driving the motor in {HEAD ~ accordance} with {TAIL ~ the fed input signal} to move the movable member to the desired final position 
driving the motor in { HEAD ~ accordance } with { TAIL ~ the fed input signal } to move the movable member to the desired final position
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH