Narrow-frequency-band feedback control of steering pinion torque in an electric power steering system

A computer implemented method to mitigate external disturbances experienced by an electric power steering (EPS) system within a vehicle via feedback control, comprising:

• receiving a disturbance to a pinion shaft within the EPS system, the disturbance is within a predetermined bandwidth;
• calculating torque applied to the pinion shaft from the external disturbance to create a pinion torque signal;
• filtering the pinion torque signal to the predetermined bandwidth;
• amplifying the filtered pinion torque signal;
• generating a counter torque signal based at least in part upon the pinion torque signal;
• and
• mitigating the external disturbance by applying the counter torque signal to the EPS motor.

A feedback control system to mitigate a disturbance within a bandwidth received by an electric power steering (EPS) system within a vehicle, comprising:

• a torque sensor that calculates a torque value associated with the disturbance applied to the EPS system, the torque sensor outputs a torque signal related to the torque value;
• a filter that filters the torque signal to the bandwidth associated with the external disturbance, the signal output is a filtered torque signal;
• an amplifier that adjusts the gain of the filtered torque signal, the signal output is a filtered, amplified torque signal;
• and
• a logic module that receives the filtered, amplified torque signal, generates a counter torque signal that is an inverse of the filtered, amplified torque signal and outputs the counter torque signal to the EPS system to mitigate the torque received from the external source.