a control unit for setting a target motor current on {HEAD ~ the basis} of at least the steering torque detected by {TAIL ~ said steering torque sensor} 
a control unit for setting a target motor current on { HEAD ~ the basis } of at least the steering torque detected by { TAIL ~ said steering torque sensor }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL