicle state, yielding a vehicle state marker, selecting the vehicle state marker including: comparing a steering angle velocity to a steering angle velocity threshold, comparing a yaw acceleration to a yaw acceleration threshold, and comparing vehicle speed to a speed threshold; wherein the steering angle velocity is the rate of change of the steering angle and the yaw acceleration is the rate of change of the yaw rate; select a first shaping function associated with the first rear steering angle based on the vehicle state marker and the first rear steering angle; select a second shaping function associated with the second rear steering angle based on the vehicle state marker and the second rear steering angle; and calculate a rear steering command based on the first rear steering angle, the second rear steering angle, the first shaping function, and the second shaping function.